Papers for Monday, Jan 02 2023

Supermassive black holes (SMBHs) are thought to originate from early Universe seed black holes of mass $M_\mathrm{BH} \sim 10^2$-10$^5$ M$_{\odot}$ and grown through cosmic time. Such seeds could be powering the active galactic nuclei (AGN) found in today's dwarf galaxies. However, probing a connection between the early seeds and local SMBHs has not yet been observationally possible. Massive black holes hosted in dwarf galaxies at intermediate redshifts, on the other hand, may represent the evolved counterparts of the seeds formed at very early times. We present a sample of seven broad-line AGN in dwarf galaxies with a spectroscopic redshift ranging from z=0.35 to z=0.93. The sources are drawn from the VIPERS survey as having a stellar mass ($M_\mathrm{*}$) LMC-like derived from spectral energy distribution fitting and they are all star-forming galaxies. Six of these sources are also X-ray AGN. The AGN are powered by SMBHs of $>10^7$ M$_{\odot}$, more massive than expected from the $M_\mathrm{BH}$-$M_\mathrm{*}$ scaling relation of AGN. Based on semi-analytical simulations, we find that these objects are likely overmassive with respect to their hosts since early times (z$>$4), independently of whether they formed as heavy ($\rm \sim 10^5$ M$_\odot$) or light ($\rm \sim 10^2$ M$_\odot$) seed black holes. In our simulations, these objects tend to grow faster than their host galaxies, contradicting models of synchronized growth. The host galaxies are found to possibly evolve into massive systems by z$\sim$0, indicating that local SMBHs in massive galaxies could originate in dwarf galaxies hosting seed black holes at higher z.

We examine a type of features in the primordial scalar power spectrum, namely, the bump-like feature(s) that arise as a result of burst(s) of particle production during inflation. The latest CMB observations by Planck 2018 can accommodate such features. In the near future, observations of redshifted 21 cm signal from the epoch of reionization can put additional constraints on inflation models by exploiting the expected tomographic information across a wide range of co-moving wave-numbers. In this work, we study the potential of upcoming observational data from SKA-Low to constrain the parameters of the primordial power spectrum with bump-like features. We use simulated mock data expected from SKA-Low, with uncertainties estimated from different foreground removal models, and constrain the parameters of primordial features within a Bayesian framework. We study two scenarios: in the first scenario, where the astrophysical parameters relevant to the evolution of the 21 cm signal are known, we find that 21 cm power spectra do have the potential to probe the primordial bump-like features. As the input amplitude of the bump is decreased below roughly 10% of the amplitude of the primordial power spectrum without the bump, the uncertainties in the recovered values for both amplitude and location of the bump are found to increase, and the recovered values of the location of the bump also get increasingly more biased towards higher values. Hence, it becomes harder to constrain these parameters. In the second scenario, we analyze the achievable constraints on primordial features when two of the astrophysical parameters, namely, minimum halo mass and ionizing efficiency are uncertain. We find that the effect of the bump on the shape and the amplitude of the 21 cm power spectrum is distinct from the impact of varying the astrophysical parameters, and hence they may potentially be distinguished.

Infrared spectroscopic observations from the ground must be corrected from telluric contamination to make them ready for scientific analyses. However, telluric correction is often a tedious process that requires significant expertise to yield accurate results in a reasonable time frame. To solve these inconveniences, we present a new method for telluric correction that employs a roughly simultaneous observation of a Vega analog to measure atmospheric transmission. After continuum reconstruction and spectral fitting, the stellar features are removed from the observed Vega-type spectrum and the result is used for cancelling telluric absorption features on science spectra. This method is implemented as TelCorAl (Telluric Correction from Alicante), a Python-based web application with a user-friendly interface, whose beta version will be released soon.

Here we present the observations and the first light curve analysis of the short-period variable star NSVS 2983201. Using the light curve numerical modeling we find the best fitting model to be of shallow (ff=10%) contact binary configuration of mass ratio q=0.36. The light curve of the system experiences the O'Connell effect, which led to identifying a large circumpolar starspot. With a careful multi-cases analysis we search for the physical parameters of the system. We find the results obtained with the different methods to be close, but not overlapping. This system will be scheduled for the further monitoring.

The volcanism plays an important part in mass exchange circle to bring matter from core of planet to atmosphere. Thus, it is a possible method to research the change of elements abundance in atmosphere by modeling the process of volatiles from volcanism get through and mix in atmosphere, which is the focused point of this article. This article penetrates from the generation of volatiles, talks the species, mass, and mole fractions of different typical elements in magma. Then a diffusion progress model of volatiles was built to quantify the abundance of elements with altitude. And the quantitative models of element abundance at different heights are obtained.

This present article is dedicated to thoroughly exploring the competency of the synergy of the upcoming Cosmic Microwave Background (CMB) missions and Square Kilometre Array (SKA) surveys in detecting features in the primordial power spectrum. Features are by definition specific scale-dependent modifications to the minimal power-law power spectrum. The functional form of the features depends on the inflationary scenarios taken into consideration. The identification of any conclusive deviation from the feature-less power-law power spectrum will allow us to largely fathom out the microphysics of the primordial universe. Here, we consider three vital theoretically motivated feature models, namely, Sharp feature signal, Resonance feature signal, and Bump feature. To investigate these features, we associate each feature model with a specific scale-dependent function called a template. Here we explore three distinct fiducial models for each feature model and for each fiducial model we compare the sensitivity of 36 different combinations of the cosmological surveys. We implement the Fisher matrix forecast method to obtain the possible constraints on the feature model parameters for the future CMB missions, namely, PICO, CORE-M5, LiteBIRD and CMB-S4 in synergy with upcoming SKA surveys, wherein we explore SKA-Cosmic Shear and SKA-Intensity Mapping surveys. Furthermore, the significance of combining EUCLID-Galaxy surveys with the SKA-Intensity Mapping survey is also explored. To consider the feasibility of propagating theoretical uncertainties of nonlinear scales in estimating the uncertainties on the feature parameters, we adopt redshift dependent upper limits of scales. To demonstrate the relative sensitivities of these future surveys towards the parameters of the feature models, we present a comparative analysis of all three feature models.

A systematic way of data reduction for the Nishiharima Infrared Camera (NIC) polarimetry mode has been devised and implemented to an open software called NICpolpy in the programming language python (tested on version 3.8--3.10 as of writing). On top of the classical methods, including vertical pattern removal, a new way of diagonal pattern (Fourier pattern) removal has been implemented. Each image undergoes four reduction steps, resulting in "level 1" to "level 4" products, as well as nightly calibration frames. A simple tutorial and in-depth descriptions are provided, as well as the descriptions of algorithms. The dome flat frames (taken on UT 2020-06-03) were analyzed, and the pixel positions vulnerable to flat error were found. Using the dark and flat frames, the detector parameters, gain factor (the conversion factor), and readout noise are also updated. We found gain factor and readout noise are likely constants over pixel or "quadrant".

We present laboratory mid-infrared transmission/absorption spectra obtained from matrix of the hydrated Murchison CM meteorite experimentally shocked at peak pressures of 10 to 49 GPa, and compare them to astronomical observations of circumstellar dust in different stages of the formation of planetary systems. The laboratory spectra of the Murchison samples exhibit characteristic changes in the infrared features. A weakly shocked sample (shocked at 10 GPa) shows almost no changes from the unshocked sample dominated by hydrous silicate (serpentine). Moderately shocked samples (21 to 34 GPa) have typical serpentine features gradually replaced by bands of amorphous material and olivine with increasing shock pressure. A strongly shocked sample (36 GPa) shows major changes due to decomposition of the serpentine and due to devolatilization. A shock melted sample (49 GPa) shows features of olivine recrystallized from melted material. The spectra of highly shocked Murchison samples (36 and 49 GPa) are similar to those of dust in the debris disks of HD113766 and HD69830, and the transitional disk of HD100546. The moderately shocked samples (21 to 34 GPa) exhibit spectra similar to those of dust in the debris disks of Beta Pictoris and BD+20307, and the transitional disk of GM Aur. An average of the spectra of all Murchison samples (0 to 49 GPa) has a similarity to the spectrum of the older protoplanetary disk of SU Auriga. In the gas-rich transitional and protoplanetary disks, the abundances of amorphous silicates and gases have widely been considered to be a primary property. However, our study suggests that impact processing may play a significant role in generating secondary amorphous silicates and gases in those disks. Infrared spectra of the shocked Murchison samples are also suggesting that the comets also contain shocked Murchison-like material.

In the coldest (10--20 K) regions of the interstellar medium, the icy surfaces of interstellar grains serve as solid-state supports for chemical reactions. Among their plausible roles, that of third body is advocated, in which the reaction energies of surface reactions dissipate throughout the grain, stabilizing the product. This energy dissipation process is poorly understood at the atomic scale, although it can have a high impact on Astrochemistry. Here, we study, by means of quantum mechanical simulations, the formation of NH3 via successive H-additions to atomic N on water ice surfaces, paying special attention to the third body role. We first characterize the hydrogenation reactions and the possible competitive processes (i.e., H-abstractions), in which the H-additions are more favourable than the H-abstractions. Subsequently, we study the fate of the hydrogenation reaction energies by means of ab initio molecular dynamics simulations. Results show that around 58--90\% of the released energy is quickly absorbed by the ice surface, inducing a temporary increase of the ice temperature. Different energy dissipation mechanisms are distinguished. One mechanism, more general, is based on the coupling of the highly excited vibrational modes of the newly formed species and the libration modes of the icy water molecules. A second mechanism, exclusive during the NH$_3$ formation, is based on the formation of a transient H$_3$O$^+$/NH$_2^-$ ion pair, which significantly accelerates the energy transfer to the surface. Finally, the astrophysical implications of our findings relative to the interstellar synthesis of NH$_3$ and its chemical desorption into the gas are discussed.

Wave (fuzzy) dark matter consists of ultralight bosons ($m \sim 10^{-22} \textrm{--} 10^{-20}\,{\rm eV}$), featuring a compact solitonic core at the centre of a granular halo. Here we extend this model to a two-component wave dark matter, with distinct particle masses and coupled only through gravity, and investigate the resulting soliton-halo structure via cosmological simulations. Specifically, we assume wave dark matter contains $75$ per cent major component and $25$ per cent minor component, fix the major-component particle mass to $m_{\rm major}=1\times10^{-22}\,{\rm eV}$, and explore two different minor-component particle masses with $m_{\rm major}:m_{\rm minor}=3:1$ and $1:3$, respectively. For $m_{\rm major}:m_{\rm minor}=3:1$, we find that (i) the major- and minor-component solitons coexist, have comparable masses, and are roughly concentric. (ii) The soliton peak density is significantly lower than the single-component counterpart, leading to a much smoother soliton-to-halo transition and rotation curve. (iii) The combined soliton mass of both components follows the same single-component core-halo mass relation. In dramatic contrast, for $m_{\rm major}:m_{\rm minor}=1:3$, we find that a minor-component soliton cannot form with the presence of a stable major-component soliton; the total density profile, for both halo and soliton, is thus dominated by the major component and closely follows the single-component case. To support this finding, we propose a toy model to illustrate that it is difficult to form a soliton in a hot environment associated with a deep gravitational potential. The work demonstrates the extra flexibility added to the multi-component wave dark matter model is capable of resolving observational tensions over the single-component model while retaining key features of the single-component model.

Calcium-rich supernovae (Ca-rich SNe) are faint, rapidly evolving transients whose progenitor system is yet to be determined. We derive the $\gamma$-ray deposition histories of five Ca-rich SNe from the literature in order to place constraints on possible progenitor systems. We find that the $ \gamma $-ray escape time, $ t_0 $, of the Ca-rich SNe sample is $\approx35$-$65 \,\rm{d}$, within the unoccupied region between Type Ia SNe and stripped envelope supernovae (SESNe). The $ t_0$-$M_\mathrm{Ni56} $ distribution of these SNe, where $M_\mathrm{Ni56}$ is the synthesised $^{56}$Ni mass in the explosion, creates a continuum between the Type Ia and SESNe $ t_0$-$M_\mathrm{Ni56} $ distribution, hinting at a possible connection between all the events. By comparing our results to models from the literature, we were able to determine that helium shell detonation models and core-collapse models of ultra-stripped stars are unlikely to explain Ca-rich SNe, since the gamma-ray escape time in these models is smaller than the observed values. Models that agree with the observed $ t_0$-$M_\mathrm{Ni56} $ distribution are explosions of low mass, $M\approx0.75$-$0.8\,M_\odot $, white dwarfs and core-collapse models of stripped stars with an ejecta mass of $M\approx1$-$3\,M_{\odot}$.

We use a cosmology-independent method to calibrate gamma-ray burst (GRB) from the observational Hubble data (OHD) which obtained with the cosmic chronometers method. By using Gaussian Process to reconstruct OHD, we calibrate the Amati relation ($E_{\rm p}$--$E_{\rm iso}$) to construct a GRB Hubble diagram with the A118 data set, and constrain Dark Energy models in a flat space with the Markov Chain Monte Carlo numerical method. With the cosmology-independent GRBs at $1.4<z\leq8.2$ in the A118 data set and the Pantheon sample of type Ia supernovae (SNe Ia) at $0.01<z\leq2.3$, we obtained $\Omega_{\rm m}$ = $0.398^{+0.028}_{-0.021}$, $h$ = $0.702^{+0.0035}_{-0.0035}$, $w$ = $-1.33^{+0.14}_{-0.12}$, $w_a$ = $-0.97^{+0.57}_{-0.57}$ for the flat CPL model at the 1$\sigma$ confidence level. We find that the $\Lambda$CDM model is favoured respect to the $w$CDM model and the CPL model with the selection criteria.

We construct seismic models of the four double-mode radial $\delta$ Scuti stars adopting opacities from three databases: OPAL, OP and OPLIB. The aim is to find the models that fit the observed frequencies of the two radial modes and have the effective temperature and luminosity consistent with the observed values. Using the Bayesian analysis based on Monte Carlo simulations, we obtain that only the OPAL seismic models are caught within the observed error box in the HR diagram. Seismic models computed with the OP and OPLIB data are much cooler and less luminous. By including the relative amplitude of the bolometric flux variations (the so-called parameter $f$) into these simulations, we constrain the efficiency of convection in the envelopes, described by the mixing length parameter $\alpha_{\rm MLT}$. We get $\alpha_{\rm MLT}\approx 0.5$ for BP Peg, AE UMa and RV Ari (Population I stars) and $\alpha_{\rm MLT}\approx 1.0$ for SX Phe (Population II star). For all the stars, overshooting from the convective core seems inefficient. A similar effect of opacity should occur also for classical Cepheids or RR Lyr stars that are used as standard candles to measure the universe.

We present a new description of cosmological evolution of the primordial magnetic field under the condition that it is non-helical and its energy density is larger than the kinetic energy density. We argue that the evolution can be described by four different regimes, according to whether the decay dynamics is linear or not, and whether the dominant dissipation term is the shear viscosity or the drag force. Using this classification and conservation of the Hosking integral, we present analytic models to adequately interpret the results of various numerical simulations of field evolution with variety of initial conditions. It is found that, contrary to the conventional wisdom, the decay of the field is generally slow, exhibiting the inverse transfer, because of the conservation of the Hosking integral. Using the description proposed here, we may trace the intermediate evolution history of the magnetic field and clarify whether each process governing its evolution is frozen or not, which is essential to follow the evolution of relatively weak magnetic fields.

Modeling of transient events in the solar atmosphere requires the confluence of 3 critical elements: (1) model sophistication, (2) data availability, and (3) data assimilation. This white paper describes required advances that will enable statistical flare and CME forecasting (e.g. eruption probability and timing, estimation of strength, and CME details, such as speed and magnetic field orientation) similar to weather prediction on Earth.

Magnetic flux ropes (MFRs), sets of coherently twisted magnetic field lines, are believed as core structures of various solar eruptions. Their evolution plays an important role to understand the physical mechanisms of solar eruptions, and can shed light on adverse space weather near the Earth. However, the erupting MFRs are occasionally prevented by strong overlying magnetic fields, and the MFR evolution during the descending phase in the confined cases is lack of attention. Here, we present the deformation of an erupting MFR accompanied by a confined double-peaked solar flare. The first peak corresponded to the MFR eruption in a standard flare model, and the second peak was closely associated with the flashings of an underlying sheared arcade (SA), the reversal slipping motion of the L-shaped flare ribbon, the falling of the MFR, and the shifting of top of filament threads. All results suggest that the confined MFR eruption involved in two-step magnetic reconnection presenting two distinct episodes of energy release in the flare impulsive phase, and the latter magnetic reconnection between the confined MFR and the underlying SA caused the deformation of MFR.

The D-Egg, an acronym for ``Dual optical sensors in an Ellipsoid Glass for Gen2,'' is one of the optical modules designed for future extensions of the IceCube experiment at the South Pole. The D-Egg has an elongated-sphere shape to maximize the photon-sensitive effective area while maintaining a narrow diameter to reduce the cost and the time needed for drilling of the deployment holes in the glacial ice for the optical modules at depths up to 2700 meters. The D-Egg design is utilized for the IceCube Upgrade, the next stage of the IceCube project also known as IceCube-Gen2 Phase 1, where nearly half of the optical sensors to be deployed are D-Eggs. With two 8-inch high-quantum efficiency photomultiplier tubes (PMTs) per module, D-Eggs offer an increased effective area while retaining the successful design of the IceCube digital optical module (DOM). The convolution of the wavelength-dependent effective area and the Cherenkov emission spectrum provides an effective photodetection sensitivity that is 2.8 times larger than that of IceCube DOMs. The signal of each of the two PMTs is digitized using ultra-low-power 14-bit analog-to-digital converters with a sampling frequency of 240 MSPS, enabling a flexible event triggering, as well as seamless and lossless event recording of single-photon signals to multi-photons exceeding 200 photoelectrons within 10 nanoseconds. Mass production of D-Eggs has been completed, with 277 out of the 310 D-Eggs produced to be used in the IceCube Upgrade. In this paper, we report the des\ ign of the D-Eggs, as well as the sensitivity and the single to multi-photon detection performance of mass-produced D-Eggs measured in a laboratory using the built-in data acquisition system in each D-Egg optical sensor module.

We review the recent observations of protoplanetary disks together with relevant theoretical studies with an emphasis on the evolution of volatiles. In the last several years Atacama Large Millimeter/submillimeter Array (ALMA) provided evidence of grain growth, gas-dust decoupling, and sub-structures such as rings and gaps in the dust continuum. Molecular line observations revealed radial and vertical distributions of molecular abundances and also provided significant constraints on the gas dynamics such as turbulence. While sub-millimeter and millimeter observations mainly probe the gas and dust outside the radius of several au, ice and inner warm gas are investigated at shorter wavelengths. Gas and dust dynamics are key to connecting these observational findings. One of the emerging trends is inhomogeneous distributions of elemental abundances, most probably due to dust-gas decoupling.

We investigate the impact of the surface brightness (SB) limit on the galaxy stellar mass functions (GSMFs) using mock surveys generated from the Horizon Run 5 (HR5) simulation. We compare the stellar-to-halo-mass relation, GSMF, and size-stellar mass relation of the HR5 galaxies with empirical data and other cosmological simulations. The mean SB of simulated galaxies are computed using their effective radii, luminosities, and colors. To examine the cosmic SB dimming effect, we compute $k$-corrections from the spectral energy distributions of individual simulated galaxy at each redshift, apply the $k$-corrections to the galaxies, and conduct mock surveys based on the various SB limits. We find that the GSMFs are significantly affected by the SB limits at a low-mass end. This approach can ease the discrepancy between the GSMFs obtained from simulations and observations at $0.625\le z\le 2$. We also find that a redshift survey with a SB selection limit of $\left<\mu_r\right>^e =$ 28 mag arcsec${}^{-2}$ will miss 20% of galaxies with $M_\star^g=10^{9}~{\rm M_\odot}$ at $z=0.625$. The missing fraction of low-surface-brightness galaxies increases to 50%, 70%, and 98% at $z=0.9$, 1.1, and 1.9, respectively, at the SB limit.

Large-scale solar eruptive activities have a close relationship with coronal magnetic flux ropes. Previous numerical studies have found that the equilibrium of a coronal flux rope system could be disrupted if the axial magnetic flux of the rope exceeds a critical value, so that the catastrophe occurs, initiating the flux rope to erupt. Further studies discovered that the catastrophe does not necessarily exist: the flux rope system with certain photospheric flux distributions could be non-catastrophic. It is noteworthy that most previous numerical studies are under the ideal magnetohydrodynamic (MHD) condition, so that it is still elusive whether there is the catastrophe associated with the critical axial flux if magnetic reconnection is included in the flux rope system. In this paper, we carried out numerical simulations to investigate the evolutions of coronal magnetic rope systems under the ideal MHD and the resistive condition. Under the ideal MHD condition, our simulation results demonstrate that the flux rope systems with either too compact or too weak photospheric magnetic source regions are non-catastrophic versus varying axial flux of the rope, and thus no eruption could be initiated; if there is magnetic reconnection in the rope system, however, those flux rope systems could change to be capable of erupting via the catastrophe associated with increasing axial flux. Therefore, magnetic reconnection could significantly influence the catastrophic behaviors of flux rope system. It should be both the magnetic topology and the local physical parameters related to magnetic reconnection that determine whether the increasing axial flux is able to cause flux rope eruptions.

The sunspot cycle is the magnetic cycle of the Sun produced by the dynamo process. A central idea of the solar dynamo is that the toroidal and the poloidal magnetic fields of the Sun sustain each other. We discuss the relevant observational data both for sunspots (which are manifestations of the toroidal field) and for the poloidal field of the Sun. We point out how the differential rotation of the Sun stretches out the poloidal field to produce the toroidal field primarily at the bottom of the convection zone, from where parts of this toroidal field may rise due to magnetic buoyancy to produce sunspots. In the flux transport dynamo model, the decay of tilted bipolar sunspot pairs gives rise to the poloidal field by the Babcock--Leighton mechanism. In this type of model, the meridional circulation of the Sun, which is poleward at the solar surface and equatorward at the bottom of the convection zone, plays a crucial role in the transport of magnetic fluxes. We finally point out that various stochastic fluctuations associated with the dynamo process may play a key role in producing the irregularities of the sunspot cycle.

The rotational line survey by ALMA (Atacama Large Millimeter/submillimeter Array) recently revealed the presence of i-C3H7CN (i-PrCN) and n-C3H7CN (n-PrCN) in 3-mm atmospheric window between 84 to 111 GHz towards the hot core region Sagittarius B2(N) (Sgr B2(N)). This was the first interstellar detection of a linear straight chain molecule. In this light, we report the rotational spectra of C5H12 isomeric group in the same frequency range. We performed quantum chemical calculations for spectroscopic parameters. The pure rotational spectrum of the species has been simulated using the PGOPHER program. The rotational spectrum of this molecule makes it a good candidate for future astronomical detections since the radio lines can be calculated to very high accuracy in mm/sub-mm wave region.

Redshift measurement has always been a constant need in modern astronomy and cosmology. And as new surveys have been providing an immense amount of data on astronomical objects, the need to process such data automatically proves to be increasingly necessary. In this article, we use simulated data from the Dark Energy Survey, and from a pipeline originally created to classify supernovae, we developed a linear regression algorithm optimized through novel automated machine learning (AutoML) frameworks achieving an error score better than ordinary data pre-processing methods when compared with other modern algorithms (such as XGBOOST). Numerically, the photometric prediction RMSE of type Ia supernovae events was reduced from 0.16 to 0.09 and the RMSE of all supernovae types decreased from 0.20 to 0.14. Our pipeline consists of four steps: through spectroscopic data points we interpolate the light curve using Gaussian process fitting algorithm, then using a wavelet transform we extract the most important features of such curves; in sequence we reduce the dimensionality of such features through principal component analysis, and in the end we applied super learning techniques (stacked ensemble methods) through an AutoML framework dedicated to optimize the parameters of several different machine learning models, better resolving the problem. As a final check, we obtained probability distribution functions (PDFs) using Gaussian kernel density estimations through the predictions of more than 50 models trained and optimized by AutoML. Those PDFs were calculated to replicate the original curves that used SALT2 model, a model used for the simulation of the raw data itself.

Line intensity mapping (LIM) is a promising probe to study star formation, the large-scale structure of the Universe, and the epoch of reionization (EoR). Since carbon monoxide (CO) is the second most abundant molecule in the Universe except for molecular hydrogen ${\rm H}_2$, it is suitable as a tracer for LIM surveys. However, just like other LIM surveys, CO intensity mapping also suffers strong foreground contamination that needs to be eliminated for extracting valuable astrophysical and cosmological information. In this work, we take $^{12}$CO($\it J$=1-0) emission line as an example to investigate whether deep learning method can effectively recover the signal by removing the foregrounds. The CO(1-0) intensity maps are generated by N-body simulations considering CO luminosity and halo mass relation, and we discuss two cases with median and low CO signals by comparing different relations. We add foregrounds generated from real observations, including thermal dust, spinning dust, free-free, synchrotron emission and CMB anisotropy. The beam with sidelobe effect is also considered. Our deep learning model is built upon ResUNet, which combines image generation algorithm UNet with the state-of-the-art architecture of deep learning, ResNet. The principal component analysis (PCA) method is employed to preprocess data before feeding it to the ResUNet. We find that, in the case of low instrumental noise, our UNet can efficiently reconstruct the CO signal map with correct line power spectrum by removing the foregrounds and recovering PCA signal loss and beam effects. Our method also can be applied to other intensity mappings like neutral hydrogen 21cm surveys.

Systematic studies of the rotation rate of sunspot groups using white-light images yield controversial results on the variations of the rotation rate: sunspot groups were found to either accelerate or decelerate systematically. This disagreement might be related to shortcomings of the method used to probe the rotation rate of sunspot groups. In contrast to previous works, in this study we use magnetic field maps to analyse the variations of the rotation rate of active regions. We found that an active region may exhibit either acceleration or deceleration during the emergence while the rotation rate remains almost unchanged during decay. Hence, we suppose that there is no systematic geometrical inclination to the radial direction of the apex of the subsurface magnetic flux loop forming an active region. A thorough comparison of the rotation rate of unipolar and bi/multipolar active regions revealed no significant changes in the rotation rate of decaying active regions. In contrast to previous works, we presume the rotation rate to keep constant (within the expected uncertainties) during the evolution of an active region after emergence.

The extraplanar diffuse ionized gas (eDIG) represents the cool/warm ionized gas reservoir around galaxies. We present a spatial analysis of H$\alpha$ images of 22 nearby edge-on spiral galaxies from the CHANG-ES sample (the eDIG-CHANGES project), taken with the APO 3.5m telescope, in order to study their eDIG. We conduct an exponential fit to the vertical intensity profiles of the sample galaxies, of which 16 can be decomposed into a thin disk plus an extended thick disk component. The median value of the scale height (h) of the extended component is $1.13\pm 0.14$ kpc. We find a tight sublinear correlation between h and the SFR. Moreover, the offset of individual galaxies from the best-fit SFR-h relation shows significant anti-correlation with SFR_SD. This indicates that galaxies with more intense star formation tend to have disproportionately extended eDIG. Combined with data from the literature, we find that the correlations between the eDIG properties and the galaxies' properties extend to broader ranges. We further compare the vertical extension of the eDIG to multi-wavelength measurements of other CGM phases. We find the eDIG to be slightly more extended than the neutral gas (HI 21-cm line), indicating the existence of some extended ionizing sources. Most galaxies have an X-ray scale height smaller than the h, suggesting that the majority of the X-ray emission detected in shallow observations are actually from the thick disk. The h is comparable to the L-band radio continuum scale height, both slightly larger than that at higher frequencies (C-band), where the cooling is stronger and the thermal contribution may be larger. The comparable H$\alpha$ and L-band scale height indicates that the thermal and non-thermal electrons have similar spatial distributions. This further indicates that the thermal gas, the cosmics rays, and the magnetic field may be close to energy equipartition.

We obtained mid-infrared spectra of chondrules, matrix, CAIs and bulk material from primitive type 1-4 chondrites in order to compare them with the dust material in young, forming solar systems and around comets. Our aim is to investigate whether there are similarities between the first processed materials in our early Solar System and protoplanetary disks currently forming around other stars. Chondrule spectra can be divided into two groups. 1) Chondrules dominated by olivine features at 11.3 micron and 10.0 micron. 2) mesostasis rich chondrules that show main features at 10 micron. Bulk ordinary chondrites show similar features to both groups. Fine-grained matrix is divided into three groups. 1) phyllosilicate-rich with a main band at 10 micron, 2) olivine-rich with bands at 11.3 micron and 10 micron, 3) pyroxene rich. Impact shock processed matrix from Murchison (CM2) shows features from phyllosilicate-rich, amorphous and olivine rich material. Astronomical spectra are divided into four groups based on their spectral characteristics, amorphous (group 1), pyroxene rich (group 2), olivine rich (group 3) and complex (group 4). Group 2 is similar to enstatite-rich fine grained material like e.g. Kakangari (K3) matrix. Group 3 and 4 can be explained by a combination of varying concentrations of olivine and mesostasis rich chondrules and fine grained matrix, but also show very good agreement with shock processed material. Comparison of band ratios confirms the similarity with chondritic material e.g. for HD100546, while the inner disk of HD142527 show no sign of chondrule material. Comparison between spectra indicate a general similarity between primitive solar system materials and circumstellar dust and comets.

The long-term stability of the Solar System is an issue of significant scientific and philosophical interest. The mechanism most likely to lead to instability is Mercury's eccentricity being pumped up to a high enough value that Mercury is either scattered by or collides with Venus. Previously, only three five-billion-year $N$-body ensembles of the Solar System with thousands of simulations have been run to assess long-term stability. We generate two additional ensembles, each with 2750 members, and make them publicly available at https://archive.org/details/@dorianabbot. We find that accurate Mercury instability statistics can be obtained by (1) including only the Sun and the 8 planets, (2) using a simple Wisdom-Holman scheme without correctors, (3) using a basic representation of general relativity, and (4) using a time step of 3.16 days. By combining our Solar System ensembles with previous ensembles we form a 9,601-member ensemble of ensembles. In this ensemble of ensembles, the logarithm of the frequency of a Mercury instability event increases linearly with time between 1.3 and 5 Gyr, suggesting that a single mechanism is responsible for Mercury instabilities in this time range and that this mechanism becomes more active as time progresses. Our work provides a robust estimate of Mercury instability statistics over the next five billion years, outlines methodologies that may be useful for exoplanet system investigations, and provides two large ensembles of publicly available Solar System integrations that can serve as testbeds for theoretical ideas as well as training sets for artificial intelligence schemes.

Short-period Galactic white dwarf binaries detectable by LISA are the only guaranteed persistent sources for multi-messenger gravitational-wave astronomy. Large-scale surveys in the 2020s present an opportunity to conduct preparatory science campaigns to maximize the science yield from future multi-messenger targets. The Nancy Grace Roman Space Telescope Galactic Bulge Time Domain Survey will (in its Reference Survey design) image seven fields in the Galactic Bulge approximately 40,000 times each. Although the Reference Survey cadence is optimized for detecting exoplanets via microlensing, it is also capable of detecting short-period white dwarf binaries. In this paper, we present forecasts for the number of detached short-period binaries the Roman Galactic Bulge Time Domain Survey will discover and the implications for the design of electromagnetic surveys. Although population models are highly uncertain, we find a high probability that the baseline survey will detect of order ~5 detached white dwarf binaries. The Reference Survey would also have a $\gtrsim20\%$ chance of detecting several known benchmark white dwarf binaries at the distance of the Galactic Bulge.

In Vilenkin's tunneling wavefunction proposal our expanding universe is born via a tunneling through a barrier from nothing at the zero scale factor. We explore the viability of this proposal for the spatially closed FLRW model with a positive cosmological constant including quantum gravity modifications in the Planck regime. Our setting is the effective spacetime description of loop quantum cosmology (LQC) which is known to replace the big bang singularity with a bounce due to the holonomy modifications. Due to the bounce, the barrier potential of the Wheeler-DeWitt theory is replaced by a step like potential which makes the tunneling proposal incompatible. But for a complete picture of singularity resolution, inverse scale factor modifications from quantum geometry must be included which play an important role at very small scale factors in the spatially closed models. We show that with inclusion of inverse scale factor modifications the resulting potential is again a barrier potential. The universe at the vanishing scale factor is dynamically non-singular and in an Einstein static like phase. We show that quantum geometric effects in LQC provide a non-singular completion of Vilenkin's tunneling proposal. We also find that quantum geometric effects result in a possibility of a tunneling to a quantum cyclic universe albeit for a very large value of cosmological constant determined by the quantum geometry.

Hidden symmetries provide a powerful tool for finding exact solutions in multifield cosmological models. We review how, using such symmetries, one can find inflationary solutions in two-field models, which lead to the generation of primordial black holes. We also discuss an exact solution in a two-field cosmological model, which describes dark energy. This solution is obtained with the use of a hidden symmetry, although the latter is broken by a constant term in the scalar potential. All of the above solutions are characterized by field-space trajectories with rapid turns.

We study the prospect to detect the cosmic background of sterile neutrinos in the Tritium $\beta$-decay, such as PTOLEMY-like experiments. The sterile neutrino with mass between 1 eV - 10 keV may contribute to the local density as warm or cold DM component. In this study, we investigate the possibility for searching them in the models with different production in the early Universe, without assuming sterile neutrino as full dark matter component. In these models, especially with low-reheating temperature or phase transition, the capture rate per year can be greatly enhanced to be $\mathcal O(10)$ without violating other astrophysical and cosmological observations.

With the advent of gravitational-wave astronomy and the discovery of more compact binary coalescences, data quality improvement techniques are desired to handle the complex and overwhelming noise in gravitational wave (GW) observational data. Though recent studies have shown promising results for data denoising, they are unable to precisely recover both the GW signal amplitude and phase. To address such an issue, we develop a deep neural network centered workflow, WaveFormer, for significant noise suppression and signal recovery on observational data from the Laser Interferometer Gravitational-Wave Observatory (LIGO). The WaveFormer has a science-driven architecture design with hierarchical feature extraction across a broad frequency spectrum. As a result, the overall noise and glitch are decreased by more than 1 order of magnitude and the signal recovery error is roughly 1% and 7% for the phase and amplitude, respectively. Moreover, we achieve state-of-the-art accuracy on reported binary black hole events of existing LIGO observing runs and substantial 1386 years inverse false alarm rate improvement on average. Our work highlights the potential of large neural networks for GW data quality improvement and can be extended to the data processing analyses of upcoming observing runs.

There has been increasing interest in investigating the possible parity violating features in the gravity theory and on the cosmological scales. In this work, we consider a class of scalar-nonmetricity theory, of which the Lagrangian is polynomial built of the nonmetricity tensor and a scalar field. The nonmetricity tensor is coupled with the scalar field through its first order derivative. Besides the monomials that are quadratic order in the nonmetricity tensor, we also construct monomials that are cubic order in the nonmetricity tensor in both the parity preserving and violating cases. These monomials act as the non-canonical (i.e., non-quadratic) kinetic terms for the spacetime metric, and will change the behavior in the propagation of the gravitational waves. We find that the gravitational waves are generally polarized, which present both the amplitude and velocity birefringence features due to the parity violation of the theory. Due to the term proportional to $1/k$ in the phase velocities, one of the two polarization modes suffers from the gradient instability on large scales.

We aim to explain the paradigm of a learning model, as well as to validate it in an applied case of an astronomy problem where the data used are declination, parallax, radial velocity of a star, as well as its annual variation in right ascension and declination. This study is based on a socio critical and positivist paradigm in the context of basic and applied science; algorithms and astronomical models were used as an instrument, which allowed us to address a specific case such as the calculation of the velocity of a star relative to the Sun.

For the stochastic gravitational wave backgrounds (SGWBs) search centred at the milli-Hz band, the galactic foreground produced by white dwarf binaries (WDBs) within the Milky Way contaminates the extra-galactic signal severely. Because of the anisotropic distribution pattern of the WDBs and the motion of the spaceborne gravitational wave interferometer constellation, the time-domain data stream will show an annual modulation. This property is fundamentally different from those of the SGWBs. In this Letter, we propose a new filtering method for the data vector based on the annual modulation phenomenon. We apply the resulted inverse variance filter to the LISA data challenge. The result shows that for the weaker SGWB signal, such as energy density $\Omega_{\rm astro}=5\times10^{-12}$, the filtering method can enhance the posterior distribution peak prominently. For the stronger signal, such as $\Omega_{\rm astro}=15\times10^{-12}$, the method can improve the Bayesian evidence from `substantial' to `strong' against null hypotheses. This method is model-independent and self-contained. It does not ask for other types of information besides the gravitational wave data.

In this paper, we study the quantum geometric effects near the locations that black hole horizons used to appear in the classical theory within the framework of the improved dynamic approach, in which the two polymerization parameters of the Kantowski-Sachs spacetime are functions of the phase variables. Our detailed analysis shows that the effects are so strong that black hole horizons of the effective quantum theory do not exist any longer, and the corresponding Kantowski-Sachs model now describes the entire spacetime of the trapped region, instead of being only the internal region of a black hole, as it is usually expected in loop quantum gravity.

The $f(R)$ Modified Gravity is a modification of Einstein's general theory of relativity, which aims to explain issues beyond The Standard Model of Cosmology such as dark energy and dark matter. As a theory of gravitation that govern major dynamics on the large scale of the universe, an $ f(R)$ model should be able to explain the transition from a matter-dominated universe to a dark-energy-dominated universe. Assuming that the density parameter of the radiation can be neglected during the transition from a matter-dominated universe to a dark-energy-dominated universe, we find some fixed points regarding the dynamical stability of the density parameters of the model. The phase transition can be achieved if the $f(R)$ model can connect the fixed point $P_5$ (representing the matter-dominated era) to the fixed point $P_1$ (representing the dark energy-dominated era). The method to evaluate that state transition is called the Fixed-point analysis. In this study, we analyze the viability of $f(R)$ models proposed by Starobinsky, Hu-Sawicki, and Gogoi-Goswami regarding the phase transition from a matter-dominated universe to a dark-energy-dominated universe. It is shown that those models are viable by choosing some set of appropriate parameters. For example, in the Starobinsky and Hu-Sawicki models, the parameter $\mu$ can be chosen to correspond to the lower bound of $x_d= R_1/Rc$, where $R_1$ represents the de-Sitter point. Meanwhile, for the Gogoi-Guswami model, the same results can be achieved by taking $\alpha$ and $\beta$ parameters satisfying the existence and stability conditions for the de-Sitter point. From these results, it can be concluded that those $f(R)$ models allow such phase transitions of the universe to realize the late-time accelerated expansion.

Once detected, lensed gravitational waves will afford new means to probe the matter distribution in the universe, complementary to electromagnetic signals. Sources of continuous gravitational waves (CWs) are long-lived and stable, making their lensing signatures synergic to short mergers of compact binaries. CWs emitted by isolated neutron stars and lensed by Sgr A$^*$, the super-massive black hole at the center of our galaxy, might be observable by the next generation of gravitational wave detectors. However, it is unknown under which circumstances these sources can be identified as lensed. Here we show that future detectors can distinguish lensed CWs and measure all parameters with precision $\sim 1-10\%$ for sources within $2-4$ Einstein radii of Sgr A$^*$, depending on the source's distance. Such a detection, which relies on the relative motion of the observer-lens-source system, can be observed for transverse velocities above 3 km/s. Therefore, the chances of observing strongly lensed neutron stars increase by one order of magnitude with respect to previous estimates. Observing strongly lensed CWs will enable novel probes of the galactic center and fundamental physics.

Microscopic theory of the nuclear response based on the relativistic meson-nucleon Lagrangian is applied to the description of the isoscalar giant monopole resonance (ISGMR) in a variety of nuclear systems. It is shown that the inclusion of beyond-mean-field correlations of the quasiparticle-vibration coupling (qPVC) type in the leading approximation allows for a simultaneous realistic description of the ISGMR in nuclei of led, tin and nickel mass regions, which is difficult on the mean-field level. The calculations are based on the NL3* parametrization of the relativistic finite-range meson-nucleon Lagrangian, which, in combination with the qPVC, have consistently demonstrated the ability to reliably describe many other nuclear structure phenomena. Systematic ISGMR calculations for nickel isotopes help reveal the central role of its coupling to the low-energy quadrupole states in the placement of the ISGMR centroids.

We study gravitational collapse for the Starobinsky $R^2$ model, a particular example of an $f(r)$ theory, in a spherically symmetric spacetime. We add a massless scalar field as matter content to the spacetime. We work in the Einstein frame, where an additional scalar field arises due to the conformal transformation. As in general relativity, depending on the initial data, we found that the gravity scalar field and the physical scalar field can collapse, forming a black hole, in which the final solution is the Schwarzschild metric. We found the threshold of black hole formation through a fine-tuning method and studied critical collapse near this regime.

Theory of gravity with a quadratic contribution of scalar curvature is investigated in terms of dynamical system approach. The simplest Friedmann-Robertson-Walker metric is used to formulate dynamics in Jordan frame as well as in conformally transformed Einstein frame. We show that in both frames there are stable de Sitter states for which the Hubble function expansion naturally gives terms corresponding to non-substantial dark matter. Using invariant centre manifold we show that in the Einstein frame there is a zero measure set of initial conditions leading from unstable to stable de Sitter state. Additionally, the initial de Sitter state is plunged with a parallelly propagated singularity. We show that the Jordan frame and the Einstein frame formulation of the theory are physically nonequivalent.

The effective cold quark matter model by Alford, Braby, Paris and Reddy (ABPR) is used as a tool for discussing the effect of the size of the pairing gap in three-flavor (CFL) quark matter on the maximum mass of hybrid neutron stars (NSs). This equation of state (EOS) has three parameters which we suggest to determine by comparison with a nonlocal NJL model of quark matter in the nonperturbative domain. We show that due to the momentum dependence of the pairing which is induced by the nonlocality of the interaction, the effective gap parameter in the EOS model is well approximated by a constant value depending on the diquark coupling strength in the NJL model Lagrangian. For the parameter $a_4=1-2\alpha_s/\pi$ a constant value below about \num{0.4} is needed to explain hybrid stars with ${\rm M}_{\rm max} \gtrsim 2.0~{\rm M}_\odot$, which would translate to an effective constant $\alpha_s\sim 1$. The matching point with a running coupling at the 1-loop $\beta$ function level is found to lie outside the range of chemical potentials accessible in NS interiors. A dictionary is provided for translating the free vector meson and diquark coupling parameters of the nlNJL model to those of the ABPR model that is equivalent in the nonperturbative domain but allows to quantify the transition to the asymptotic behaviour that is in accordance with perturbative QCD. We provide constraints on parameter sets that fulfill the $2~{\rm M}_\odot$ mass constraint for hybrid NSs, as well as the low tidal deformability constraint from GW170817 by a softening of the EOS on the hybrid NS branch with an early onset of deconfinement at ${\rm M}_{\rm onset}<1.4~{\rm M}_\odot$.

We propose a new non-trivial way to combine mimetic dark matter with the mimetic formulation of unimodular gravity. This yields a Weyl-invariant higher-derivative scalar-vector-tensor theory. We demonstrate that on-shell its behavior mimics GR with an additional k-essence scalar. The overall scale of the k-essence arises as an integration constant -- a global degree of freedom. Interestingly, we find that the resulting fluid cannot make transition through ultra-relativistic equation of state. We develop a method to find a mimetic theory corresponding to any eligible k-essence and identify, which k-essences can or cannot be reproduced this way. Finally, we show that abandoning the Weyl symmetry of the setup allows us to obtain both unimodular gravity and mimetic dark matter simultaneously, from one conformal redefinition of the metric.