Papers for Tuesday, Aug 30 2022

We present the first intensive study of the variability of the near-infrared coronal lines in an active galactic nucleus (AGN). We use data from a one-year long spectroscopic monitoring campaign with roughly weekly cadence on NGC 5548 to study the variability in both emission line fluxes and profile shapes. We find that in common with many AGN coronal lines, those studied here are both broader than the low-ionisaton forbidden lines and blueshifted relative to them, with a stratification that implies an origin in an outflow interior to the standard narrow line region. We observe for the first time [S VIII] and [Si VI] coronal line profiles that exhibit broad wings in addition to narrow cores, features not seen in either [S IX] or [Si X]. These wings are highly variable, whereas the cores show negligible changes. The differences in both the profile shapes and variability properties of the different line components indicate that there are at least two coronal line regions in AGN. We associate the variable, broad wings with the base of an X-ray heated wind evaporated from the inner edge of the dusty torus. The coronal line cores may be formed at several locations interior to the narrow line region: either along this accelerating, clumpy wind or in the much more compact outflow identified with the obscurer and so emerging on scales similar to the outer accretion disc and broad line region.

We present an analysis on the behaviour of the Galactic bulge and the Large Magellanic Cloud (LMC) $\delta$ Scuti stars in terms of period-colour and amplitude-colour (PCAC) relations at maximum, mean and minimum light. The publicly available Optical Gravitational Lensing Experiment-IV (OGLE-IV) light curves for Galactic bulge and OGLE-III light curves for LMC $\delta$ Scuti stars are exploited for the analysis. It has been found that the Galactic bulge $\delta$ Scuti stars obey flat PC relations at maximum/mean/minimum light while the LMC $\delta$ Scutis have sloped/sloped/flat PC relations at maximum/mean/minimum light. Both the Galactic bulge and the LMC $\delta$ Scutis have sloped/flat/sloped AC relations at maximum/mean/minimum. These relations also show that Galactic $\delta$ Scutis are hotter as compared to their LMC counterparts. The period-amplitude (PA) relations for $\delta$ Scutis exhibit different behaviour in the Galactic bulge and the LMC. The LMC variables are found to have higher amplitudes at a given period. The amplitude of the Galactic bulge $\delta$ Scuti shows a bimodal distribution which can be modelled using a two-component Gaussian Mixture Model: one component with a lower amplitude and another with a higher amplitude. The observed behaviour of the $\delta$ Scuti PCAC relations can be explained using the theory of the interaction of hydrogen ionization front (HIF) and stellar photosphere as well as the PA diagram. We use MESA-RSP to calculate theoretical non-linear hydrodynamical pulsation models for $\delta$ Scuti stars with input metallicities of $Z=0.02$ and $Z=0.008$ appropriate for the Galactic bulge and LMC, respectively. The observed PCAC relations and theoretical calculations support the HIF-photosphere interaction theory.

Context: Radio-loud AGNs are thought to possess various sites of particle acceleration, which gives rise to the observed non-thermal spectra. Stochastic turbulent acceleration (STA) and diffusive shock acceleration (DSA) are commonly cited as potential sources of high-energy particles in weakly magnetized environments. Together, these acceleration processes and various radiative losses determine the emission characteristics of these extra-galactic radio sources. Aims: The purpose of this research is to investigate the dynamical interplay between the STA and DSA in the radio lobes of FR-II radio galaxies, as well as the manner in which these acceleration mechanisms, along with a variety of radiative losses, collectively shape the emission features seen in these extra-galactic sources. Methods: A phenomenologically motivated model of STA is considered and subsequently employed on a magneto-hydrodynamically simulated radio lobe through a novel hybrid Eulerian-Lagrangian framework. Results: STA gives rise to a curved particle spectrum that is morphologically different from the usual shock-accelerated spectrum. As a consequence of this structural difference in the underlying particle energy spectrum, various multi-wavelength features arise in the spectral energy distribution of the radio lobe. Additionally, we observe enhanced diffuse X-ray emission from radio lobes for cases where STA is taken into account in addition to DSA.

Dwarf galaxies are small, dark matter-dominated galaxies, some of which are embedded within the Milky Way. Their lack of baryonic matter (e.g., stars and gas) makes them perfect test beds for probing the properties of dark matter -- understanding the spatial dark matter distribution in these systems can be used to constrain microphysical dark matter interactions that influence the formation and evolution of structures in our Universe. We introduce a new method that leverages simulation-based inference and graph-based machine learning in order to infer the dark matter density profiles of dwarf galaxies from observable kinematics of stars gravitationally bound to these systems. Our approach aims to address some of the limitations of established methods based on dynamical Jeans modeling. We show that this novel method can place stronger constraints on dark matter profiles and, consequently, has the potential to weigh in on some of the ongoing puzzles associated with the small-scale structure of dark matter halos, such as the core-cusp discrepancy.

Early observations with the James Webb Space Telescope (JWST) indicate an over-abundance of bright galaxies at redshifts z > 10 relative to Hubble-calibrated model predictions. More puzzling still is the apparent lack of evolution in the abundance of such objects between z ~ 9 and the highest redshifts yet probed, z ~ 13-17. In this study, we first show that, despite a poor match with JWST LFs, semi-empirical models calibrated to UVLFs and colours at 4 < z < 8 are largely consistent with constraints on the properties of individual JWST galaxies, including their stellar masses, ages, and rest-ultraviolet spectral slopes. We then show that order-of-magnitude scatter in the star formation rate of galaxies (at fixed halo mass) can indeed boost the abundance of bright galaxies, provided that star formation is more efficient than expected in low-mass halos. However, this solution to the abundance problem introduces tension elsewhere: because it relies on the up-scattering of low-mass halos into bright magnitude bins, one expects typical ages, masses, and spectral slopes to be much lower than constraints from galaxies observed thus far. This tension can be alleviated by non-negligible reddening, suggesting that - if the first batch of photometrically-selected candidates are confirmed - star formation and dust production could be more efficient than expected in galaxies at z > 10.

Over the last three decades, photometric galaxy selection using the Lyman-break technique has transformed our understanding of the high-z Universe, providing large samples of galaxies at 3 < z < 8 with relatively small contamination. With the advent of the James Webb Space Telescope, the Lyman-break technique has now been extended to z ~ 17. However, the purity of the resulting samples has not been tested. Here we use a simple model, built on the robust foundation of the dark matter halo mass function, to show that the expected level of contamination rises dramatically at z > 10, especially for luminous galaxies, placing stringent requirements on the selection process. The most luminous sources at z > 12 are likely at least ten thousand times rarer than potential contaminants, so extensive spectroscopic followup campaigns may be required to identify a small number of target sources.

By mapping the molecular fraction of the Galactic Center (GC), we quantitatively address the question of how much molecular and central the CMZ (Central Molecular Zone) is. For this purpose we analyze the CO and HI-line archival data, and determine the column- (surface-) and volume-molecular fractions, $f_{\rm mol}^\Sigma$ and $f_{\rm mol}^\rho$, which are the ratio of column-mass density of H$_2$ projected on the sky to that of total gas (H$_2$ + HI) from the line intensities, and the ratio of volume-mass densities of \Htwo\ to total gas from the brightness temperature, respectively. It is shown that $f_{\rm mol}^\Sigma$ is as high as $ \sim 0.9-0.95$ in the CMZ, and $f_{\rm mol}^\rho$ is $0.93-0.98$ in the GC Arms I and II attaining the highest value of $\sim 0.98$ toward Sgr B2. The expanding molecular ring (EMR, or the parallelogram) has a slightly smaller $f_{\rm mol}^\Sigma$ as $\sim 0.9-0.93$. We define the CMZ as the region with $f_{\rm mol}^\Sigma \ge 0.8-0.9$ between the shoulders of plateau-like distribution of H$_2$ column density from $l=-1^\circ.1$ to $+1^\circ.8$ having Gaussian vertical distribution with a half thickness of $\pm 0^\circ.2$. The CMZ is embedded in the Central HI Zone (CHZ), which is defined as an HI disc between $l\sim -2^\circ$ and $+2^\circ.5$, $b=-0^\circ.5$ and $+0^\circ.5$. Based on the analysis, we discuss the origin of CMZ and interstellar physics such as the volume filling factors of molecular and HI gases inferred from the difference between $ f_{\rm mol}^\Sigma$ and $f_{\rm mol}^\rho$.

Systematic geomorphological mapping and detailed landform analysis using the highest resolution images obtained by the New Horizons spacecraft reveal the presence of a range of differentiable terrains on Charon, the largest moon of Pluto, that were not examined in detail by the early studies. The most important findings of our work include (1) truncation and omission of large craters (diameters > 30-40 km) and their crater rim ridges along the eastern edges of several north-trending, eastward-convex, arcuate ranges in Oz Terra, (2) lobate ridges, lobate knob trains, and lobate aprons resembling glacial moraine landforms on Earth, (3) dendritic channel systems containing hanging valleys, and (4) locally striated surfaces defined by parallel ridges, knob trains, and grooves that are > 40-50 km in length. The above observations and the topographic dichotomy of Charon' s encountered hemisphere can be explained by a landscape-evolution model that involves (i) a giant impact that created the Vulcan Planitia basin and the extensional fault zone along its northern rim, (ii) a transient atmosphere capable of driving N2-ice glacial erosion of the water-ice bedrock and transporting water-ice debris to sedimentary basins, (iii) regional glacial erosion and transport of earlier emplaced impact ejecta deposits from the highlands of Oz Terra into the lowland basin of Vulcan Planitia, (iv) syn-glaciation north-trending thrusting interpreted to have been induced by Charon' s despinning, and (v) the development of a water-ice debris cover layer over subsurface N2 ice below Vulcan Planitia during global deglaciation. The infilling of the Vulcan Planitia could have been accompanied by cryovolcanism. The extensive modification of impact craters means that the crater size-frequency distributions from Charon should serve only as a lower bound when used to test the formation mechanism of Kuiper belt objects.

We report spectropolarimetric observations of the Type Ia supernova (SN) 2021rhu at four epochs: $-$7, +0, +36, and +79 days relative to its $B$-band maximum luminosity. A wavelength-dependent continuum polarization peaking at $3890 \pm 93$ Angstroms and reaching a level of $p_{\rm max}=1.78% \pm 0.02$% was found. The peak of the polarization curve is bluer than is typical in the Milky Way, indicating a larger proportion of small dust grains along the sightline to the SN. After removing the interstellar polarization, we found a pronounced increase of the polarization in the CaII near-infrared triplet, from $\sim$0.3% at day $-$7 to $\sim$2.5% at day +79. No temporal evolution in high-resolution flux spectra across the NaID and CaIIH&K features was seen from days +39 to +74, indicating that the late-time increase in polarization is intrinsic to the SN as opposed to being caused by scattering of SN photons in circumstellar or interstellar matter. We suggest that an explanation for the late-time rise of the CaII near-infrared triplet polarization may be the alignment of calcium atoms in a weak magnetic field through optical excitation/pumping by anisotropic radiation from the SN.

The abundance ratios [Y$/$Mg], [Y$/$Al], [Y$/$Si], [Y$/$Ca], and [Y$/$Ti] have been suggested as chemical clocks for solar-metallicity dwarf stars in the field as well as for giant stars in open clusters. To verify this last hypothesis, we derive these abundances ratios of 50 giant stars belonging to seven open clusters. To calculate the abundances, we analyze FEROS spectra assuming the LTE-hypothesis. We confirm that [Y$/$Mg], [Y$/$Al], [Y$/$Si], [Y$/$Ca], and [Y$/$Ti] work as chemical clocks for field dwarf stars at the local region (d $<$ 1 kpc) whereas for the field giants the [Y$/$Mg], [Y$/$Al] and [Y$/$Si] also present trends with the ages but high scattering. [Y$/$Ca] and [Y$/$Ti] do not present any correlation with ages in the field giants. In Our open clusters, the behaviour is similar, [Y$/$Mg], [Y$/$Al] and [Y$/$Si] present evident trends, whereas [Y$/$Ca] vs. Ages is a flat and [Y$/$Ti] vs. Ages is less steep. We also confirm that the chemical clocks have high scatter at the early ages. In the case of the compiled sample, the chemical clocks are similar to our results but in some situations there are important differences. Several relations between abundance ratios and ages may be obtained when dwarfs and giants are analyzed, confirming the non-universality of the spectroscopic age indicators.

In this work, the support vector machine (SVM) method is adopted to separate BL Lacertae objects (BL Lacs) and flat spectrum radio quasars (FSRQs) in the plots of photon spectrum index against the photon flux, $\alpha_{\rm ph} \sim {\rm log}\,F$, that of photon spectrum index against the variability index, $\alpha_{\rm ph} \sim {\rm log}\, \textit{V\!I}$, and that of variability index against the photon flux, ${\rm log}\,{V\!I} \sim {\rm log}\,F$. Then we used the dividing lines to tell BL Lacs from FSRQs in the blazars candidates of uncertain types from \textit{Fermi}/LAT catalogue. Our main conclusions are: 1. We separate BL Lacs and FSRQs by $\alpha_{\rm ph} = -0.123\,{\rm log}\,F + 1.170$ in the $\alpha_{\rm ph} \sim {\rm log}\,F$ plot, $\alpha_{\rm ph} = -0.161\,{\rm log}\,{V\!I} + 2.594$ in the $\alpha_{\rm ph} \sim {\rm log}\,{V\!I}$ plot, and ${\rm log}\,{V\!I} = 0.792\,{\rm log}\,F + 9.203$ in the ${\rm log}\,{V\!I} \sim {\rm log}\,F$ plot. 2. We obtained 932 BL Lac candidates and possible BL Lac candidates, and 585 FSRQ candidates and possible FSRQ candidates. 3. Some discussions are given for comparisons with those in literature.

Context. Observations indicate that the fraction of potential binary star clusters in the Milky Way is either the same or lower than that of the Magellanic Clouds. The unprecedented precision in the parallax measurements by Gaia has allowed for the discovery of a growing number of new binary open clusters (OCs). Aims. We aim to survey the candidates of truly binary open clusters that are formed simultaneously, using information from the Gaia database. Methods. Based on the most recent catalog of open clusters, we investigated the interactions of adjacent binary open clusters in our Galaxy within separations of 50 pc. We compared their coordinates, proper motions, parallaxes, and color-magnitude diagrams(CMDs) via binary plots for all candidate pairs. The candidates of truly binary open clusters are selected on the basis of their common proper motions and consistent behaviors in the CMDs of different clusters that are limited to a separation of 50 pc. Results. About ten pairs of the selected binary open clusters appear to be the same clusters, based on evidence that almost half ofthe cluster members are shared. Fourteen pairs are possibly true binaries, implying that they may come from the same clouds, among which five pairs are newly discovered. In addition, two clusters, UBC 46 and UBC 192, were found to be part of the stellar complex LISCA I. Our results confirm that OCs born in groups are usually composed of young open clusters.

General structural properties and low surface brightness tidal features hold important clues to the formation of galaxies. In this paper, we study a sample of polar-ring galaxies (PRGs) based on optical imaging from the Sloan Digital Sky Survey (SDSS) Stripe82 and other deep surveys. We investigate the deepest images of candidates for PRGs to date. We carry out photometric decomposition on the host galaxies and associated polar structures that allows us to derive the structural properties of both components. We are able to detect very faint tidal structures around most PRGs in our sample. For several galaxies, we can directly observe the formation of the polar ring due to merging, which is manifested in debris of the victim galaxy and an arc-like polar structure made up of its material. In a few cases, we can discern signs of tidal accretion. The results obtained indicate that the gravitational interaction and merging of galaxies are the most plausible mechanisms for the formation of polar-ring galaxies.

The damping effect of the free-streaming neutrinos on the second order gravitational waves is investigated in detail. We solve the Boltzmann equation and give the anisotropic stress induced by neutrinos to second order. The first order tensor and its coupling with scalar perturbations induced gravitational waves are considered. We give the analytic equations of the damping kernel functions and finally obtain the energy density spectrum. The results show that the free-streaming neutrinos suppress the density spectrum significantly for low frequency gravitational waves and enlarge the logarithmic slope $n$ in the infrared region ($k \ll k_*$) of the spectrum. For the spectrum of $k_*\sim 10^{-7}$Hz, the damping effect in the range of $k<k_*$ is significant. The combined effect of the first and second order could reduce the amplitude by $30\%$ and make $n$ jump from $1.54$ to $1.63$ at $k\sim 10^{-9}$Hz, which may be probed by the pulsar timing arrays (PTA) in the future.

We present MeerKAT HI observations of six jellyfish candidate galaxies (JFCGs) in the galaxy cluster, A2626. Two of the six galaxies JW100 and JW103, that were identified as JFCGs from B-band images, are confirmed as jellyfish galaxies (JFGs). Both of the JFGs have low HI content, reside in the cluster core, and move at very high velocities ($\sim$ 3$\sigma_{cl}$). The other JFCGs, identified as non-jellyfish galaxies, are HI rich, with HI morphologies revealing warps, asymmetries, and possible tidal interactions. Both the A2626 JFGs and three other confirmed JFGs from the GASP sample show that these galaxies are HI stripped but not yet quenched. We detect HI, Halpha, and CO tails of similar extent ($\sim$ 50 kpc) in JW100. Comparing the multi-phase velocity channels, we do not detect any HI or CO emission in the northern section of the tail where Halpha emission is present, possibly due to prolonged interaction between the stripped gas and the ICM. We also observe an anti-correlation between HI and CO, which hints at an efficient conversion of HI to H2 in the southern part of the tail. We find that both RPS and HI-to-H2 conversion are significant depletion channels for atomic gas. HI-to-H2 conversion is more efficient in the disc than in the tail.

Optical interferometry is a powerful technique to achieve high angular resolution. However, its main issue is its lack of sensitivity, compared to other observation techniques. Efforts have been made in the previous decade to improve the sensitivity of optical interferometry, with instruments such as PIONIER and GRAVITY at VLTI, or MIRC-X and MYSTIC at CHARA. While those instruments pushed on sensitivity, their design focus was not the sensitivity but relative astrometric accuracy, imaging capability, or spectral resolution. Our goal is to build an instrument specifically designed to optimize for sensitivity. This meant focusing our design efforts on different parts of the instrument and investigating new technologies and techniques. First, we make use of the low-noise C-RED One camera using e-APD technology and provided by First Light Imaging, already used in the improvement of sensitivity in recent new instruments. We forego the use of single-mode fibers but still favor an image plane design that offers more sensitivity than a pupil plane layout. We also use a minimum number of optical elements to maximize the throughput of the design, using a long focal length cylindrical mirror. We chose to limit our design to 3 beams, to have the capability to obtain closure phases, but not dilute the incoming flux in more beam combinations. We also use in our design an edge filter to have the capability to observe H- and K-band at the same time. We use a low spectral resolution, allowing for group delay fringe tracking but maximizing the SNR of the fringes for each spectral channel. All these elements will lead to a typical limiting magnitude between 10 and 11 in both H- and K-bands.

This work presents timing and spectral analysis of 4U 2206+54 using data obtained from LAXPC instrument onboard India's AstroSat mission. This source was observed with AstroSat in September 2016 and October 2016. We report detection of $5648 (4)$ s pulsations at MJD 57669 in the latter observation of 4U 2206+54. The pulse profile is sinusoidal and the inherent shape is independent of energy up to 30 keV. The pulse fraction increases with energy from $\sim 0.5$% to $\sim 0.8$%. We report an updated spin down rate of $2.95 (14) \times 10^{-7}$ s s$^{-1}$. This is about 0.40 times smaller than the previously reported long term value. The energy spectrum is best modelled with an absorbed power-law with high energy exponential cut-off. We have detected presence of broad emission line in 4U 2206+54 at an energy of $7$ keV with equivalent width of $\sim 0.4$ keV.

Using the Gaia DR2 and EDR3 data and list of post-AGB candidates, we investigate the parallax, proper motion and binarity for twenty post-AGB stars and candidates having high radial velocities. From their Gaia distances their luminosities and kinematics are derived. The evolutionary status of these stars is discussed from their location on the post-AGB evolutionary tracks. Nine stars are confirmed to be post-AGB stars that have their initial main-sequence mass around one or two solar masses. From their kinematics information, two objects among them are identified to clearly belong to the halo population, suggesting that low-mass. We discuss on the origin and evolutionary status of other objects in the sample of this work with high radial velocities.

The Hubble tension can be addressed by modifying the sound horizon ($r_s$) before recombination, triggering interest in $r_s$-free early-universe estimates of the Hubble constant, $H_0$. Constraints on $H_0$ from an $r_s$-free analysis of the full shape BOSS galaxy power spectra within LCDM were recently reported and used to comment on the viability of physics beyond LCDM. Here we demonstrate that $r_s$-free analyses with current data depend on the model and the priors placed on the cosmological parameters, such that LCDM analyses cannot be used as evidence for or against new physics. We find that beyond-LCDM models which introduce additional energy density with significant pressure support, such as early dark energy (EDE) or additional neutrino energy density ($\Delta N_{\rm eff}$), lead to larger values of $H_0$. On the other hand, models which only affect the time of recombination, such as a varying electron mass ($\Delta m_e$), produce $H_0$ constraints similar to LCDM. Using BOSS data, constraints from light element abundances, cosmic microwave background (CMB) lensing, a CMB-based prior on the scalar amplitude ($A_s$), spectral index ($n_s$), and $\Omega_m$ from the Pantheon+ supernovae data set, we find that in LCDM, $H_0=64.9\pm 2.2$ km/s/Mpc; EDE, $H_0=68.7^{+3}_{-3.9}$; $\Delta N_{\rm eff}$, $H_0=68.1^{+2.7}_{-3.8}$; $\Delta m_e$, $H_0=64.7^{+1.9}_{-2.3}$. Using a prior on $\Omega_m$ from uncalibrated BAO and CMB measurements of the projected sound horizon, these values become in LCDM, $H_0=68.8^{+1.8}_{-2.1}$; EDE, $H_0=73.7^{+3.2}_{-3.9}$; $\Delta N_{\rm eff}$, $H_0=72.6^{+2.8}_{-3.7}$; $\Delta m_e$, $H_0=68.8\pm 1.9$. With current data, none of the models are in significant tension with SH0ES, and consistency tests based on comparing $H_0$ posteriors with and without $r_s$ marginalization are inconclusive with respect to the viability of beyond LCDM models.

Transmission spectroscopy is among the most fruitful techniques to infer the main opacity sources present in the upper atmosphere of a transiting planet and to constrain the composition of the thermosphere and of the unbound exosphere. Not having a public tool able to automatically extract a high-resolution transmission spectrum creates a problem of reproducibility for scientific results. As a consequence, it is very difficult to compare the results obtained by different research groups and to carry out a homogeneous characterization of the exoplanetary atmospheres. In this work, we present a standard, publicly available, user-friendly tool, named SLOPpy (Spectral Lines Of Planets with python), to automatically extract and analyze the optical transmission spectrum of exoplanets as accurately as possible. Several data reduction steps are first performed by SLOPpy to correct the input spectra for sky emission, atmospheric dispersion, the presence of telluric features and interstellar lines, center-to-limb variation, and Rossiter-McLaughlin effect, thus making it a state-of-the-art tool. The pipeline has successfully been applied to HARPS and HARPS-N data of ideal targets for atmospheric characterization. To first assess the code's performance and to validate its suitability, here we present a comparison with the results obtained from the previous analyses of other works on HD 189733 b, WASP-76 b, WASP-127 b, and KELT-20 b. Comparing our results with other works that have analyzed the same datasets, we conclude that this tool gives results in agreement with the published results within 1$\sigma$ most of the time, while extracting, with SLOPpy, the planetary signal with a similar or higher statistical significance.

A number of new $z>11$ galaxy candidates have been identified based on public James Webb Space Telescope (JWST) NIRCam observations. Spectroscopic confirmation of these candidates is necessary to robustly measure their redshift and put them in the context of our understanding of the buildup of galaxies in the early Universe. GLASS-z13 is one of these candidates, with a reported photometric redshift $z>11.9$, a stellar mass of $\log{(M_{\rm star}/\rm{M}_\odot)} = 9.0^{+0.3}_{-0.4}$ and star-formation rate (SFR) averaged over the last 50 Myr of $7^{+4}_{-3}\,\rm{M}_\odot\,\rm{yr}^{-1}$. I present publicly available ALMA band 6 DDT observations (project 2021.A.00020.S; PI T. Bakx), taken to acquire a spectroscopic redshift for GLASS-z13 by searching for [\ion{O}{III}]\,88\,\textmu m line emission in the redshift range $z=11.9-13.5$. No [\ion{O}{III}]\,88\,\textmu m emission is detected in integrated spectra extracted within an aperture around GLASS-z13, nor when using an automated line finding algorithm (applying different uv-weighting strategies for the imaging). 1.2~mm continuum emission associated to GLASS-z13 is not detected either. If GLASS-z13 is at z$\approx$12-13, this implies a 3-$\sigma$ upper limit on the [\ion{O}{III}]\,88\,\textmu m and rest-frame $\sim$90 $\mu$m continuum emission of $\sim6\times10^6\,\rm{L}_\odot$ and 10.8 $\mu$Jy, respectively. The non-detection of [\ion{O}{III}]\,88\,\textmu m and continuum emission does not necessarily imply that GLASS-z13 is not at $z\approx12-13$. It can also be explained by low metallicity interstellar medium ($\sim 0.05\,\rm{Z}_\odot$ or lower), in agreement with predictions by recent simulations for $z\sim 12$ galaxies. This demonstrates the synergy between ALMA and JWST to study the properties of the first galaxies, although JWST/NIRSpec spectroscopy will be necessary to confirm or reject the high photometric-redshift of GLASS-z13.

In [arXiv:2208.09842], Yuennan and Channuie examined four inflation models, such as Composite NJL Inflation(NJLI), Glueball Inflation(GI), super Yang-Mills Inflation (SYMI), and Orientifold Inflation (OI) from further refining the dS swampland conjecture (FRSDC) perspective. They found that all models violate the dS swampland conjecture(DSC) but are compatible with (FRSDC) through manual adjustment of free parameters of the mentioned conjecture. Now, in this article, we want to check each of the mentioned inflation models with two other conjectures of the swampland program: scalar weak gravity conjecture (SWGC) and strong scalar weak gravity conjecture (SSWGC). We want to study the simultaneous compatibility of each model with these two new conjectures. Despite being consistent with (FRSDC), we find that all models are not compatible with the other conjectures of the Swampland program in all regions, and these conjectures are only satisfied in a specific area. Also, Due to the presence of constant parameter ($\phi_{0}$) in the higher orders derivatives, the (SYMI) and (OI) among all the models are more compatible with all conjectures of the swampland program. They can provide a more significant amount of satisfaction with all of them. They can be suitable and accurate inflation models for a more profound examination of universe developments. We determined a particular region for these models is compatible with (FRSDC), (SWGC), and (SSWGC) simultaneously.

We develop a Monte Carlo radiative transfer code to study the effect of turbulence with a finite correlation length on scattering of Lyman-alpha (Ly$\alpha$) photons propagating through neutral atomic hydrogen gas. We investigate how the effective mean free path, the emergent spectrum, and the average number of scatterings that Ly$\alpha$ photons experience change in the presence of turbulence. We find that the correlation length is an important and sensitive parameter, which can significantly, by orders of magnitude, reduce the number of scattering events that the average Ly$\alpha$ photon undergoes before it escapes the turbulent cloud. This can have consequences for the effectiveness of the Wouthuysen-Field coupling of the spin temperature to Ly$\alpha$ radiation as well as affect the polarization of the scattered photons.

The Sun represents a promising target for indirect dark matter searches, as dark matter particles from the Galactic halo can be gravitationally trapped in its core or in external orbits, and their annihilations can lead to final states with standard model particles that are able to reach the Earth. In this work we have considered a scenario in which dark matter particles can annihilate into pairs of long-lived mediators, which in turn can escape from the Sun and decay into pairs of gamma rays or into the $b\bar{b}$, $\tau^{+}\tau^{-}$, $\mu^{+}\mu^{-}$ channels, with the production of gamma rays in the final states. All these processes are expected to yield an excess in the energy spectrum of gamma rays towards the Sun. We have therefore analyzed the data collected by the Fermi Large Area Telescope during its first 13.5 years of operation, searching for possible excesses in the solar gamma-ray spectrum. Since no statistically significant excess is found, we have set constraints on the dark matter-nucleon scattering cross sections in both the spin-dependent and spin-independent cases. For all the mediator decay channels explored and for dark matter masses between a few GeV/c${^2}$ and 1 TeV/c${^2}$, we have found that the upper limits on the spin-dependent and spin-independent cross sections are in the ranges from $10^{-45}$ to $10^{-39}$ cm$^{2}$ and from $10^{-47}$ up to $10^{-42}$ cm$^{2}$, respectively.

Recent observations with JWST have identified several bright galaxy candidates at $z\gtrsim 10$, some of which appear unusually massive (up to $\sim 10^{11}\ \rm M_{\odot}$). Such early formation of massive galaxies is difficult to reconcile with standard $\Lambda\rm CDM$ predictions, demanding very high star formation efficiency (SFE), possibly even in excess of the cosmic baryon mass budget in collapsed structures. With an idealized analysis based on linear perturbation theory and the Press-Schechter formalism, we show that the observed massive galaxy candidates can be explained with lower SFE than required in $\Lambda\rm CDM$, if structure formation is accelerated by massive ($\gtrsim 10^{9}\ \rm M_{\odot}$) primordial black holes (PBHs) that enhance primordial density fluctuations. We identify the region of PBH parameter space, allowed by existing empirical constraints, that can produce the most massive galaxy candidates observed by JWST, and discuss the general signatures of PBH cosmologies in the JWST era.

A well-known active galaxy of the blazar type, S5 0716+714, is characterised by a particularly high variability duty cycle on short-time scales at optical frequencies. As such, the source was subjected to numerous monitoring programs, including both ground-based as well as space-borne telescopes. On closer inspection of the most recent accumulation of the data provided by the Transiting Exoplanet Survey Satellite, we have noticed several conspicuous events with `volcano-like' symmetric shape, lasting all for several hours, which closely resemble the achromatic events detected with the previous Whole Earth Blazar Telescope campaigns targeting the source. We propose that those peculiar features could be due to the gravitational micro-lensing of the innermost segments of the precessing jet in the system, by a binary lens. We study the magnification pattern of the lens with the inverse-ray shooting method, and the source trajectory parameters with the Python package MuLensModel. In this way, we were able to fit successfully all the selected events with a single lens, adjusting slightly only the source trajectory parameters for each lensing event. The main implication of the analysis is the presence of a massive binary lens, containing an intermediate-mass black hole, possibly even a super-massive one, and a much less massive companion (by a factor of $\lesssim 0.01$), located within the host galaxy of the blazar, most likely the central kiloparsec region. We discuss the major physical implications of the proposed scenario regarding the quest for the intermediate-mass and dual supermassive black holes in active galaxies.

Modern understanding of dust astrophysics reveals that RAdiative Torques (RATs) arising from the radiation-dust interaction can induce two fundamental effects, including grain alignment and rotational disruption. Here we review the recent progress in the theoretical development and observational testing of these effects using dust polarization observed toward star-forming regions (SFRs). We first review the basic theory of the RAT alignment and RAT disruption, which are referred to as RAT-A and RAT-D effects, respectively. We then briefly describe the numerical method we use to model polarized thermal dust emission by accounting for both RAT-A and RAT-D and theoretical predictions of dust polarization for observations. Next, we review our observational efforts to search for observational evidence of the RAT-A and RAT-D effects using thermal dust polarization toward SFRs. Finally, we discuss magnetic fields inferred from dust polarization observed toward these SFRs and implications of the RAT paradigm for different astrophysical conditions, including protostellar environments, dust evolution, and time-domain astrophysics.

The Galactic centre (GC) is located at only 8 kpc from Earth and constitutes a unique template to understand Galactic nuclei. Nevertheless, the high crowding and extinction towards the GC hamper the study of its main stellar components, the nuclear stellar disc (NSD) and the nuclear star cluster (NSC). Recent work has suggested that the NSD and the NSC can be distinguished along the line of sight towards the NSC via the different extinction of their stars. This motivated us to analyse the proper motion, radial velocity, and the metallicity distributions of the different extinction groups. We use photometric, kinematic, and metallicity data to distinguish between probable NSD and NSC stars in a region centred on the NSC. We detected two different extinction groups of stars and obtained significantly different proper motion distributions for each of them, in agreement with the expected kinematics for the NSD and the NSC. We derived radial velocity maps that appear to be different for the NSD and the NSC. We also found different metallicities for each of the components, with the largest one measured for the most extinguished group of stars. We obtained that the metallicity distribution of each extinction group is best fitted by a bimodal distribution, indicating the presence of two metallicity components for each of them (a broad one slightly below solar metallicity, and a more metal rich narrower one, that is largest for the high extinction group of stars). We conclude that both extinction groups are distinct GC components with different kinematics and metallicity, and correspond to the NSD and the NSC. Therefore, it is possible to distinguish them via their different extinction. The high mean metallicity, $[M/H]\sim0.3$\,dex, obtained for the NSC metal rich stars, supports that the NSC is arguabily the most metal rich region of the Galaxy.

We calculate the lightcurves of jet-driven bipolar core collapse supernova (CCSN) explosions into a bipolar circumstellar mater (CSM) and show that an equatorial observer finds the lightcurves to possess a rapid, and even an abrupt, drop. The scenario that might lead to such an explosion morphology is a common envelope evolution (CEE) where shortly before the CCSN explosion the RSG progenitor interacts with a more compact companion that spirals-in and spins-up the core. The companion can be a main sequence star, a neutron star, or a black hole. The binary interaction ejects a shell through an intensive wind and the CEE ejects a denser gas in the equatorial plane. We assume that the companion accretes mass and launches jets. We conduct three-dimensional (3D) hydrodynamical simulations where we launch weak jets, the shaping jets, into the dense shell and show that the interaction forms a bipolar CSM. As a result of the rapid pre-collapse core rotation jets drive the CCSN explosion. We simulate the interaction of the jets with the bipolar CSM and use a simple scheme to calculate the lightcurves. We show that the abrupt drop in the lightcurve of an observer not too close to the polar directions can account for the lightcurve of the hydrogen poor luminous supernova (LSN) SN 2018don. Our study strengthens the claim that jet-driven explosions account for many, even most, CCSNe.

The Heliophysics Decadal survey should embrace the coming opportunity of sustained lunar surface exploration and facilitate cross-disciplinary efforts to unlock the secrets of the Sun that are held by the lunar surface. With planned Artemis efforts that include prioritization of samples of high interest and protocols for sample handling and analysis, input into the relevant solar signatures that would be most diagnostic and how best to obtain/retain them is incredibly important. Finally, leveraging the theoretical expertise of the two communities in ways that bring them together, such as through dedicated conferences and workshops, will let the two communities help each other learn more than they could alone.

We report results on the timing analysis of the 2020 giant outburst of 1A 0535+262, using broadband data from Insight-HXMT. The analysis of the pulse profile evolution from the sub-critical luminosity to super-critical luminosity regime is presented for the first time. We found that the observed pulse profile exhibits a complex dependence on both energy and luminosity.A dip structure at the energy of the cyclotron resonant scattering features (CRSFs) is found for the first time in the pulse fraction-energy relation of 1A 0535+262, when the outburst evolves in a luminosity range from 4.8 $\times 10^{37}$ erg s$^{-1}$ to 1.0 $\times 10^{38}$ erg s$^{-1}$. The observed structure is luminosity dependent and appears around the source critical luminosity ($\sim$ 6.7 $\times 10^{37}$ erg s$^{-1}$).

We present a python based parameter inference system for the gravitational wave (GW) measured in the millihertz band. This system includes the following features: the GW waveform originated from the massive black hole binaries (MBHB), the stationary instrumental gaussian noise, the higher-order harmonic modes, the full response function from the time delay interferometry (TDI) and the gaussian likelihood function with the dynamic nested parameter sampler. In particular, we highlight the role of higher-order modes. By including these modes, the luminosity distance estimation precision can be improved roughly by a factor of 50, compared with the case with only the leading order ($\ell=2,|m|=2$) mode. This is due to the response function of different harmonic modes on the inclination angle are different. Hence, it can help to break the distance-inclination degeneracy. Furthermore, we show the robustness of testing general relativity (GR) by using the higher-order harmonics. Our results show that the GW from MBHB can simultaneously constrain four of the higher harmonic amplitudes (deviation from GR) with a precision of $c_{21}=0.54^{+0.61}_{-0.82}$, $c_{32}=-0.65^{+0.22}_{-0.08}$, $c_{33}=0.56^{+0.60}_{-0.76}$ and $c_{44}=1.57^{+2.34}_{-1.90}$, respectively.

We study the global solutions of slowly rotating accretion flows around the supermassive black hole in the nucleus of an elliptical galaxy. The velocity of accreted gas surrounding the black hole is initially subsonic and then falls onto the black hole supersonically, so accretion flow must be transonic. We numerically solve equations from the Bondi radius to near the black hole. The focus of our discussion will be on the properties of slightly rotating accretion flows in which radiative losses have been ignored. This study discusses how outer boundary conditions (the temperature and specific angular momentum at the outer boundary) influence accretion flow dynamics. We investigate two physically discontinuous regimes: The Bondi-like type accretion and the Disk-like type accretion. A Bondi-like accretion occurs when the specific angular momentum at the Bondi radius $ \ell_{B} $ is smaller than the specific angular momentum at the marginally stable orbit $ \ell_{ms} $. In comparison, a Disk-like accretion occurs when the specific angular momentum at the Bondi radius $ \ell_{B} $ is larger than the specific angular momentum of the marginally stable orbit $ \ell_{ms} $. We also keep the assumption of hydrostatic equilibrium and compare our results with the case in which it is not considered. According to this study, considering the assumption of hydrostatic equilibrium reduces the mass accretion rate. Additionally, we find our solution for different ranges of the viscosity parameter $\alpha$. Finally, we study the effect of galaxy potential on slowly rotating accretion flows.

We find 132 face-on and low inclination galaxies with central star formation driven biconical gas outflows (FSFB) in the SDSS MaNGA (Mapping Nearby Galaxies at APO) survey. The FSFB galaxies show either double peaked or broadened emission line profiles at their centres. The peak and maximum outflow velocities are 58 and 212 km/s, respectively. The gas velocity dispersion reveals a mild dependence on the central star formation surface density compatible with models of gas dispersion powered by the Jeans instability in gas clumps or by gas turbulence dissipation. We estimate the gas outflow rate and conclude that the central gas depletion time does not depend on galactic mass. In turn, the ratio of the gas outflow rate to the gas consumption rate by the star formation is low in massive galaxies and high in low-mass objects, while the star formation is a more rapid process of the gas consumption. We compare properties of the FSFB galaxies with a control sample of 375 comparison galaxies and find that the FSFB objects have high central concentration of star formation, and also younger central stellar population with respect to their periphery. We analysed the environment of the galaxies and identified nearby satellites and elements of low surface brightness structure. We see that many tidal-enhanced features that can be assigned to early and intermediate stages of galactic interaction are much more frequent in the FSFB galaxies with respect to the comparison sample. We conclude that the gas should be replenished via the accretion from small satellites.

We have carried out a multiple regression analysis of the 21cm HI emission combined with the sub-mm dust emission over 80 per cent of the sky at a resolution of 47arcmin. The method covers the sky contiguously, and is distinguished from the optical absorption line measurements toward bright stars which cover a tiny fraction of the gas. On the assumption that the dust-to-gas ratio is proportional to the metallicity, we derived the metallicity of all the HI components, i.e., the intermediate velocity clouds (IVCs), the high velocity clouds (HVCs), as well as the local HI gas. Major results include that the metallicity of the IVCs is in a range of 0.1 -- 1.5 (relative to the majority of local diffuse HI gas) with a mode at 0.6, and that a significant fraction, $\sim$30 per cent, of the IVCs includes the low metallicity gas of <0.3. In addition, it is revealed that 80 per cent of the HVC Complex C has a metallicity of <0.3, and that the Magellanic Stream has a uniform very low metallicity of <0.1. We argue that a large fraction of the low metallicity IVC gas may favor a picture of the external low-metallicity HI gas accretion instead of the Galactic-fountain model. In addition, we find that the IVCs show a trend that metallicity of the IVCs increases with velocity decrease, suggesting that the IVCs are accumulating high metallicity halo gas via dynamical interaction at z<1 kpc.

The Jovian system is a treasure trove of X-ray sources: diverse and dynamic atmospheric and auroral emissions, diffuse radiation belt and Io torus emissions, and plasma-surface interactions with Jupiter's moons. The system is a rich natural laboratory for astronomical X-rays with each region showcasing its own X-ray production processes: scattering and fluorescence of solar corona emissions; charge exchange emissions from energetic ions; Inverse-Compton, thermal and non-thermal bremsstrahlung emissions from relativistic electrons; and fingerprint fluorescence lines indicative of elemental composition and the potential for life on the Galilean satellites. For the high energy astrophysics domain, perhaps Jupiter's greatest attribute is the opportunity to connect observed X-ray emissions with in-situ plasma and magnetic field measurements of the precise physical processes that lead to them - irreplaceable ground truths for systems that cannot be visited in-situ. Such simultaneous studies have revealed that Jupiter's spectacular soft X-ray flares and pulsations are produced by wave-particle interactions, while the bremsstrahlung aurorae vary with magnetodisk reconnection and dipolarisation. While many remote signatures remain to be linked with their source processes, the future is bright, with synergistic Chandra, NuSTAR, XMM-Newton and Juno in-situ measurements continuing to provide revolutionary insights in the coming years, while JUICE and Europa missions with ATHENA and possibly Lynx will enable a new legacy. However, to truly characterise some emissions (e.g. mapping Galilean satellite elemental composition) in-situ X-ray instrumentation is a necessity. Recent advances enable compact, lightweight, X-ray instrumentation perfectly suited for Jupiter science. The chapter closes by reviewing feasible, low-risk concepts that would paradigm-shift our understanding of the system.

Accurate numerical-relativity simulations are essential to study the rich phenomenology of binary neutron star systems. In this work, we focus on the material that is dynamically ejected during the merger process and on the kilonova transient it produces. Typically, radiative transfer simulations of kilonova light curves from ejecta make the assumption of homologous expansion, but this condition might not always be met at the end of usually very short numerical-relativity simulations. In this article, we adjust the infrastructure of the BAM code to enable longer simulations of the dynamical ejecta with the aim of investigating when the condition of homologous expansion is satisfied. In fact, we observe that the deviations from a perfect homologous expansion are about 30% at roughly 100ms after the merger. To determine how these deviations might affect the calculation of kilonova light curves, we extract the ejecta data for different reference times and use them as input for radiative transfer simulations. Our results show that the light curves for extraction times later than 80ms after the merger deviate by less than 0.4mag and are mostly consistent with numerical noise. Accordingly, deviations from the homologous expansion for the dynamical ejecta component are negligible for the purpose of kilonova modelling.

Field of View (FoV) and contrast limitations of stellar interferometers have been the scope of numerous publications for more than thirty years. Recently, this topic regained some interest since long-baseline terrestrial interferometers or space borne nulling interferometers are envisioned for detecting and characterizing extra-solar planets orbiting in the habitable zone of their parent star. This goal supposes to achieving sufficient contrast ratio in the high angular frequency domain, thus on the whole interferometer FoV. In this paper are reviewed some of the contrast and FoV limiting factors, including spectral bandwidth, flux mismatches, fringe tracking, telescope image quality, atmosphere seeing, optical conjugation mismatch of the telescopes pupils, influence of anamorphous optics, pupil aberrations, signal-to-noise ratio and deviations with respect to the golden rule of imaging interferometers. Finally, a tentative classification of all these factors is provided.

Space borne nulling interferometry in the mid-infrared waveband is one of the most promising techniques for characterizing the atmospheres of extra-solar planets orbiting in the habitable zone of their parent star, and possibly discovering life markers. One of its most difficult challenges is the control of free-flying telescope spacecrafts moving around a central combiner in order to modulating the planet signal, within accuracy better than one micrometer at least. Moreover, the whole array must be reconfigured regularly in order to observe different celestial targets, thus increasing the risk of loosing one or more spacecrafts and aborting the mission before its normal end. In this paper is described a simplified optical configuration where the telescopes do not need to be rotated, and the number of necessary array reconfigurations is minimized. It allows efficient modulation of the planet signal, only making use of rotating prisms or mirrors located into the central combiner. In this paper the general principle of a nulling interferometer with a fixed telescope array is explained. Mathematical relations are established in order to determining the planet modulation signal. Numerical simulations are carried out for three different arrangements of the collecting telescopes. They confirm that nulling interferometry in space does not require a rotating telescope array

Coronagraphy is an efficient technique for identifying and characterizing extra-solar planets orbiting in the habitable zone of their parent star. An important family of coronagraphs is based on amplitude or phase filters placed at an intermediate image plane of the optical system, spreading starlight outside of the so-called Lyot stop located at the exit pupil plane of the instrument. This article explores the potential of circular amplitude and phase gratings employed as image plane coronagraph filters. It presents a theoretical analysis of the simplest case of an amplitude circular grating and introduces an inversion paradigm with respect to classical Lyot coronagraph, by exchanging its image and pupil masks. Various types of circular gratings are considered and their performance is evaluated with the help of numerical simulations. The most promising solutions are presented. We conclude that high attenuation ratios of the starlight are feasible, provided that the system has been carefully optimized

We present an analysis of high latitude $\delta$ Scuti stars ($\left|b\right|> 1^{\circ}$) in the Galactic bulge region ($-8^{\circ}.3< l<9^{\circ}.4$) using a clean sample of the photometric data of $7,440$ stars recently released by the OGLE-IV project. The geometrical parameters of the bulge are determined based on Maximum Likelihood (ML) analysis in five-dimensional parameter space. More refined values of these parameters as well as their uncertainties are obtained from a fully Bayesian Markov Chain Monte Carlo (MCMC) analysis. Approximating the bulge as an ellipsoid, the distribution of the number density of stars as a function of Galacto-centric distance has been modelled using three distribution functions: two Exponential ($\rm E_{1},\rm E_{2}$) types and one Gaussian ($\rm G$) type. Based on the AIC and BIC values, the exponential model $\rm E_{1}$ is chosen as the best statistical model for the parameter values obtained from the MCMC analysis. The MCMC analysis yields the following results: the mean distance to the Galactic center (GC) is found to be $R_{0}=8.034\pm0.012_{\rm stat}\pm0.586_{\rm sys}$ kpc; the bulge $\delta$ Scuti distribution has a triaxial shape with normalized ($a\equiv1$) axes ratios ($a:b:c$) as $1.000\pm 0.005:0.348\pm0.002:0.421\pm0.002$. Here $a$ is the semi-major axis lying in the Galactic plane and pointing towards us; $b$ and $c$ are the two semi-minor axes, the former lying in the Galactic plane and the later perpendicular to it. Smaller values of $b$ as compared to $a$ obtained for Galacto-centric distances $R\ge 2.0$~kpc indicate the presence of a bar-like structure of the bulge with a bar angle of $22^{\circ}.006\pm2^{\circ}.078$.

This is a brief review on some properties of galaxies in the fuzzy dark matter model, where dark matter is an ultra-light scalar particle with mass $m = O(10^{-22})eV$. From quantum pressure, dark matter has a halo length scale which can solve the small scale issues of the cold dark matter model, such as the core-cusp problem, and explain many other observed mysteries of galaxies.

The paper describes profile broadening and peak wavelength variation of diffuse interstellar bands (DIBs) measured for 46 lines of sight, probably caused by physical properties of intervening clouds. Full width at half maximum of four studied diffuse bands (5780, 5797, 6196 and 6614 \AA) demonstrate strong variability sometimes doubling the features' width. Despite the high magnitude of the effect, our current analysis is restricted to the strongest diffuse bands because the weaker ones require a much higher S/N ratio. The profile broadening in the studied DIBs moves the profile's centers towards longer wavelengths, probably due to the excitation of higher levels of the P branch of the unknown molecular carrier. Moreover, diffuse bands are broader in clouds with abundantly populated vibrationally excited states of the hydrogen molecules, i.e. DIB's broadening correlates with the rotational temperature estimated on H$_2$ $\nu$=2 vibrational level. However, objects demonstrating extremely broadened profiles of DIBs are scarce. The extreme peculiarity of DIBs' profiles was detected in Herschel~36. Here we show the gradual growths of the widths of diffuse bands, confirmed in spectra from different instruments.

Thin and thick disks are found in most spiral galaxies, yet their formation scenarios remain uncertain. Whether thick disks form through slow or fast, internal or environmental, processes is unclear. The physical origin of outer truncations in thin and thick disks, observed as a drop in optical and near-infrared (NIR) surface brightness profiles, is also a much debated topic. These truncations have been linked to star formation (SF) thresholds in Milky-Way type galaxies, but no such connection has been made for their low-mass counterparts or in thick disks. Our photometric analysis of the edge-on galaxy UGC 7321 offers a possible breakthrough. This well-studied diffuse, isolated, bulgeless, ultra-thin galaxy is thought to be under-evolved both dynamically and in SF. It is an ideal target to disentangle internal effects in the formation of thick disks and truncations. Our axial light profiles from deep far- and near-ultraviolet (UV; GALEX) images, tracing recent SF, and optical (DESI grz) and NIR (Spitzer 3.6 microns) images, tracing old stellar populations, enable a detailed identification of an outer truncation in all probed wavelengths in both the thin and thick disks. After deprojecting to a face-on view, a sharp truncation signature is found at a stellar density of roughly 1.5 solar masses per square parsec, in agreement with theoretical expectations of gas density SF thresholds. The redder colours beyond the truncation radius are indicative of stellar migration towards the outer regions. We thus show that thick disks and truncations can form via internal mechanisms alone, given the pristine nature of UGC 7321. We report the discovery of a truncation at and above the mid-plane of a diffuse galaxy that is linked to a SF threshold; this poses a constraint on physically-motivated disk size measurements among low-mass galaxies.

Supersoft X-ray sources (SSSs) are known as possible progenitors of Type Ia supernovae. The quasi-periodic variability has been detected in the optical light curves of SSSs. However, the exact origin of such quasi-periodic observable features remains a mystery. In this paper, we aim to reproduce the observed optical quasi-periodic variability of SSSs by proposing a white dwarf (WD) accretion model with a periodic mass transfer caused by the irradiation of supersoft X-ray onto the companion star. Methods. Assuming that a periodic mass transfer from the companion star to the WD can be caused while the supersoft X-ray irradiates the companion star, we used MESA to simulate the WD accretion process and the subsequent WD evolution by adopting a periodic jagged accretion rate. Comparing our results to the optical light curves of a well-observed SSS RX J0513.9-6951, we find that our models can reproduce the quasi-periodic transition between the optical high and low states of RX J0513.9-6951 because the periodic accretion rate can lead to the WD photosphere expands and contracts periodically in our models. In addition, we find that the transitional periods of the SSSs in our models strongly depend on the mass of the accreting WDs. The more massive the WD mass is, the shorter the transitional period. Based on our results, we suggest that the periodic mass transfer caused by the irradiation of supersoft X-ray onto the companion star may be the origin of the observed optical quasi-periodic variability in SSSs. In addition, our results indicate that the observed optical transition period of a SSS may be useful for the rough estimate of the mass of an accreting WD.

A region 140 square degrees toward the Galactic Centre was searched for monochromatic optical light, both pulses shorter than 1 sec and continuous emission. A novel instrument was constructed that acquires optical spectra of every point within 6 square degrees every second, able to distinguish lasers from astrophysical sources. The system consists of a modified Schmidt telescope, a wedge prism over the 0.28-meter aperture, and a fast CMOS camera with 9500 x 6300 pixels. During 2021, a total of 34800 exposures were obtained and analyzed for monochromatic sources, both sub-second pulses and continuous in time. No monochromatic light was found. A benchmark laser with a 10-meter aperture and located 100 light years away would be detected if it had a power more than ~60 megawatt during 1 sec, and from 1000 light years away, 6000 MW is required. This non-detection of optical lasers adds to previous optical SETI non-detections from more than 5000 nearby stars of all masses, from the Solar gravitational lens focal points of Alpha Centauri, and from all-sky searches for broadband optical pulses. These non-detections, along with those of broadband pulses, constitute a growing SETI desert in the optical domain.

Direct gravitational simulations of n-body systems have a time complexity O(n^2), which gets computationally expensive as the number of bodies increases. Distributing this workload to multiple cores significantly speeds up the computation and is the fundamental principle behind parallel computing. This project simulates (evolves) our solar system for the next 1000 years (from 2015 to 3015) on the BlueCrystal supercomputer. The gravitational bodies (planets, moons, asteroids) were successfully simulated, and the initial states (mass, position and velocity vectors) of the solar system objects were obtained via NASA's JPL Horizons web interface. Two parallel computing domains are investigated: shared and distributed memory systems.

The increase in gravitational wave (GW) events has allowed receiving strong lensing image pairs of GWs. However, the wave effect (diffraction and interference) due to the microlens field contaminates the parameter estimation of the image pair, which may lead to a misjudgment of strong lensing signals. To quantify the influence of the microlens field, researchers need a large sample of statistical research. Nevertheless, due to the oscillation characteristic, the Fresnel-Kirchhoff diffraction integral's computational time hinders this aspect's study. Although many algorithms are available, most cannot be well applied to the case where the microlens field is embedded in galaxy/galaxy clusters. This work proposes a faster and more accurate algorithm for studying the wave optics effect of microlenses embedded in different types of strong lensing images. Additionally, we provide a quantitative estimation criterion for the lens plane boundary for the Fresnel-Kirchhoff diffraction integral. This algorithm can significantly facilitate the study of wave optics, particularly in the case of microlens fields embedded in galaxy/galaxy clusters.

Protostars likely accrete material at a highly time variable rate, however, measurements of accretion variability from the youngest protostars are rare, as they are still deeply embedded within their envelopes. Sub-mm/mm observations can trace the thermal response of dust in the envelope to accretion luminosity changes, allowing variations in the accretion rate to be quantified. In this paper, we present contemporaneous sub-mm/mm light curves of variable protostars in Serpens Main, as observed by the ALMA ACA, SMA, and JCMT. The most recent outburst of EC 53 (V371 Ser), an $\sim 18$ month periodic variable, is well-sampled in the SMA and JCMT observations. The SMA light curve of EC 53 is observed to peak weeks earlier and exhibit a stronger amplitude than at the JCMT. Stochastic variations in the ACA observations are detected for SMM 10 IR with a factor $\sim 2$ greater amplitude than as seen by the JCMT. We develop a toy model of the envelope response to accretion outbursts to show EC 53's light curves are plausibly explained by the delay associated with the light travel time across the envelope and the additional dilution of the JCMT response by the incorporation of cold envelope material in the beam. The larger JCMT beam can also wash out the response to rapid variations, which may be occurring for SMM 10 IR. Our work thus provides a valuable proof of concept for the usage of sub-mm/mm observations as a probe of both the underlying accretion luminosity variations and the protostellar environment.

We present morphologies of galaxies at $z\sim9-17$ resolved by JWST/NIRCam $2-5\mu$m imaging. Our sample consists of $25$ galaxy candidates identified by stringent dropout and photo-$z$ criteria in GLASS, CEERS, SMACS J0723, and Stephan's Quintet flanking fields. We perform surface brightness (SB) profile fitting with GALFIT for $6$ bright galaxies with S/N $=10-40$ on an individual basis and for stacked faint galaxies with secure point-spread functions (PSFs) of the NIRCam real data, carefully evaluating systematics by Monte-Carlo simulations. We compare our results with those of previous JWST studies, and confirm that effective radii $r_{\rm e}$ of our measurements are consistent with those of previous measurements at $z\sim 9$. We obtain $r_{\rm e}\simeq 200-300$ pc with the exponential-like profiles, S\'ersic indexes of $n\simeq 1-1.5$, for galaxies at $z\sim 12-17$, indicating that the relation of $r_{\rm e}\propto (1+z)^s$ for $s=-1.19^{+0.16}_{-0.15}$ explains cosmic evolution over $z\sim 0-17$ for $\sim L^*_{z=3}$ galaxies. One bright ($M_{\rm UV}=-21$ mag) galaxy at $z\sim 12$, GL-z12-1, has an extremely compact size with $r_{\rm e}=61 \pm 11$ pc that is surely extended over the PSF. Even in the case that the GL-z12-1 SB is fit by AGN$+$galaxy composite profiles, the best-fit galaxy component is again compact, $r_{\rm e}=78^{+30}_{-12}$ pc that is significantly ($>5\sigma$) smaller than the typical $r_{\rm e}$ value at $z\sim 12$. Comparing with numerical simulations, we find that such a compact galaxy naturally forms at $z\gtrsim 10$, and that frequent mergers at the early epoch produce more extended galaxies following the $r_{\rm e}\propto (1+z)^s$ relation.

The observational counterparts of theoretically predicted first hydrostatic cores (FHSC) have been searched for in the interstellar medium for nearly two decades now. Distinguishing them from other types of more evolved but still embedded objects remains a challenge because these objects have a short lifetime, are small, and embedded in a dense cocoon. One possible lead to finding them is the characterization of the outflows that are launched by these objects. We observed the L1451-mm FHSC candidate with the NOEMA interferometer in order to study the emission of several molecules. A nonlocal thermodynamic equilibrium analysis of the CH$_3$OH detected lines was performed to retrieve the physical conditions of the emitting region around the central source, together with the CH$_3$OH, SiO, CS, and H$_2$CO column densities. Of the targeted molecules, we detected lines of c-C$_3$H$_2$, CH$_3$OH, CS, C$^{34}$S, SO, DCN, DCO$^+$, H$_2$CO, HC$_3$N, HDCO, and SiO. One of the methanol lines appears to be a maser line. The detection of this class I maser and the SiO line in L1451-mm support the presence of a low-velocity and compact outflow. The excitation conditions of the thermal lines of methanol are also compatible with shocks (H$_2$ density of $\sim 3\times 10^6$~cm$^{-3}$ and a temperature higher than 40~K). Although these low-velocity outflows are theoretically predicted by some models of FHSC, these models also predict the shock temperature to be below 20~K, that is, not evaporating methanol. In addition, the predicted velocities would not erode the grains and release silicon in the gas phase. We therefore conclude that these new observations favor the hypothesis that L1451-mm would be at a very early protostellar stage, launching an outflow nearly on the plane of the sky with a higher velocity than is observed.

Water photodissociation in the 114 - 144 nm UV range forms excited OH which emits at mid-infrared wavelengths via highly excited rotational lines. These lines have only been detected with Spitzer in several proto-planetary disks and shocks. Previous studies have shown they are a unique diagnostic for water photodissociation. Thanks to its high sensitivity and angular resolution, the James Webb Space Telescope (JWST) could be able to detect them in other environments such as interstellar Photo-Dissociation Regions (PDRs). We use the Meudon PDR Code to compute the thermal and chemical structure of PDRs. The influence of thermal pressure ($P_{\rm th}/k$ = $n_{\rm H} T_{\rm K}$) and UV field strength on the integrated intensities, as well as their detectability with the JWST are studied in details. OH mid-IR emission is predicted to originate very close to the H$^0$/H$_2$ transition and is directly proportional to the column density of water photodissociated in that layer. Because neutral gas-phase formation of water requires relatively high temperatures ($T_{\rm K} \gtrsim 300~$K), the resulting OH mid-IR lines are primarily correlated with the temperature at this position, and are therefore brighter in regions with high pressure. This imply that these lines are predicted to be only detectable in strongly irradiated PDRs ($G_0^{\rm incident}$ $>$ 10$^3$) with high thermal pressure ($P_{\rm th}/k$ $\gtrsim$ 5$\times$10$^7$ K cm$^{-3}$). In the latter case, OH mid-IR lines are less dependent on the strength of the incident UV field. OH mid-IR lines observable by JWST are a promising diagnostics for dense and strongly irradiated PDRs.

The Large Area Telescope, the primary instrument on the Fermi Gamma-ray Space Telescope, is an imaging, wide field-of-view gamma-ray telescope. After many improvements to the data acquisition and event analysis procedures, it now covers the broad energy range from $\sim 20$ MeV to $\sim 2$ TeV. After more than 13 years of operation since its launch in June 11, 2008, it has provided the best-resolved and deepest portrait of the gamma-ray sky. In this chapter we review the design of the instrument, the data acquisition system, calibration, and performance.

The James Webb Space Telescope (JWST) has discovered a surprising abundance of bright galaxy candidates in the very early Universe (<500Myrs after the Big Bang), calling into question current galaxy formation models. Spectroscopy is needed to confirm the primeval nature of these candidates, as well as to understand how the first galaxies form stars and grow. Here we present deep spectroscopic and continuum ALMA observations towards GHZ2/GLASS-z13, one of the brightest and most robust candidates at z>10, identified in the GLASS-JWST Early Release Science Program. While the lack of dust continuum detection supports its high-redshift nature by ruling out lower redshift dusty interlopers, we do not detect any bright emission line at the position of the target despite covering a total of 30GHz and 98% of the source's redshift probability distribution (z=11.9-13.5). A tentative emission line is identified 0.5arcsec away from the JWST position of GHZ2/GLASS-z13, which would imply a spectroscopic redshift of z=12.117+/-0.012 if associated with the [OIII]88um line. Further confirmation is though necessary to confirm the signal is astrophysical and associated with the target. The current constraints on the oxygen line luminosity place it along (or below) the [OIII]-SFR relation for metal-poor galaxies. The low metallicity and dust content implied by these observations are also consistent with the blue UV slope observed by JWST, which suggest negligible dust attenuation in galaxies at this early epoch. This work illustrates the synergy between JWST and ALMA and paves the way for future spectroscopic surveys of z > 10 galaxy candidates.

The terrestrial planets formed by accretion of small and lunar-Mars-mass objects within the solar system's protoplanetary disk. Terrestrial-planet formation models suggest that a spatially narrow disk could form a massive Venus and Earth and a less massive Mars. Several scenarios may produce such a disk: gas-driven Jupiter migration, early giant planet instability, embryo convergence, and planetesimal/pebble pile-up. However, these models face severe challenges in explaining the simultaneous formation of the four terrestrial planets and other inner solar system properties. Here, we found that chaotic excitation generated by a near-resonant Jupiter-Saturn configuration (2:1 mean motion resonance) before giant planet instability can create a narrow disk, allowing the formation of the terrestrial planets and the asteroid belt. Our simulations showed that this mechanism could typically deplete a massive disk beyond ~1.5 au on a 5-10 Myr timescale. The resulting terrestrial systems reproduced the current orbits and masses of Venus, Earth and Mars. Considering an inner region disk component within ~0.8-0.9 au, several terrestrial systems simultaneously formed analogues of the four terrestrial planets. Our terrestrial systems also frequently satisfied additional constraints: Moon-forming giant impacts occurring after a median ~30-55 Myr, late impactors represented by disk objects formed within 2 au, and effective water delivery during the first 10-20 Myr of Earth's formation. Finally, our model asteroid belt explained the asteroid belt's orbital structure, small mass and taxonomy (S-, C- and D/P-types). Our results show that the chaotic excitation mechanism shaped the solar system's terrestrial planets and the asteroid belt.

The Nancy Grace Roman Space Telescope will use its wide-field instrument to carry out a suite of sky surveys in the near infrared. Several of the science objectives of these surveys, such as the measurement of the growth of cosmic structure using weak gravitational lensing, require exquisite control of instrument-related distortions of the images of astronomical objects. Roman will fly 4kx4k Teledyne H4RG-10 infrared detector arrays. This paper investigates whether the pixel centroids are located on a regular grid by projecting laser speckle patterns through a double slit aperture onto a non-flight detector array. We develop a method to reconstruct the pixel centroid offsets from the stochastic speckle pattern. Due to the orientation of the test setup, only x-offsets are measured here. We test the method both on simulations, and by injecting artificial offsets into the real images. We use cross-correlations of the reconstructions from different speckle realizations to determine how much of the variance in the pixel offset maps is signal (fixed to the detector) and how much is noise. After performing this reconstruction on 64x64 pixel patches, and fitting out the best-fit linear mapping from pixel index to position, we find that there are residual centroid offsets in the x (column) direction from a regular grid of 0.0107 pixels RMS (excluding shifts of an entire row relative to another, which our speckle patterns cannot constrain). This decreases to 0.0097 pix RMS if we consider residuals from a quadratic rather than linear mapping. These RMS offsets include both the physical pixel offsets, as well as any apparent offsets due to cross-talk and remaining systematic errors in the reconstruction. We comment on the advantages and disadvantages of speckle scene measurements as a tool for characterizing the pixel-level behavior in astronomical detectors.

The input of the Solar wind models plays a significant role in accurate solar wind predictions at 1 AU. This work introduces a synthetic magnetogram produced from a dynamo model as an input for Magnetohydrodynamics (MHD) simulations. We perform a quantitative study that compares the Space Weather Modeling Framework (SWMF) results for the observed and the synthetic solar magnetogram input. For each case, we compare the results for Extreme Ultra-Violet (EUV) images and extract the simulation data along the earth trajectory to compare with in-situ observations. We initialize SWMF using the real and synthetic magnetogram for a set of Carrington Rotations (CR)s within the solar cycle 23 and 24. Our results help quantify the ability of dynamo models to be used as input to solar wind models and thus, provide predictions for the solar wind at 1 AU.

Type IV radio burst has been studied for over 50 years. However, the specifics of the radio emission mechanisms is still an open question. In order to provide more information about the emission mechanisms, we studied a moving type IV radio burst with fine structures (spike group) by using the high resolution capability of Low-Frequency Array (LOFAR) on Aug 25, 2014\textbf{ (SOLA-D-21-00188)}. We present a comparison of Nan\c{c}ay RadioHeliograph (NRH) and the first LOFAR imaging data of type IV radio burst. The degree of circular polarization (DCP) is calculated at frequencies in the range 20$\sim$180 MHz using LOFAR data, and it was found that the value of DCP gradually increased during the event, with values of 10\%$\sim$20\%. LOFAR interferometric data were combined with white light observations in order to track the propagation of this type IV. The kinematics shows a westward motion of the radio sources, slower than the CME leading edge. The dynamic spectrum of LOFAR shows a large number of fine structures with duration of less than 1s and high brightness temperature ($T_\mathrm{B}$), i.e. $10^{12}$$\sim$$10^{13}$ K. The gradual increase of DCP supports gyrosynchrotron emission as the most plausible mechanism for the type IV. However, coherent emissions such as Electron Cyclotron Maser (ECM) instability can be responsible for small scale fine structures. Countless fine structures altogether were responsible for such high $T_\mathrm{B}$.

Measuring blackbody parameters for objects hotter than a few 10^4K with optical data alone is common in many astrophysical studies. However this process is prone to large errors because at those temperatures the optical bands are mostly sampling the Rayleigh-Jeans tail of the spectrum. Here we quantify these errors by simulating different blackbodies, sampling them in various bands with realistic measurement errors, and re-fitting them to blackbodies using two different methods and two different priors. We find that when using only optical data, log-uniform priors perform better than uniform priors. Still, measured temperatures of blackbodies above ~35,000K can be wrong by ~10,000K, and only lower limits can be obtained for temperatures of blackbodies hotter than ~50,000K. Bolometric luminosities estimated from optical-only blackbody fits can be wrong by factors of 3-5. When adding space-based ultraviolet data, these errors shrink significantly. For when such data are not available, we provide plots and tables of the distributions of true temperatures that can result in various measured temperatures. It is important to take these distributions into account as systematic uncertainties when fitting hot blackbodies with optical data alone.

We present DM-power, a new method for precisely determining the dispersion measure (DM) of radio bursts, and apply it to the Fast Radio Burst (FRB) source FRB 20180916B. Motivated by the complex structure on multiple time scales seen in FRBs, DM-power optimizes the DM by combining measurements at multiple Fourier frequencies in the power spectrum of the burst. By optimally weighting the measurements at each Fourier frequency, DM-power finds a burst DM that effectively incorporates information on many different burst timescales. We validate this technique on single pulses from the pulsar B0329+54, and then apply it to eleven bursts from FRB~20180916B. The precision of these DM measurements (down to $\sigma_{\rm DM} \sim 0.01~{\rm pc~cm}^{-3}$) are sufficient to measure a statistically significant variation in DM over a $\approx 2$~hr span. While this variation could be the result of electron density variations along the line of sight, it is more like that the observed variation is the result of intrinsic frequency-dependent burst structure that can mimic a dispersive delay.

We constrain the deceleration-acceleration epoch, namely the transition redshift $z_{tr}$, adopting model-independent techniques that utilize a calibrated $E_{\rm p}$-$E_{\rm iso}$ correlation for gamma-ray bursts (GRBs). To do so, in addition to real data points, we employ up to $1000$ simulated observational Hubble data (OHD) points. We then calibrate the $E_{\rm p}$-$E_{\rm iso}$ correlation by means of the well-consolidate B\'ezier polynomial technique, interpolating OHD up to the second order. Once GRB data have been calibrated, we consider two strategies of cosmographic expansions, i.e., first we take a direct Hubble rate expansion around $z_{tr}$, and second the expansion of the deceleration parameter around the same redshift, but with a different order. Employing type Ia supernovae, baryonic acoustic oscillations and GRB data sets, from Monte Carlo analyses we infer tight constraints on $z_{tr}$ and the jerk parameters at $z=z_{tr}$, namely $j_{tr}$. Our results are extremely compatible with previous outcomes and confirm the $\Lambda$CDM predictions, being slightly different in terms of the jerk parameter. In this respect, we conjecture which extensions of the concordance paradigm are possible and we compare our findings with expectations provided by generic dark energy models.

Rapid blue- and red-shifted events (RBEs/RREs) may have an important role in mass-loading and heating the solar corona, but their nature and origin are still debatable. We aim to model these features to learn more about their properties, formation and origin. A realistic three-dimensional (3D) magneto-hydrodynamic (MHD) model of a solar plage region is created. Synthetic H$\alpha$ spectra are generated and the spectral signatures of these features are identified. The magnetic field lines associated with these events are traced and the underlying dynamic is studied. The model reproduces well many properties of RBEs and RREs, such as spatial distribution, lateral movement, length and lifetimes. Synthetic H$\alpha$ line profiles, similarly to observed ones, show strong blue- or red-shift and asymmetries. These line profiles are caused by the vertical component of velocity with magnitudes larger than $30-40$ km/s that appear mostly in the height range of $2-4$ Mm. By tracing magnetic field lines, we show that the vertical velocity that causes the appearance of RBE/RREs to appear is always associated with the component of velocity perpendicular to the magnetic field line. The study confirms the hypothesis that RBEs and RREs are signs of Alfv{\'e}nic waves with, in some cases, a significant contribution from slow magneto-acoustic mode.

The physical motivations, present status, main results in study of cosmic rays and in the field of gamma-ray astronomy as well future plans of the TAIGA-1 (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based gamma-ray astronomy and astroparticle physics at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. The pilot TAIGA-1 complex is located in the Tunka valley, ~50 km West from the southern tip of the lake Baikal.

NGC 602 is a young, low-metallicity star cluster in the "Wing" of the Small Magellanic Cloud. We reveal the recent evolutionary past of the cluster through analysis of high-resolution ($\sim$0.4 pc) Atacama Large Millimeter/submillimeter Array observations of molecular gas in the associated $\textrm{H}\scriptstyle\mathrm{II}$ region N90. We identify 110 molecular clumps ($R <$ 0.8 pc) traced by CO emission, and study the relationship between the clumps and associated young stellar objects (YSOs) and pre-main-sequence (PMS) stars. The clumps have high virial parameters (typical $\alpha_{\rm{vir}} = $ 4-11) and may retain signatures of a collision in the last $\lesssim$8 Myr between $\textrm{H}\scriptstyle\mathrm{I}$ components of the adjacent supergiant shell SMC-SGS 1. We obtain a CO-bright-to-H$_2$ gas conversion factor of $X_{CO,B} = (3.4 \pm 0.2) \times 10^{20}$ cm$^{-2}$ (K km s$^{-1}$)$^{-1}$, and correct observed clump properties for CO-dark H$_2$ gas to derive a total molecular gas mass in N90 of $16,600 \pm 2,400 \ M_\odot$. We derive a recent ($\lesssim 1$ Myr) star formation rate of $130 \pm 30 \ M_{\odot}$ Myr$^{-1}$ with an efficiency of 8 $ \pm$ 3\% assessed through comparing total YSO mass to total molecular gas mass. Very few significant radial trends exist between clump properties or PMS star ages and distance from NGC 602. We do not find evidence for a triggered star formation scenario among the youngest ($\lesssim$2 Myr) stellar generations, and instead conclude that a sequential star formation process in which NGC 602 did not directly cause recent star formation in the region is likely.

Understanding the noise in gravitational-wave detectors is central to detecting and interpreting gravitational-wave signals. Glitches are transient, non-Gaussian noise features that can have a range of environmental and instrumental origins. The Gravity Spy project uses a machine-learning algorithm to classify glitches based upon their time-frequency morphology. The resulting set of classified glitches can be used as input to detector-characterisation investigations of how to mitigate glitches, or data-analysis studies of how to ameliorate the impact of glitches. Here we present the Gravity Spy analysis of data up to the end of the third observing run of Advanced LIGO. We classify 233981 glitches from LIGO Hanford and 379805 glitches from LIGO Livingston into morphological classes. We find that the distribution of glitches differs between the two LIGO sites. This highlights the potential need for studies of data quality to be individually tailored to each gravitational-wave observatory.

The Advanced LIGO/Virgo interferometers have observed $\sim 100$ gravitational-wave transients enabling new questions to be answered about relativity, astrophysics, and cosmology. However, many of our current procedures for computing these constraints will not scale well with the increased size of future transient catalogs. We introduce a novel hybrid sampling method in order to more efficiently perform parameterized tests of general relativity with gravitational-wave signals. Applying our method to the binary black hole merger GW150914 and simulated signals we find that our method is approximately an order of magnitude more efficient than the current method with conservative settings for our hybrid analysis. While we have focused on the specific problem of measuring potential deviations from relativity, our method is of much wider applicability to any problem that can be decomposed into a simple and more complex model(s).

In the framework of Thomas-Fermi approximation, we study systematically the EOSs and microscopic structures of neutron star matter in a vast density range with $n_\mathrm{b}\approx 10^{-10}$-2 $\mathrm{fm}^{-3}$, where various covariant density functionals are adopted, i.e., those with nonlinear self couplings (NL3, PK1, TM1, GM1, MTVTC) and density-dependent couplings (DD-LZ1, DDME-X, PKDD, DD-ME2, DD2, TW99). It is found that the EOSs generally coincide with each other at $n_\mathrm{b}\lesssim 10^{-4}$ fm${}^{-3}$ and 0.1 fm${}^{-3}\lesssim n_\mathrm{b} \lesssim 0.3$ fm${}^{-3}$, while in other density regions they are sensitive to the effective interactions between nucleons. By adopting functionals with larger slope of symmetry energy $L$, the curvature parameter $K_\mathrm{sym}$ and neutron drip density generally increase, while the droplet size, proton number of nucleus, core-crust transition density, and onset density of non-spherical nuclei decrease. All functionals predict neutron stars with maximum masses exceeding the two-solar-mass limit, while those of DD2, DD-LZ1, DD-ME2, and DDME-X predict optimum neutron star radii according to the observational constraints. Nevertheless, the corresponding skewness coefficients $J$ are much lager than expected, while only the functionals MTVTC and TW99 meet the start-of-art constraints on $J$. More accurate measurements on the radius of PSR J0740+6620 and the maximum mass of neutron stars are thus essential to identify the functional that satisfies all constraints from nuclear physics and astrophysical observations. Approximate linear correlations between neutron stars' radii at $M=1.4 M_{\odot}$ and $2 M_{\odot}$, the slope $L$ and curvature parameter $K_\mathrm{sym}$ of symmetry energy are observed as well, which is mainly attributed to the curvature-slope correlations in the functionals adopted here.

The difficulty in describing the equation of state (EoS) for nuclear matter at densities above the saturation density ($\rho_0$) has led to the emergence of a multitude of models based on different assumptions and techniques. These EoSs, when used to describe a neutron star (NS), lead to differing values of observables. An outstanding goal in astrophysics is to constrain the dense matter EoS by exploiting astrophysical and gravitational wave measurements. Nuclear matter parameters appear as Taylor coefficients in the expansion of the EoS around the saturation density of symmetric and asymmetric nuclear matter, and provide a physically-motivated representation of the EoS. In this paper, we introduce a deep learning-based methodology to predict key neutron star observables such as the NS mass, NS radius, and tidal deformability from a set of nuclear matter parameters. Using generated mock data, we confirm that the neural network model is able to accurately capture the underlying physics of finite nuclei and replicate inter-correlations between the symmetry energy slope, its curvature and the tidal deformability arising from a set of physical constraints. We also perform a systematic Bayesian estimation of NMPs in light of recent observational data with the trained neural network and study the effects of correlations among these NMPs. We show that by not considering inter-correlations arising from finite nuclei constraints, an intrinsic uncertainty of upto 30% can be observed on higher-order NMPs.

We considered the Tsallis holographic dark energy model in frames of Nojiri-Odintsov gravity with $f(R)=R+\lambda R^2-\sigma{\mu}/{R}$. For IR cutoff event horizon is taken. The cosmological evolution of such universe is investigated for various initial conditions and values of parameters. The dependence of the Hubble parameter $H$ from time in the future has an oscillations. It is shown that for $\mu \neq 0$ appearance of singularities are typical and the time up to these singularities can be relatively small from cosmological viewpoint. The singularity is associated with the zero of second deribative of $f(R)$ on $R$. It is interesting to note that these models can describe observational data from Ia supernovae astrophysics and dependence of the Hubble parameter from redshift $z$ at least not worse than canonical $\Lambda$CDM model.

The measurement of environmental neutrons is particularly important in the search for new physics, such as dark matter particles, because neutrons constitute an often-irreducible background source. The measurement of the neutron energy spectra in the sub-MeV scale is technically difficult because it requires a very good energy resolution and a very high $\gamma$-ray rejection power. In this study, we used a super-fine-grained nuclear emulsion, called Nano Imaging Tracker (NIT), as a neutron detector. The main target of neutrons is the hydrogen (proton) content of emulsion films. Through a topological analysis, proton recoils induced by neutron scattering can be detected as tracks with sub-micrometric accuracy. This method shows an extremely high $\gamma$-ray rejection power, at the level of $3 \times 10^7 ~ \gamma ~ \rm{cm}^{-2}$, which is equivalent to 3 years accumulation of environmental $\gamma$-rays, and a very good energy and direction resolution even in the sub-MeV energy region. In order to carry out this measurement with sufficient statistics, we upgraded the automated scanning system to achieve a speed of 250 g/year/machine. We calibrated the detector performance of this system with 880 keV monochromatic neutrons: a very good agreement with the expectation was found for all the relevant kinematic variables. The application of the developed method to a sample exposed at the INFN Gran Sasso surface laboratory provided the first measurement of sub-MeV environmental neutrons with a flux of $(5.9 \pm 1.2) \times 10^{-3} \rm{cm}^{-2} \rm{s}^{-1}$ in the proton energy range between 0.25 and 1 MeV (corresponds to neutron energy range between 0.25 and 10 MeV), consistent with the prediction. The neutron energy and direction distributions also show a good agreement.

In this contribution I discuss the Kapteyn Astronomical Laboratory during the period of Pieter Johannes van Rhijn's directorate, which lasted from 1921 to 1957. It had developed under the founder Jacobus Cornelius Kapteyn into one of the leading astronomical research institutes in the world. When van Rhijn took over at the retirement of Kapteyn, it was in the process of coordinating Kapteyn's Plan of Selected Areas. Van Rhijn's research was solid and professional work, but in his papers he invariably stopped before discussing how his findings did fit into the larger scheme of things. He maybe was unimaginative but it did lack the link to the larger view towards the emerging picture of the structure of the Galaxy. Van Rhijn was unfortunate to be hampered throughout almost his complete directorate by factors, that severely limited his attempts to obtain more funding in spite of local support by his university. These were of course in the first place the Great Depression of the 1930s and the Second World War and its aftermath, while during most of the 1940s he suffered from tuberculosis. But also the remote location of Groningen compared to Leiden, where a major infrastructure led by three important protegees of Kapteyn was in place, and the governmental bias towards support for Leiden over Groningen was an important factor. Finally I examine the developments in the 1950s and the circumstances that made Adriaan Blaauw accept his appointment as van Rhijn's successor in 1957 and initiate the beginnings of the revival under his leadership.

We constrain Europa's tenuous atmosphere on the subsolar hemisphere by combining two sets of observations: oxygen emissions at 1304 {\AA} and 1356 {\AA} from Hubble Space Telescope (HST) spectral images, and Galileo magnetic field measurements from its closest encounter, the E12 flyby. We describe Europa's atmosphere with three neutral gas species: global molecular ($\mathrm{O_2}$) and atomic oxygen (O), and localized water ($\mathrm{H_2O}$) present as a near-equatorial plume and as a stable distribution concentrated around the subsolar point on the moon's trailing hemisphere. Our combined modelling based on the ratio of OI 1356 {\AA} to OI 1304 {\AA} emissions from Roth (2021) and on magnetic field data allows us to derive constraints on the density and location of $\mathrm{O_2}$ and $\mathrm{H_2O}$ in Europa's atmosphere. We demonstrate that $50\%$ of the $\mathrm{O_2}$ and between $50\%$ and $75\%$ of the $\mathrm{H_2O}$ abundances from Roth (2021) are required to jointly explain the HST and Galileo measurements. These values are conditioned on a column density of $\mathrm{O}$ close to the upper limit of $6 \times10^{16}~\mathrm{m}^{-2}$ derived by Roth (2021), and on a strongly confined stable $\mathrm{H_2O}$ atmosphere around the subsolar point. Our analysis yields column densities of $1.2 \times10^{18}~\mathrm{m}^{-2}$ for $\mathrm{O_2}$, and $1.5 \times10^{19}~\mathrm{m}^{-2}$ to $2.2 \times10^{19}~\mathrm{m}^{-2}$ at the subsolar point for $\mathrm{H_2O}$. Both column densities however still lie within the uncertainties of Roth (2021). Our results provide additional evidence for the existence of a stable $\mathrm{H_2O}$ atmosphere at Europa.

We made global fits of the inert Higgs doublet model (IDM) in the light of collider and dark matter search limits and the requirement for a strongly first-order electroweak phase transition (EWPT). These show that there are still IDM parameter spaces compatible with the observational constraints considered. In particular, the data and theoretical requirements imposed favour the hypothesis for the existence of a scalar dark matter candidate around 100 GeV. This is mostly due to the pull towards lower masses by the EWPT constraint. The impact of electroweak precision measurements, the dark matter direct detection limits, and the condition for obtaining a strongly enough first-order EWPT, all have strong dependence, sometimes in opposing directions, on the mass splittings between the IDM scalars.