Papers for Thursday, Jun 30 2022

We present a study of the intra-cluster population of low-mass X-ray binaries (LMXB) residing in globular clusters (GC) in the central 1 $deg^2$ of the Fornax galaxy cluster. Differently from previous studies, which were restricted to the innermost regions of individual galaxies, this work is aimed at comparing the properties of the intra-cluster population of GC-LMXBs with those of the host galaxy. We use VLT Survey Telescope (VST) and Chandra observations. We identify 168 LMXBs residing in GCs and divide it into host-galaxy and intra-cluster objects based on their distance from the nearest galaxy in terms of effective radius. We found 82 intra-cluster GC-LMXBs and 86 objects that are hosted in galaxies. We perform a Gaussian mixture model to divide the population into red and blue GCs. As has been found for the innermost regions of galaxies, LMXBs tend to form in red and bright GCs in intra-cluster space as well. We find, however, that the likelihood of a red GC to host an LMXB decreases with galactocentric distance, but it remains approximately constant for the blue GC population. Investigating the X-ray properties of the LMXBs residing in GCs, we find a difference in the X-ray luminosity function between the intra-cluster and host-galaxy sample: both follow a power-law down to $\sim 8.5\times 10^{37}$ erg s$^{-1}$, which is consistent with field LMXBs for the intra-cluster sample, while the latter agree with previous estimates for LMXBs in GCs. We detect a tentative difference in the hardness ratio of two populations, where the intra-cluster GC-LMXBs appear to have harder spectra than the host-galaxy objects. We find the same trend when we compare red and blue GC-LMXBs: the spectra of the blue sample are harder spectra than those of the red sample. This result could suggest a relation between the spectral properties of LMXBs and the host GC colour and therefore its metallicity.

We develop a set of machine-learning based cosmological emulators, to obtain fast model predictions for the $C(\ell)$ angular power spectrum coefficients characterising tomographic observations of galaxy clustering and weak gravitational lensing from multi-band photometric surveys (and their cross-correlation). A set of neural networks are trained to map cosmological parameters into the coefficients, achieving a speed-up $\mathcal{O}(10^3)$ in computing the required statistics for a given set of cosmological parameters, with respect to standard Boltzmann solvers, with an accuracy better than $0.175\%$ ($<0.1\%$ for the weak lensing case). This corresponds to $\sim 2\%$ or less of the statistical error bars expected from a typical Stage IV photometric surveys. Such overall improvement in speed and accuracy is obtained through ($\textit{i}$) a specific pre-processing optimisation, ahead of the training phase, and ($\textit{ii}$) a more effective neural network architecture, compared to previous implementations.

Brightest cluster galaxies (BCGs) are very massive elliptical galaxies found at the centers of clusters. Their study gives clues on the formation and evolution of the clusters in which they are embedded. We analysed here in a homogeneous way the properties of a sample of more than one thousand BCGs in the redshift range 0.15 < z < 0.7, based on images from the Canada France Hawaii Telescope Legacy Survey. Based on the cluster catalogue of 1371 clusters by Sarron et al. (2018), we applied our automatic BCG detection algorithm and identified successfully 70% of the BCGs in our sample. We analysed their 2D photometric properties with GALFIT. We also compared the position angles of the BCG major axes with those of the overall cluster to which they belong. We found no evolution of the BCG properties with redshift up to z = 0.7, in agreement with previous results by Chu et al. (2021), who analysed an order of magnitude smaller sample, but reaching a redshift z = 1.8. The Kormendy relation for BCGs is tight and consistent with that of normal elliptical galaxies and BCGs measured by other authors. The position angles of the BCGs and of the cluster to which they belong agree within 30 degrees for 55% of the objects with well defined position angles. The study of this very large sample of more than one thousand BCGs shows that they were mainly formed before z = 0.7, as we find no significant growth for the luminosities and sizes of central galaxies. We discuss the importance of the intracluster light in the interpretation of these results. We highlight the role of image depth in the modelisation of the luminosity profiles of BCGs, and give evidence for the presence of an inner structure which can only be resolved on deep surveys with limiting apparent magnitude at 80% completeness m80 > 26 mag/arcsec2.

The Euclid space telescope will survey a large dataset of cosmic voids traced by dense samples of galaxies. In this work we estimate its expected performance when exploiting angular photometric void clustering, galaxy weak lensing and their cross-correlation. To this aim, we implement a Fisher matrix approach tailored for voids from the Euclid photometric dataset and present the first forecasts on cosmological parameters that include the void-lensing correlation. We examine two different probe settings, pessimistic and optimistic, both for void clustering and galaxy lensing. We carry out forecast analyses in four model cosmologies, accounting for a varying total neutrino mass, $M_\nu$, and a dynamical dark energy (DE) equation of state, $w(z)$, described by the CPL parametrisation. We find that void clustering constraints on $h$ and $\Omega_b$ are competitive with galaxy lensing alone, while errors on $n_s$ decrease thanks to the orthogonality of the two probes in the 2D-projected parameter space. We also note that, as a whole, the inclusion of the void-lensing cross-correlation signal improves parameter constraints by $10-15\%$, and enhances the joint void clustering and galaxy lensing Figure of Merit (FoM) by $10\%$ and $25\%$, in the pessimistic and optimistic scenarios, respectively. Finally, when further combining with the spectroscopic galaxy clustering, assumed as an independent probe, we find that, in the most competitive case, the FoM increases by a factor of 4 with respect to the combination of weak lensing and spectroscopic galaxy clustering taken as independent probes. The forecasts presented in this work show that photometric void-clustering and its cross-correlation with galaxy lensing deserve to be exploited in the data analysis of the Euclid galaxy survey and promise to improve its constraining power, especially on $h$, $\Omega_b$, the neutrino mass, and the DE evolution.

CoRoT-7 is an active star, whose orbiting planets and their masses have been under debate since their initial detection. In the previous studies, CoRoT-7 was found to have two planets, CoRoT-7b and CoRoT-7c with orbital periods of 0.85 and 3.69 days, and a potential third planet with a period of $\sim$9 days. The existence of the third planet has been questioned as potentially being an activity-induced artefact. Mass of the transiting planet CoRoT-7b has been estimated to have widely different values owing to the activity level of the parent star, the consequent Radial Velocity (RV) 'jitter', and the methods used to rectify this ambiguity. Here we present an analysis of the HARPS archival RV data of CoRoT-7 using a new wavelength-domain technique, scalpels, to correct for the stellar activity-induced spectral line-shape changes. Simultaneous modelling of stellar activity and orbital motions, identified using the l1- periodogram, shows that scalpels effectively reduce the contribution of stellar variability to the RV signal and enhance the detectability of exoplanets around active stars. Using kima nested-sampling package, we modelled the system incorporating a Gaussian Process together with scalpels. The resultant posterior distributions favoured a three-planet system comprising two non-transiting planets, CoRoT-7c and CoRoT-7d with orbital periods of 3.697$\pm$0.005 and 8.966$\pm$1.546 days, in addition to the known transiting planet. The transiting planet CoRoT-7b is found to be a rocky super-Earth with a mass of $M_{b}$=6.06$\pm$0.65 $M_{\oplus}$. The determined masses of $M_{c}$=13.29$\pm$0.69 $M_{\oplus}$ and $M_{d}$=17.14$\pm$2.55 $M_{\oplus}$ suggest the non-transiting planets CoRoT-7c and CoRoT-7d to be structurally similar to Uranus and Neptune.

We report and analyse the presence of foregrounds in the cosmic microwave background (CMB) radiation associated to extended galactic halos. Using the cross correlation of Planck and WMAP maps and the 2MRS galaxy catalogue, we find that the mean temperature radial profiles around nearby galaxies at $cz\le 4500~\rm{km~s^{-1}}$ show a statistically significant systematic decrease of $\sim 15~\mu \rm{K}$ extending up to several galaxy radii. This effect strongly depends on the galaxy morphological type at scales within several tens of times the galaxy size, becoming nearly independent of galaxy morphology at larger scales. The effect is significantly stronger for the more extended galaxies, with galaxy clustering having a large impact on the results. Our findings indicate the presence of statistically relevant foregrounds in the CMB maps that should be considered in detailed cosmological studies. Besides, we argue that these can be used to explore the intergalactic medium surrounding bright late-type galaxies and allow for diverse astrophysical analyses.

The intrinsic alignment (IA) of galaxies is potentially a major limitation in deriving cosmological constraints from weak lensing surveys. In order to investigate this effect we assign intrinsic shapes and orientations to galaxies in the light-cone output of the MICE simulation, spanning $\sim5000\,{\rm deg}^2$ and reaching redshift $z=1.4$. This assignment is based on a 'semi-analytic' IA model that uses photometric properties of galaxies as well as the spin and shape of their host halos. Advancing on previous work, we include more realistic distributions of galaxy shapes and a luminosity dependent galaxy-halo alignment. The IA model parameters are calibrated against COSMOS and BOSS LOWZ observations. The null detection of IA in observations of blue galaxies is accounted for by setting random orientations for these objects. We compare the two-point alignment statistics measured in the simulation against predictions from the analytical IA models NLA and TATT over a wide range of scales, redshifts and luminosities for red and blue galaxies separately. We find that both models fit the measurements well at scales above $8\,h^{-1}{\rm Mpc}$, while TATT outperforms NLA at smaller scales. The IA parameters derived from our fits are in broad agreement with various observational constraints from red galaxies. Lastly, we build a realistic source sample, mimicking DES Year 3 observations and use it to predict the IA contamination to the observed shear statistics. We find this prediction to be within the measurement uncertainty, which might be a consequence of the random alignment of blue galaxies in the simulation.

The Astropy Project supports and fosters the development of open-source and openly-developed Python packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core package $\texttt{astropy}$, which serves as the foundation for more specialized projects and packages. In this article, we summarize key features in the core package as of the recent major release, version 5.0, and provide major updates for the Project. We then discuss supporting a broader ecosystem of interoperable packages, including connections with several astronomical observatories and missions. We also revisit the future outlook of the Astropy Project and the current status of Learn Astropy. We conclude by raising and discussing the current and future challenges facing the Project.

U Sco is a recurrent nova with eleven observed eruptions, most recently in 2010.1 and 2022.4. I report on my program (running since 1989) of measuring eclipse times and brightnesses of U Sco in quiescence, from 2010 to 2022. The orbital period suddenly increased by +22.4 +- 1.0 parts-per-million across the 2010.1 eruption. This period change is greater than the near-zero period change (+3.9 +- 6.1 parts-per-million) across the 1999.2 eruption. This period change cannot come from any of the usual mechanisms, whereas the one remaining possibility is that the period changes are dominated by the little-known mechanism of the nova ejecting asymmetric shells. From 2010.1 to 2016.78, the O-C curve showed a steady period change that was large, with P-dot equal (-21.0 +- 3.2)X 10^-9. This is greatly higher than the steady period changes in the two previous inter-eruption intervals (-3.2 +- 1.9 and -1.1 +- 1.1 X 10^-9). This large, variable, and negative P-dot apparently comes from magnetic braking of the companion star's rotation. Starting in 2016.9 +- 0.6, the O-C curve showed a strong kink that is a unique characteristic of the sudden period change (+35.4 +- 7.1 parts-per-million) across a nova event. The brightness in quiescence after 2010.4 shows that the white dwarf accreted the trigger mass for the next nova event in the year 2017.1 +- 0.6. Photometric records show the only possible time for the eruption to peak (such that its total duration of 60 days was undetectable by any observation) is during a 75 day interval inside the 2016 solar gap, thus constraining the missed eruption to 2016.78 +- 0.10.

The discovery in deep near-infrared surveys of a population of massive quiescent galaxies at $z>3$ has given rise to the question of how they came to be quenched so early in the history of the Universe. Measuring their molecular gas properties can distinguish between physical processes where they stop forming stars due to a lack of fuel versus those where star-formation efficiency is reduced and the gas is retained. We conducted Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of four quiescent galaxies at $z=$ 3.5-4.0 found by the Fourstar Galaxy Evolution Survey (ZFOURGE) and a serendipitous optically dark galaxy at $z=3.71$. We aim to investigate the presence of dust-obscured star-formation and their gas content by observing the dust continuum emission at Band-7 and the atomic carbon [C I]($^3P_1$-$^3P_0$) line at 492.16 GHz. Among the four quiescent galaxies, only one source is detected in the dust continuum at $\lambda_{\rm obs} = 870 {\rm \mu m}$. The sub-mm observations confirm their passive nature, and all of them are located more than four times below the main sequence of star-forming galaxies at $z=3.7$. None of the targets are detected in [C I], constraining their gas mass fractions to be $<$ 20%. These gas mass fractions are more than three times lower than the scaling relation for star-forming galaxies at $z=3.7$. These results support scenarios where massive galaxies at $z=$ 3.5-4.0 quench by consuming/expelling all the gas rather than by reducing the efficiency of the conversion of their gas into stars.

The architecture and evolution of planetary systems are shaped in part by stellar flybys. Within this context, we look at stellar encounters which are too weak to immediately destabilize a planetary system but are nevertheless strong enough to measurably perturb the system's dynamical state. We estimate the strength of such perturbations on secularly evolving systems using a simple analytic model and confirm those estimates with direct N-body simulations. We then run long-term integrations and show that even small perturbations from stellar flybys can influence the stability of planetary systems over their lifetime. We find that small perturbations to the outer planets' orbits are transferred between planets, increasing the likelihood that the inner planetary system will destabilize. Specifically, our results for the Solar System show that relative perturbations to Neptune's semi-major axis of order 0.1% are strong enough to increase the probability of destabilizing the Solar System within 5 Gyrs by one order of magnitude.

A global instability is shown to be unstable to non-axisymmetric perturbations in a differentially rotating Keplerian disk containing either vertical or azimuthal magnetic fields. In an unstratified cylindrical disk model, using both global eigenvalue stability analysis and linear global initial-value simulations, it is demonstrated that this instability dominates at strong magnetic field where local standard MRI becomes stable. Unlike the standard MRI mode, which is concentrated in the high flow shear region, these distinct global modes (with low azimuthal mode numbers) are extended in the global domain and receive their free energy from the Alfv\'en continua. As its mode structure and relative dominance over MRI is inherently determined by the global spatial curvature as well as the flow shear in the presence of magnetic field, we call it the magneto-curvature (magneto-spatial-curvature) instability. Consistent with the linear analysis, as the field strength is increased in the nonlinear simulations, a transition from a MRI-driven turbulence to a state dominated by global non-axisymmetric modes is obtained. This global instability could therefore be a source of nonlinear transport in accretion disks at higher magnetic field than predicted by local models.

An Integral Field Unit (IFU) based on image-slicers has been added to the GREGOR Infrared Spectrograph (GRIS). This upgrade to the instrument makes possible 2D spectropolarimetry in the near-infrared by simultaneously recording the full Stokes profiles of spectral lines (in a given spectral interval) at all the points in the field of view. It provides high-cadence spectropolarimetric observations at the instrument's high spatial resolution and high polarization sensitivity at the GREGOR solar telescope. The IFU is ideal for observing the polarized spectrum of fast-evolving solar features at high spatial and spectral resolutions. The high observing cadence opens the possibility of time-series observations. The analysis of observations to this level of accuracy is essential for understanding the complex dynamics and interactions of solar plasma and magnetic fields. The image slicer of the IFU has eight slices of width 100 micron, covering a total field of view of 6" x 3". It was designed and built within the framework of the European projects SOLARNET and GREST, as a prototype for future instruments of the European Solar Telescope (EST) and was integrated into GRIS. After two commissioning campaigns in 2017 and 2018, the IFU was finally installed at the end of September 2018 and offered to all observers who use the telescope.

We present optimal survey strategies for the upcoming NIX imager, part of the ERIS instrument to be installed on the Very Large Telescope (VLT). We will use a custom 2.2 micron K-peak filter to optimise the efficiency of a future large-scale direct imaging survey, aiming to detect brown dwarfs and giant planets around nearby stars. We use the results of previous large scale imaging surveys (primarily SPHERE SHINE and Gemini GPIES) to inform our choice of targets, as well as improved planet population distributions. We present four possible approaches to optimise survey target lists for the highest yield of detections: i) targeting objects with anomalous proper motion trends, ii) a follow-up survey of dense fields from SPHERE SHINE and Gemini GPIES iii) surveying nearby star-forming regions and iv) targeting newly discovered members of nearby young moving groups. We also compare the predicted performance of NIX to other state-of-the-art direct imaging instruments.

We present late-time radio/millimeter (as well as optical/UV and X-ray) detections of the tidal disruption event (TDE) AT2018hyz, spanning $970 - 1300$ d after optical discovery. In conjunction with earlier deeper limits, including at $\approx 700$ d, our observations reveal rapidly rising emission at $0.8-240$ GHz, steeper than $F_\nu\propto t^5$ relative to the time of optical discovery. Such a steep rise cannot be explained in any reasonable scenario of an outflow launched at the time of disruption (e.g., off-axis jet, sudden increase in the ambient density), and instead points to a delayed launch. Our multi-frequency data allow us to directly determine the radius and energy of the radio-emitting outflow, showing that it was launched $\approx 750$ d after optical discovery. The outflow velocity is mildly relativistic, with $\beta\approx 0.25$ and $\approx 0.6$ for a spherical and a $10^\circ$ jet geometry, respectively, and the minimum kinetic energy is $E_K\approx 5.8\times 10^{49}$ and $\approx 6.3\times 10^{49}$ erg, respectively. This is the first definitive evidence for the production of a delayed mildly-relativistic outflow in a TDE; a comparison to the recently-published radio light curve of ASASSN-15oi suggests that the final re-brightening observed in that event (at a single frequency and time) may be due to a similar outflow with a comparable velocity and energy. Finally, we note that the energy and velocity of the delayed outflow in AT2018hyz are intermediate between those of past non-relativistic TDEs (e.g., ASASSN-14li, AT2019dsg) and the relativistic TDE Sw\,J1644+57. We suggest that such delayed outflows may be common in TDEs.

Between 2010 and 2017 we have collected new optical and radar observations of the potentially hazardous asteroid (2102)~Tantalus from the ESO NTT and Danish telescopes at the La Silla Observatory and from the Arecibo planetary radar. The object appears to be nearly spherical, showing a low amplitude light-curve variation and limited large-scale features in the radar images. The spin-state is difficult to constrain with the available data; including a certain light-curve subset significantly changes the spin-state estimates, and the uncertainties on period determination are significant. Constraining any change in rotation rate was not possible, despite decades of observations. The convex lightcurve-inversion model, with rotational pole at ${\lambda}=210{\pm}41${\deg} and ${\beta}=-30{\pm}35${\deg}, is more flattened than the two models reconstructed by including radar observations: with prograde (${\lambda}=36{\pm}23${\deg}, ${\beta}=30{\pm}15${\deg}), and with retrograde rotation mode (${\lambda}=180{\pm}24${\deg}, ${\beta}=-30{\pm}16${\deg}). Using data from WISE we were able to determine that the prograde model produces the best agreement in size determination between radar and thermophysical modelling. Radar measurements indicate possible variation in surface properties, suggesting one side might have lower radar albedo and be rougher at centimetre-to-decimetre scale than the other. However, further observations are needed to confirm this. Thermophysical analysis indicates a surface covered in fine-grained regolith, consistent with radar albedo and polarisation ratio measurements. Finally, geophysical investigation of the spin-stability of Tantalus shows that it could be exceeding its critical spin-rate via cohesive forces.

Gravitational lensing of fast radio bursts (FRBs) offers an exciting avenue for several cosmological applications. However, it is not yet clear how many such events future surveys will detect nor how to optimally find them. We use the known properties of FRBs to forecast detection rates of gravitational lensing on delay timescales from microseconds to years, corresponding to lens masses spanning fifteen orders of magnitude. We highlight the role of the FRB redshift distribution on our ability to observe gravitational lensing. We consider cosmological lensing of FRBs by stars in foreground galaxies and show that strong stellar lensing will dominate on microsecond timescales. Upcoming surveys such as DSA-2000 and CHORD will constrain the fraction of dark matter in compact objects (e.g. primordial black holes) and may detect millilensing events from intermediate mass black holes (IMBHs) or small dark matter halos. Coherent all-sky monitors will be able to detect longer-duration lensing events from massive galaxies, in addition to short time-scale lensing. Finally, we propose a new application of FRB gravitational lensing that will measure directly the circumgalactic medium of intervening galaxies.

Thin synchrotron-emitting filaments are increasingly seen in the intracluster medium (ICM). We present the first example of a direct interaction between a magnetic filament, a radio jet, and a dense ICM clump in the poor cluster Abell 194. This enables the first exploration of the dynamics and possible histories of magnetic fields and cosmic rays in such filaments. Our observations are from the MeerKAT Galaxy Cluster Legacy Survey and the LOFAR Two Metre Sky Survey. Prominent 220 kpc long filaments extend east of radio galaxy 3C40B, with very faint extensions to 300 kpc, and show signs of interaction with its northern jet. They curve around a bend in the jet and intersect the jet in Faraday depth space. The X-ray surface brightness drops across the filaments; this suggests that the relativistic particles and fields contribute significantly to the pressure balance and evacuate the thermal plasma in a $\sim$35 kpc cylinder. We explore whether the relativistic electrons could have streamed along the filaments from 3C40B, and present a plausible alternative whereby magnetized filaments are a) generated by shear motions in the large-scale, post-merger ICM flow, b) stretched by interactions with the jet and flows in the ICM, amplifying the embedded magnetic fields, and c) perfused by re-energized relativistic electrons through betatron-type acceleration or diffusion of turbulently accelerated ICM cosmic ray electrons. We use the Faraday depth measurements to reconstruct some of the 3D structures of the filaments and of 3C40A and B.

We report the discovery of an eccentric hot Neptune and a non-transiting outer planet around TOI-1272. We identified the eccentricity of the inner planet, with an orbital period of 3.3 d and $R_{\rm p,b} = 4.1 \pm 0.2$ $R_\oplus$, based on a mismatch between the observed transit duration and the expected duration for a circular orbit. Using ground-based radial velocity measurements from the HIRES instrument at the Keck Observatory, we measured the mass of TOI-1272b to be $M_{\rm p,b} = 25 \pm 2$ $M_\oplus$. We also confirmed a high eccentricity of $e_b = 0.34 \pm 0.06$, placing TOI-1272b among the most eccentric well-characterized sub-Jovians. We used these RV measurements to also identify a non-transiting outer companion on an 8.7-d orbit with a similar mass of $M_{\rm p,c}$ sin$i= 27 \pm 3$ $M_\oplus$ and $e_c \lesssim 0.35$. Dynamically stable planet-planet interactions have likely allowed TOI-1272b to avoid tidal eccentricity decay despite the short circularization timescale expected for a close-in eccentric Neptune. TOI-1272b also maintains an envelope mass fraction of $f_{\rm env} \approx 11\%$ despite its high equilibrium temperature, implying that it may currently be undergoing photoevaporation. This planet joins a small population of short-period Neptune-like planets within the "Hot Neptune Desert" with a poorly understood formation pathway.

Given the ever-increasing number of time-domain astronomical surveys, employing robust, interpretative, and automated data-driven classification schemes is pivotal. This work presents new data-driven classification heuristics for spectral data based on graph theory. As a case in point, we devise a spectral classification scheme of Type II supernova (SNe II) as a function of the phase relative to the $V$-band maximum light and the end of the plateau phase. We use compiled optical data sets comprising 145 SNe and 1595 optical spectra in 4000-9000 angstrom. Our classification method naturally identifies outliers and arranges the different SNe in terms of their major spectral features. We compare our approach to the off-the-shelf UMAP manifold learning and show that both strategies are consistent with a continuous variation of spectral types rather than discrete families. The automated classification naturally reflects the fast evolution of Type II SNe around the maximum light while showcasing their homogeneity close to the end of the plateau phase. The scheme we develop could be more widely applicable to unsupervised time series classification or characterisation of other functional data.

We propose the scenario to interpret the overall observational features of the SS433--W50 system. The most unique features of SS433 are the presence of the precessing, mildly relativistic jets and the obscuration of the central engine, which are considered to be due to a supercritical accretion on to the central compact object. The jets are likely to be ejected from the innermost region of the accretion flow. The concept of the accretion ring (Inoue 2021, PASJ, 73,795) is applied to the outer boundary of the accretion flow and the ring is supposed to have a precession. The accretion ring is expected to extend a two-layer outflow of a thin excretion disk and a thick excretion flow, as well as the accretion flow. The thin excretion disk is discussed to eventually form the optically thick excretion belt along the Roche lobe around the compact object, contributing to the obscuration of the central engine. The thick excretion flow is likely to turn to the supersonic wind (disk wind) with the terminal velocity of $\sim 10^{8}$ cm s$^{-1}$ and to collide with the SNR matter at the distance of $\sim 10^{18}$ cm. The interactions of the jets with the disk wind are considered to cause the features of the jets observed at the distances of 10$^{14} \sim 10^{15}$ cm and $\sim 10^{17}$ cm. Finally, it is discussed that the jets are braked by the SNR matter at the distance of $\sim$10 pc and the momentum carried by the jet is transferred to the SNR matter shoved by the jet. The SNR matter pushed to the inside of the precession cone is expected to gather along the cone axis and to form the elongated structures in the east and west directions from the main W50 structure.

We develop the power spectral density (PSD) model to explain the nature of the X-ray variability in IRAS 13224-3809, including the full effects of the X-ray reverberation due to the lamp-post source. We utilize 16 XMM-Newton observations individually as well as group them into three different luminosity bins: low, medium and high. The soft (0.3-1 keV) and hard (1.2-5 keV) PSD spectra are extracted and simultaneously fitted with the model. We find that the corona height changes from h ~ 3 $\ r_{\rm g}$ during the lowest luminosity state to ~ $25 \ r_{\rm g}$ during the highest luminosity state. This provides further evidence that the source height from the reverberation data is significantly larger than what constrained by the spectral analysis. Furthermore, as the corona height increases, the energy spectrum tends to be softer while the observed fractional excess variance, $F_{\rm var}$, reduces. We find that the PSD normalization is strongly correlated with $F_{\rm var}$, and moderately correlated with the PSD bending index. Therefore, the normalization is dependent on accretion rate that controls the intrinsic shape of the PSD. While the intrinsic variability of the disk is manifested by the reverberation signals, the disk and corona may evolve independently. Our results suggest that, during the source height increases, the disk itself generates less overall variability power but more high-frequency variability resulting in the PSD spectrum that flattens out (i.e. the inner disk becomes more active). Using the luminosity-bin data, the hint of Lorentzian component is seen, with the peak appearing at lower frequencies with increasing luminosity.

We present a scalable, cloud-based science platform solution designed to enable next-to-the-data analyses of terabyte-scale astronomical tabular datasets. The presented platform is built on Amazon Web Services (over Kubernetes and S3 abstraction layers), utilizes Apache Spark and the Astronomy eXtensions for Spark for parallel data analysis and manipulation, and provides the familiar JupyterHub web-accessible front-end for user access. We outline the architecture of the analysis platform, provide implementation details, rationale for (and against) technology choices, verify scalability through strong and weak scaling tests, and demonstrate usability through an example science analysis of data from the Zwicky Transient Facility's 1Bn+ light-curve catalog. Furthermore, we show how this system enables an end-user to iteratively build analyses (in Python) that transparently scale processing with no need for end-user interaction. The system is designed to be deployable by astronomers with moderate cloud engineering knowledge, or (ideally) IT groups. Over the past three years, it has been utilized to build science platforms for the DiRAC Institute, the ZTF partnership, the LSST Solar System Science Collaboration, the LSST Interdisciplinary Network for Collaboration and Computing, as well as for numerous short-term events (with over 100 simultaneous users). A live demo instance, the deployment scripts, source code, and cost calculators are accessible at this http URL

On January 15, 2022, at 04:14:45 (UTC), the undersea volcano of Hunga Tonga-Funga Ha'apai erupted, and global seismic waves, shock waves, and electromagnetic waves generated by the eruption in Tonga reached Japan, more than 8,000 km away. KAGRA is a gravitational wave telescope located in an underground facility in Kamioka, Japan. It has a wide variety of auxially sensors to monitor environmental disturbances which obstruct observation of gravitational waves. The effects of the volcanic eruption were observed by these environmental sensors both inside and outside of the underground facility. In particular, the shock waves made it possible to evaluate the transfer functions from the air-pressure wave in the atmosphere to the underground environmental disturbances (air-pressure and seismic motion).

Estimating the spin of SgrA$^*$ is one of the current challenges we face in understanding the center of our Galaxy. In the present work, we show that detecting the gravitational waves (GWs) emitted by a brown dwarf inspiraling around SgrA$^*$ will allow us to measure the mass and the spin of SgrA$^*$ with unprecedented accuracy. Such systems are known as extremely large mass-ratio inspirals (XMRIs) and are expected to be abundant and loud sources in our galactic center. We consider XMRIs with a fixed orbital inclination and two scenarios for SgrA$^*$'s spin ($s$): A highly spinning scenario where $s$=0.9 and a low spinning scenario where $s$=0.1. For both cases, we obtain the number of circular and eccentric XMRIs expected to be detected by space-borne GW detectors like LISA and TianQin. We later perform a Fisher matrix analysis to show that by detecting a single XMRI the mass of SgrA$^*$ can be determined with an accuracy ranging from 0.06 to 3 solar masses while the spin can be measured with an accuracy between 1.5$\times$10$^{-7}$ and 4$\times$10$^{-4}$.

We review the timing and spectral evolution of black hole X-ray binary systems, with emphasis on the current accretion-ejection paradigm. When in outburst, stellar mass black hole binaries may become the brightest X-ray sources in the sky. Analysis of high signal to noise data has resulted in a general framework of correlated X-ray spectral and fast timing behavior during an outburst. We utilize recent data from small but powerful observatories launched in the last decade supported by multi-wavelength ground-based observations. Coordinated observations showed that outflows (in the form of jets and winds) are an integral part of this evolution, providing a coherent phenomenological picture that we discuss in terms of the hardness-intensity diagram and spectral states. We pay particular attention to the evolution of broad and narrow emission and absorption lines and hard tails in the energy spectrum, quasi-periodic oscillations, lags and reverberation from fast timing studies, making the connections with multi-wavelength observations when relevant. We use the bright outburst of MAXI J1820+070 as a recent test case to discuss different aspects of spectral and timing evolution, but the data and results are not limited to this source. In the second part of the review, we discuss competing theoretical models that can explain different aspects of the rich phenomenology. Data from future missions and simulation results will have the power to resolve discrepancies in these models and black hole binary research will continue to be an exciting field that allows for tests of fundamental physics and studies of the properties of matter in strong gravitational fields.

A search for close encounters of stars with the Solar System was performed using data from the Gaia\,DR3 catalog. We considered 31 stars with the approach parameter $d_{\rm min}<1$~pc. Among them, 15 stars are appearing as candidates for close encounters for the first time. The status of the stars GJ\,710 and HD\,7977 has been confirmed as candidates for deep penetration into the inner region of the Oort cloud. In particular, for GJ\,710 and HD\,7977, respectively, the following estimates of approach parameters are obtained: $t_{\rm min}= 1.324\pm0.026$~Myr and $d_{\rm min}=0.018\pm0.002$~pc, $t_{\rm min}=-2.830\pm0.025$~Myr and $d_{\rm min}=0.071\pm0.027$~pc. Among the newly identified candidates, the most interesting is the white dwarf WD\,0810-353, for which the following approach parameters were found: $t_{\rm min}=0.029\pm0.001$~Myr and $d_{\rm min}=0.150\pm0.003$~pc.

Supermassive stars (SMSs) with masses of $M_\ast \simeq 10^4$--$10^5~{\rm M_\odot}$ are invoked as possible seeds of high-redshift supermassive black holes, but it remains under debate whether their protostar indeed acquires sufficient mass via gas accretion overcoming radiative feedback. We investigate protostellar growth in dynamically heated atomic-cooling haloes (ACHs) found in recent cosmological simulations, performing three-dimensional radiation hydrodynamical (RHD) simulations that consider stellar evolution under variable mass accretion. We find that one of the ACHs feeds the central protostar at rates exceeding a critical value, above which the star evolves in a cool bloating phase and hardly produces ionizing photons. Consequently, the stellar mass reaches $M_\ast \gtrsim 10^4~{\rm M_\odot}$ unimpeded by radiative feedback. In the other ACH, where the mass supply rate is lower, the star spends most of its life as a hot main-sequence star, emitting intense ionizing radiation. Then, the stellar mass growth is terminated around $500~{\rm M_\odot}$ by photoevaporation of the circumstellar disk. A series of our RHD simulations provide a formula of the final stellar mass determined either by stellar feedback or their lifetime as a function of the mass supply rate from the parent cloud in the absence of stellar radiation. Combining the results with the statistical properties of SMS-forming clouds in high-redshift quasar progenitor haloes, we construct a top-heavy mass distribution of primordial stars over $M_\ast \simeq 100$--$10^5~{\rm M_\odot}$, approximately following a power-law spectrum of $\propto M_\ast^{-1.3}$ with a steeper decline at $M_\ast \gtrsim 2 \times 10^4~{\rm M_\odot}$. Their massive BH remnants would be further fed via the dense debris disk, powering "milli-quasars" with a bolometric luminosity of $L_{\rm bol}~\gtrsim~10^{43}~{\rm erg~s^{-1}}$.

Since July 2014, the Gaia space mission has been continuously scanning the sky and observing the extragalactic Universe with unprecedented spatial resolution in the optical domain ($\sim$ 180 mas by the end of the mission). Gaia provides an opportunity to study the morphology of the galaxies of the local Universe (z<0.45) with much higher resolution than has ever been attained from the ground. It also allows us to provide the first morphological all-sky space catalogue of nearby galaxies and galaxies that host quasars in the visible spectrum. We present the Data Processing and Analysis Consortium CU4-Surface Brightness Profile fitting pipeline, which aims to recover the light profile of nearby galaxies and galaxies hosting quasars. The pipeline uses a direct model based on the Radon transform to measure the two-dimensional surface brightness profile of the extended sources. It simulates a large set of 2D light profiles and iteratively looks for the one that best reproduces the 1D observations by means of a Bayesian exploration of the parameters space. We also present our method for setting up the input lists of galaxies and quasars to be processed. We successfully analysed 1\,103\,691 known quasars and detected a host galaxy around 64\,498 of them ($\sim$6\%). We publish the surface brightness profiles of the host for a subset of 15\,867 quasars with robust solutions. The distribution of the S\'ersic index describing the light profile of the host galaxies peaks at $\sim$ 0.8 with a mean value of $\sim$ 1.9, indicating that these galaxies hosting a quasar are consistent with disc-like galaxies. The pipeline also analysed 940\,887 galaxies with both a \sersic and a de Vaucouleurs profile and derived robust solutions for 914\,837 of them. The distribution of the S\'ersic indices confirms that \gaia mostly detects elliptical galaxies and that very few discs are measured.

Core-collapse supernova remnants are the gaseous nebulae of galactic interstellar media (ISM) formed after the explosive death of massive stars. Their morphology and emission properties depend both on the surrounding circumstellar structure shaped by the stellar wind-ISM interaction of the progenitor star and on the local conditions of the ambient medium. In the warm phase of the Galactic plane (n = 1/cm3, T = 8000 K), an organised magnetic field of strength 7 microG has profound consequences on the morphology of the wind bubble of massive stars at rest. In this paper we show through 2.5D magneto-hydrodynamical simulations, in the context of a Wolf-Rayet-evolving 35 Mo star, that it affects the development of its supernova remnant. When the supernova remnant reaches its middle age (15 to 20 kyr), it adopts a tubular shape that results from the interaction between the isotropic supernova ejecta and the anisotropic, magnetised, shocked stellar progenitor bubble into which the supernova blast wave expands. Our calculations for non-thermal emission, i.e. radio synchrotron and inverse Compton radiation, reveal that such supernova remnants can, due to projection effects, appear as rectangular objects in certain cases. This mechanism for shaping a supernova remnant is similar to the bipolar and elliptical planetary nebula production by wind-wind interaction in the low-mass regime of stellar evolution. If such a rectangular core-collapse supernova remnant is created, the progenitor star must not have been a runaway star. We propose that such a mechanism is at work in the shaping of the asymmetric core-collapse supernova remnant Puppis A.

The measurement of the individual charged particles especially muons in an extended air shower (EAS) resulting from primary cosmic rays provides important distinguishing parameters to identify the chemical composition of the cosmic primary particles. For Neutrino Telescope experiments like Baikal-GVD, the estimation of underwater muon flux is of importance to study atmospheric muons. In this paper, a GEANT4-based simulation is presented to estimate the atmospheric muon flux underwater taking Baikal-GVD as an example. The location of the Baikal-GVD experiment at Lake Baikal provides a unique opportunity to study the passage of muons through its northern shore and the water. The muons arriving from the north direction will lose more energy as compared to those arriving from the south. An approximation for the northern shore is also simulated in the GEANT4 geometry and the results of the simulation are compared with the measurements from the NT-96 detector. The results of the simulations are consistent with the shore shadow observed in the measurements in the NT-96. This approach can also be used to propagate the muons from generators like CORSIKA through long distances in matter like water, ice, earth, etc. for simulations in such experiments.

The accretion rates needed to fuel the central black hole in a galaxy can be achieved via viscous torques in thick disks and rings, which can be resolved by millimetre interferometry within the inner ~20pc of the active galaxy NGC1068 at comparable scales and sensitivity to single dish observations of the Circumnuclear Disk (CND) in the Galactic Center. To interpret observations of these regions and determine the physical properties of their gas distribution, we present a modelling effort that includes (i) a simple dynamical simulations involving partially inelastic collisions between disk gas clouds, (ii) an analytical model of a turbulent clumpy gas disk calibrated by the dynamical model and observations, (iii) local turbulent and cosmic ray gas heating and cooling via H2O, H2, and CO emission, and (iv) determination of the molecular abundances. We also consider photodissociation regions (PDR) where gas is directly illuminated by the central engine. We compare the resulting model datacubes of the CO, HCN, HCO+, and CS brightness temperatures to available observations. In both cases the kinematics can be explained by one or two clouds colliding with a pre-existing ring, in a prograde sense for the CND and retrograde for NGC1068. And, with only dense disk clouds, the line fluxes can be reproduced to within a factor of about two. To avoid self-absorption of the intercloud medium, turbulent heating at the largest scales, comparable to the disk height, has to be decreased by a factor of 50-200. Our models indicate that turbulent mechanical energy input is the dominant gas heating mechanism within the thick gas disks. In N1068, while the bulk of the AGN X-ray radiation is absorbed in a layer of Compton-thick gas inside the dust sublimation radius, the optical/UV radiation may enhance the molecular line emission from photodissociation regions by ~50% at the inner edge of the gas ring.

Neutron stars are known to show accelerated spin-up of their rotational frequency called a glitch. A glitch in an isolated neutron star can excite the fundamental (\textit{f})-mode oscillations which can lead to gravitational wave generation. This gravitational wave signal associated with stellar fluid oscillations has a damping time of a few seconds and occurs at the frequency range between $1.5 -3$\,kHz, which is within the detectable range of the current generation of ground-based detectors. Electromagnetic observations of pulsars (and hence pulsar glitches) require the pulsar to be oriented so that the jet is pointed towards the detector, but this is not a requirement for gravitational wave emission which is more isotropic and not jet-like. Hence, gravitational wave observations have the potential to uncover nearby neutron stars where the jet is not pointed towards the earth. In this work, we study the prospects of finding glitching neutron stars using a generic all-sky search for short-duration gravitational wave transients. We set upper limits for the third observing run of the LIGO--Virgo detectors and present the prospects for upcoming observing runs of LIGO, Virgo, KAGRA, and LIGO India. We find the detectable glitch size will be around $10^{-5}$\,Hz for the fifth observing run for pulsars with spin frequency and distance comparable to the Vela pulsar. We also present the prospects of localizing the direction in the sky of these sources with gravitational waves alone, which can facilitate electromagnetic follow-up. We find that for the five detector configuration, the localization capability for a glitch size of $10^{-5}$\,Hz is around 200 square degrees at $1\sigma$ confidence for $50\%$ of events with distance and spin frequency as that of Vela.

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is the most sensitive ground-based, single-dish radio telescope on Earth. However, the original HI spectra produced by FAST are affected by standing waves. To maximize the power of FAST for high-sensitivity observations, we proposed an algorithm that combines fast Fourier transforms and extreme envelope curves to automatically correct the baselines of FAST HI spectra and remove standing waves from the baselines. This algorithm can reduce the amplified noise level caused by standing waves to a near-ideal level without losing signals or introducing false signals. The root mean square of the average baseline reaches $\sim$ 8 mK, approaching the theoretical sensitivity of an HI spectrum produced by FAST for an integration time of 335 minutes, i.e., $\sim$ 6 mK.

Temperature asymmetry in the cosmic microwave background (CMB) data by the Planck satellite has been discovered and analyzed toward several nearby edge-on spiral galaxies. It provides a way to probe galactic halo rotation, and to constrain the baryon fraction in the galactic halos. The frequency independence of the observed data provides a strong indication of the Doppler shift nature of the effect, due to the galactic halo rotation. It was proposed that this effect may arise from the emission of cold gas clouds populating the galactic halos. However, in order to confirm this view, other effects that might give rise to a temperature asymmetry in the CMB data, have to be considered and studied in detail. The main aim of the present paper is to estimate the contribution in the CMB temperature asymmetry data due to the free-free emission by hot gas (particularly electrons) through the rotational kinetic Sunyaev-Zeldovich (rkSZ) effect. We concentrate, in particular, on the M31 galactic halo and compare the estimated values of the rkSZ induced temperature asymmetry with those obtained by using the SMICA pipeline of the Planck data release, already employed to project out the SZ sources and for lensing studies. As an additional consistency check, we also verified that the hot gas diffuse emission in the X-ray band does not exceed that detected in the soft X-ray band by ROSAT observations. We note that our results clearly show that the rkSZ effect gives only a minor contribution to the observed M31 halo temperature asymmetry by Planck data.

We present an analytical study of light curves of slowly rotating pulsars with emphasis on the chromatic effects derived from the presence of a plasma environment; analyzing the effects of the compactness and charge of the star, the metric model, and the electronic plasma density profile. After doing a numerical integration of the trajectories and luminosity curves of pulsars for different spherically symmetric metrics representing the exterior region of the pulsar, we generalize the approximate Beloborodov formula in order to include plasma corrections, obtaining simple analytical expressions for the trajectories and the observed flux and significantly simplifying the calculation of the pulse profiles by a drastic reduction of their computational cost. We study the errors committed by our approximation, comparing the numerical and analytical procedures. We also show how to use the new formalism to model the flux coming from different emission caps, not necessarily circular or antipodal and including the case of ring-shaped hot spots. Finally, we extend the classification introduced by Beloborodov to the case of two distinguishable, non-antipodal, finite size emission caps, showing the respective classification maps and some of the characteristic pulse profiles.

Close-by planets may excite various kinds of oscillations in their host stars through their time-varying tidal potential. Magnetostrophic oscillations with a frequency much smaller than the stellar rotation frequency have recently been proposed to account for the spin-orbit commensurability observed in several planet-hosting stars. In principle, they can be resonantly excited in an isolated slender magnetic flux tube by a Fourier component of the time-varying tidal potential with a very low frequency in the reference frame rotating with the host. However, due to the weakness of such high-order tidal components, a mechanism is required to lock the oscillations in phase with the forcing for long time intervals ($10^{3}-10^{7}$ years) in order to allow the oscillation amplitude to grow. We propose that the locking mechanism is an autoresonance produced by the non-linear dependence of the oscillation frequency on its amplitude. We suggest that the angular momentum loss rate is remarkably reduced in hosts entering autoresonance that contributes to maintain those systems in that regime for a long time. We apply our model to a sample of ten systems showing spin-orbit commensurability and estimate the maximum drifts of the relevant tidal potential frequencies that allow them to enter the autoresonant regime. Such drifts are compared with the expected drifts owing to the tidal evolution of the planetary orbits and the stellar angular momentum loss in the magnetized winds finding that autoresonance is a viable mechanism in eight systems, at least in our idealized model. The duration of the autoresonant regime and the associated spin-orbit commensurability may be comparable with the main-sequence lifetimes of the host stars, indicating that gyrochronology may not be applicable to those hosts.

We report the discovery of a new short period pulsating variable in the field of exoplanet host star XO-2. Variable has been identified while it was being used as a comparison star. In order to verify the variability of the candidate, a follow-up program was carried out. Period analysis of multi-band light curves revealed a very prominent and consistent pulsation periodicity of $P\sim0.95$ hours. Given the variability period, amplitude and the color index, the object is most likely a \emph{Delta Scuti} type variable. Absolute magnitude ($M_{v}$) and the color index $(B-V)_{0}$ of the star determined as $2.76$ and $0.22$, respectively. This $(B-V)_{0}$ of the star corresponds to A7 spectral type with an approximate effective temperature of 7725 K. Machine-learning analysis of the time-series data also revealed that the object is of variable type DSCT with a probability of 78\%.

This is an exciting era for exo-planetary exploration. In the past two decades, astronomers have harvested data from all the observatories at their disposal. Those collective efforts allowed us to have a glimpse at the convoluted process of planetary formation and evolution and its connections to atmospheric compositions, but nevertheless remained limited by the low quality and scarcity of exo-atmospheric data. Now, the recently launched JWST, and other upcoming space missions such as Ariel, Twinkle and ELTs are set to anew the landscape, bringing fresh insights to these remote worlds. However, with new opportunities come new challenges. The field of exoplanet atmospheres is already struggling with the incoming volume and quality of data, and machine learning (ML) techniques lands itself as a promising alternative. Developing techniques of this kind is an inter-disciplinary task, one that requires domain knowledge of the field, access to relevant tools and expert insights on the capability and limitations of current ML models. These stringent requirements have so far limited the developments of ML in the field to a few isolated initiatives. As part of the data product of the NeurIPS 2022 Data challenge, we would like to present the Ariel Big Challenge Database (ABC Database), a carefully designed, organised and publicly available database. With 105,887 forward models, 26,109 complementary posterior distributions and an easy-to-understand documentation, this represents an unprecedented effort to invite cross-disciplinary experts to the study of the inverse problem in the context of exoplanetary studies.

The study of extra-solar planets, or simply, exoplanets, planets outside our own Solar System, is fundamentally a grand quest to understand our place in the Universe. Discoveries in the last two decades have re-defined our understanding of planets, and helped us comprehend the uniqueness of our very own Earth. In recent years the focus has shifted from planet detection to planet characterisation, where key planetary properties are inferred from telescope observations using Monte Carlo-based methods. However, the efficiency of sampling-based methodologies is put under strain by the high-resolution observational data from next generation telescopes, such as the James Webb Space Telescope and the Ariel Space Mission. We are delighted to announce the acceptance of the Ariel ML Data Challenge 2022 as part of the NeurIPS competition track. The goal of this challenge is to identify a reliable and scalable method to perform planetary characterisation. Depending on the chosen track, participants are tasked to provide either quartile estimates or the approximate distribution of key planetary properties. To this end, a synthetic spectroscopic dataset has been generated from the official simulators for the ESA Ariel Space Mission. The aims of the competition are three-fold. 1) To offer a challenging application for comparing and advancing conditional density estimation methods. 2) To provide a valuable contribution towards reliable and efficient analysis of spectroscopic data, enabling astronomers to build a better picture of planetary demographics, and 3) To promote the interaction between ML and exoplanetary science. The competition is open from 15th June and will run until early October, participants of all skill levels are more than welcomed!

The 511 keV gamma-ray emission from the galactic center region may fully or partially originate from the annihilation of positrons from dark matter particles with electrons from the interstellar medium. Alternatively, the positrons could be created by astrophysical sources, involving exclusively standard model physics. We describe here a new concept for a 511 keV mission called 511-CAM (511 keV gamma-ray CAmera using Micro-calorimeters) that combines focusing gamma-ray optics with a stack of Transition Edge Sensor (TES) microcalorimeter arrays in the focal plane. The 511-CAM detector assembly has a projected 511 keV energy resolution of 390 eV Full Width Half Maximum (FWHM) or better, and improves by a factor of at least 11 on the performance of state-of-the-art Ge-based Compton telescopes. Combining this unprecedented energy resolution with sub-arcmin angular resolutions afforded by Laue lens or channeling optics could make substantial contributions to identifying the origin of the 511 keV emission by discovering and characterizing point sources and measuring line-of-sight velocities of the emitting plasmas.

We trace the overall connectivity of the cosmic web as defined by haloes in the Planck-Millennium simulation using the persistence and Betti curve analysis developed in our previous papers. We consider the presence of clustering in excess of the second-order correlation function, and investigate the extent to which the dark matter haloes reflect the intricate web-like pattern of the underlying dark matter distribution. With our systematic topological analysis we correlate local information and halo properties with the multi-scale geometrical environment of the cosmic web, delineated by elongated filamentary bridges and sheetlike walls that connect compact clusters at the nodes and define the boundaries of near-empty voids. We capture the multi-scale topology traced by the discrete spatial halo distribution through filtering the distance field of the corresponding Delaunay tessellation. The tessellation is naturally adaptive to the local density, perfectly outlining the local geometry. The resulting nested alpha shapes contain the complete information on the multi-scale topology. Normalising second-order clustering, we find a remarkable linear relationship between halo masses and topology: haloes of different mass trace environments with different topological signature. This is topological bias, a bias independent of the halo clustering bias associated with the two-point correlation function. Topological bias can be viewed as an environmental structure bias. We quantify it through a linear relation accounting for selection effects in the analysis and interpretation of the spatial distribution of galaxies. This mass-dependent scaling relation allows us to take clustering into account and determine the overall connectivity based on a limited sample of galaxies. This is of particular relevance with large upcoming galaxy surveys such as DESI, Euclid, and the Vera Rubin telescope surveys.

Many exoplanets were detected thanks to the radial velocity method, according to which the motion of a binary system around its center of mass can produce a periodical variation of the Doppler effect of the light emitted by the host star. These variations are influenced by both Newtonian and non-Newtonian perturbations to the dominant inverse-square acceleration; accordingly, exoplanetary systems lend themselves to test theories of gravity alternative to General Relativity. In this paper, we consider the impact of Standard Model Extension (a model that can be used to test all possible Lorentz violations) on the perturbation of radial velocity, and suggest that suitable exoplanets configurations and improvements in detection techniques may contribute to obtain new constraints on the model parameters.

The Evolutionary Map of the Universe (EMU) large-area radio continuum survey will detect tens of millions of radio galaxies, giving an opportunity for the detection of previously unknown classes of objects. To maximise the scientific value and make new discoveries, the analysis of this data will need to go beyond simple visual inspection. We propose the coarse-grained complexity, a simple scalar quantity relating to the minimum description length of an image, that can be used to identify images that contain complex and unusual structures. The complexity can be computed without reference to the ensemble or existing catalogue data, making the computation efficient on surveys at very large scales (such as the full EMU survey). We apply our coarse-grained complexity measure to data from the EMU Pilot Survey to detect and confirm anomalous objects in this data set and produce an anomaly catalogue. Rather than work with existing catalogue data using a specific source detection algorithm, we perform a blind scan of the area, computing the complexity using a sliding square aperture. The effectiveness of the complexity measure for identifying anomalous objects is evaluated using crowd-sourced labels generated via the Zooniverse.org platform. We find that the complexity scan captures unusual sources, such as odd radio circles, in the high-value tail of the complexity distribution. We use this distribution to produce catalogues of the 5%, 1% and 0.5% most complex frames with the largest catalogue estimated to be 86% complete and the smallest catalogue 94% pure.

Giant planets can interact with multiple and chemically diverse environments in protoplanetary discs while they form and migrate to their final orbits. The way this interaction affects the accretion of gas and solids shapes the chemical composition of the planets and of their atmospheres. Here we investigate the effects of different chemical structures of the host protoplanetary disc on the planetary composition. We consider both scenarios of molecular (inheritance from the pre-stellar cloud) and atomic (complete chemical reset) initial abundances in the disc. We focus on four elemental tracers of different volatility: C, O, N, and S. We explore the entire extension of possible formation regions suggested by observations by coupling the disc chemical scenarios with N-body simulations of forming and migrating giant planets. The planet formation process produces giant planets with chemical compositions significantly deviating from that of the host disc. We find that the C/N, N/O, and S/N ratios follow monotonic trends with the extent of migration. The C/O ratio shows a more complex behaviour, dependent on the planet accretion history and on the chemical structure of the formation environment. The comparison between S/N* and C/N* (where * indicates normalisation to the stellar value), constrains the relative contribution of gas and solids to the total metallicity. Giant planets whose metallicity is dominated by the contribution of the gas are characterised by N/O* > C/O* > C/N* and allow to constrain the disc chemical scenario. When the planetary metallicity is instead dominated by the contribution of the solids we find that C/N* > C/O* > N/O*.

We present the first public release of ShapePipe, an open-source and modular weak-lensing measurement, analysis, and validation pipeline written in Python. We describe the design of the software and justify the choices made. We provide a brief description of all the modules currently available and summarise how the pipeline has been applied to real Ultraviolet Near-Infrared Optical Northern Survey data. Finally, we mention plans for future applications and development. The code and accompanying documentation are publicly available on GitHub.

The growing population of compact binary mergers detected with gravitational waves contains multiple events that are challenging to explain through isolated binary evolution. Such events have higher masses than are expected in isolated binaries, component spin-tilt angles that are misaligned, and/or non-negligible orbital eccentricities. We investigate the close-to-merger orbital eccentricities of 62 binary black hole candidates from the third gravitational-wave transient catalogue of the LIGO-Virgo-KAGRA Collaboration, finding that at least four of these events show significant support for eccentricity $e_{10} \geq 0.1$ at a gravitational-wave frequency of $10$~Hz. Two of these events are new additions to the population: GW191109 and GW200208\_22. If the four eccentric candidates are truly eccentric, our results suggest that densely-populated star clusters may produce 100\% of the observed mergers. However, it remains likely that other formation environments with higher yields of eccentric mergers -- for example, active galactic nuclei -- also contribute. We estimate that we will be able to confidently distinguish which formation channel dominates the eccentric merger rate after $\gtrsim 80$ detections of events with $e_{10} \geq 0.05$ at LIGO--Virgo sensitivity, with only $\sim 5$ detectably-eccentric events required to distinguish formation channels with third-generation gravitational-wave detectors.

Kpc-scale triple active galactic nuclei (AGNs), potential precursors of gravitationally-bound triple massive black holes (MBHs), are rarely seen objects and believed to play an important role in the evolution of MBHs and their host galaxies. In this work we present a multi-band (3.0, 6.0 10.0, and 15.0 GHz), high-resolution radio imaging of the triple AGN candidate, SDSS J0849+1114, using the Very Large Array. Two of the three nuclei (A and C) are detected at 3.0, 6.0, and 15 GHz for the first time, both exhibiting a steep spectrum over 3--15 GHz (with a spectral index $-0.90 \pm 0.05$ and $-1.03 \pm 0.04$) consistent with a synchrotron origin. Nucleus A, the strongest nucleus among the three, shows a double-sided jet, with the jet orientation changing by $\sim20^{\circ}$ between its inner 1" and the outer 5.5" (8.1 kpc) components, which may be explained as the MBH's angular momentum having been altered by merger-enhanced accretion. Nucleus C also shows a two-sided jet, with the western jet inflating into a radio lobe with an extent of 1.5" (2.2 kpc). The internal energy of the radio lobe is estimated to be $\rm 5.0 \times 10^{55}$ erg, for an equipartition magnetic field strength of $\rm \sim 160\ \mu G$. No significant radio emission is detected at all four frequencies for nucleus B, yielding an upper limit of 15, 15, 15, and 18 $\rm \mu Jy\ beam^{-1}$ at 3.0, 6.0, 10.0, and 15.0 GHz, based on which we constrain the star formation rate in nucleus B to be $\lesssim 0.4~\rm M_{\odot}~yr^{-1}$.

We investigate the production of gravitational waves (GWs) during preheating with monomial/polynomial inflationary potentials, considering a trilinear coupling $\phi\chi^2$ between a daughter field $\chi$ and the inflaton $\phi$. For sufficiently large couplings, the trilinear interaction leads to an exponential production of $\chi$ particles, and as a result, a large stochastic GW background (SGWB) is generated throughout the process. We study the linear and non-linear dynamics of preheating with lattice simulations, following the production of GWs through all relevant stages. We find that large couplings lead to SGWBs with a large amplitude today, of the order of $h^2\Omega_{\rm GW}^{(0)} \simeq 5\cdot10^{-9}$. These backgrounds are however peaked at high frequencies $f_{\rm p} \sim 10^6-10^8$ Hz, which makes them undetectable by current/planned GW observatories. As the amount of GWs produced is in any case remarkable, we discuss the prospects for probing the SGWB indirectly by using constraints on the effective number of relativistic species in the universe $\Delta N_{\rm eff}$.

We provide perturbation theory predictions for the HI intensity mapping power spectrum multipoles using the Effective Field Theory of Large Scale Structure (EFTofLSS), which should allow us to constrain cosmological parameters exploiting mildly nonlinear scales. Assuming survey specifications typical of proposed interferometric HI intensity mapping experiments like CHORD and PUMA, and realistic ranges of validity for the perturbation theory modelling, we run mock full shape MCMC analyses at a redshift bin centred at $z=0.5$, and compare with Stage-IV optical galaxy surveys. We include the impact of 21cm foreground removal using simulations-based prescriptions, and quantify the effects on the precision and accuracy of the parameter estimation. We vary 10 parameters in total: 3 cosmological and 7 bias and counterterms parameters. Amongst them, the 4 parameters of interest are: the cold dark matter density, $\omega_{c}$, the Hubble parameter, $h$, the primordial amplitude of the power spectrum, $A_{s}$, and the linear HI bias, $b_1$. For the best case scenario, we obtain unbiased constraints on all parameters with $<3\%$ errors at $68\%$ confidence level. When we include the foreground removal effects, the parameter estimation becomes strongly biased, with all parameters being $>5\sigma$ away from the true values. We find that scale cuts $k_{min} \sim 0.03 \, h/Mpc$ are required to return accurate estimates for $\omega_{c}$ and $h$, at the price of a decrease in the precision, while $A_{s}$ and $b_1$ remain biased. We comment on the implications of these results for current and forthcoming real data analyses.

The discovery of faint FR~I radio jets in the nearby elliptical galaxy NGC 5322 is reported here using 144 MHz LOFAR image. The jets have an angular extent of $\sim40$ arcmin or a projected physical extent of $\sim350$ kpc. The faint jets remain well collimated and disappear in the intergalactic medium, without any visible hotspot or radio lobes. The jets detected up to $\sim20$ kpc extent at higher frequencies are relatively bright within the optical extent of the galaxy but become faint abruptly outside, where detection is made only in the LOFAR image. The total radio luminosity of the galaxy at 144 MHz is estimated to be $3.7(\pm0.4)\times10^{22}$ W Hz$^{-1}$. The 144 MHz radio luminosity of the faint jets outside the optical extent is estimated to be $7.1(\pm2.0)\times10^{21}$ W Hz$^{-1}$. The extent of the jets for its radio luminosity is abnormally large when compared to the general population of radio galaxies. It makes NGC 5322 a member of a rare population of radio galaxies, previously not detected in other radio surveys. A combined effect of stellar core depletion and low-density environment around the jets, inferred from previous studies in other wave-bands, resulting into weak entrainment of surrounding material to the jets could be responsible for its large size despite a low radio luminosity.

We analyze a 7.4 hr XMM-Newton light curve of the cataclysmic variable Swift J0503.7-2819, previously classified using optical periods as an intermediate polar (IP) with an orbital period of 0.0567 days. A photometric signal at 975 s, previously suggested to be the spin period, is not present in X-rays and is readily understood as a quasi-periodic oscillation. The X-ray light curve instead shows clear behavior of a highly asynchronous polar (AP) or stream-fed IP. It can be described by either of two scenarios: one which switches between one-pole and two-pole accretion, and another in which accretion alternates fully between two poles. The spin periods in these two models are 0.0455 days and 0.0505 days, respectively. The spin frequency $\omega$ is thus either 24% faster or 12% faster than the orbital frequency $\Omega$, and the corresponding beat period between spin and orbit is 0.231 days or 0.462 days. Brief absorption events seen in light curve are spaced in a way that may favor the longer spin and beat periods. These periods are confirmed and refined using data from the Transiting Exoplanet Survey Satellite (TESS) and the Asteroid Terrestrial-impact Last Alert System (ATLAS). The short beat cycle of Swift J0503.7-2819 makes it well-suited to resolving this common dilemma, which amounts to deciding whether the main signal in the power spectrum is $\omega$ or $2\omega-\Omega$.

Studies on the circumstellar structures around evolved stars provide vital information on the evolution of the parent star and the properties of the local interstellar medium. In this work, we present the discovery and characterization of an optical cocoon tail behind the star HD 185806. The cocoon apex emission is puzzling, as it is detected in the infrared but shows no signal in the optical wavelength. The H-alpha and [OIII] fluxes of the nebular structure vary from 2.7 to 8.5x10^{-12} erg s^{-1} cm^ {-2} and from 0.9 to 7.0x10^{-13} erg s^{-1} cm^{-2}, respectively. Through high-resolution spectroscopy, we derive the spectral type of the star, construct the position-velocity diagrams of the cocoon tail for the H-alpha, [OIII] and [NII] emission lines, and determine its velocity in the range of -100 to 40 km s ^{-1} . Furthermore, we use SED fitting and MESA evolutionary models adopting a distance of 900 pc, and classify HD 185806 as a 1.3 M star, in the transition phase between the RGB and early AGB stages. Finally, we study the morpho-kinematic structure of the cocoon tail using the astronomical software SHAPE. An ellipsoidal structure, with an inclination of 19 degrees with respect to the plane of sky is found to better reproduce the observed cocoon tail of HD 185806.

Neutrinos remain mysterious. As an example, enhanced self-interactions ($\nu$SI), which would have broad implications, are allowed. For the high neutrino densities within core-collapse supernovae, $\nu$SI could be important, but robust observables have been lacking. We show that $\nu$SI make neutrinos form a tightly coupled fluid that expands under relativistic hydrodynamics. The outflow becomes either a burst or a steady-state wind; which occurs here is uncertain. Though the diffusive environment where neutrinos are produced may make a wind more likely, further work is needed to determine when each case is realized. In the burst-outflow case, $\nu$SI increase the duration of the neutrino signal, and even a simple analysis of SN 1987A data has powerful sensitivity. For the wind-outflow case, we outline several promising ideas that may lead to new observables. Combined, these results are important steps towards solving the 35-year-old puzzle of how $\nu$SI impact supernovae.

We update dark radiation constraints on millicharged particle (MCP) and gauged baryon-number-minus-lepton-number ($B-L$) extensions of the Standard Model (SM). In these models, a massive SM gauge singlet mediator couples the SM plasma to additional SM-singlet light degrees of freedom. In the early Universe, these new light particles are populated via the interaction of the SM with the MCP, or the new $B-L$ gauge boson, and act as dark radiation. The presence of dark radiation in the early Universe is tightly constrained by current and upcoming cosmic microwave background (CMB) measurements. We update bounds on MCPs from current measurements of $N_{\rm eff}$ and show that future CMB experiments will be able to rule out or discover the extended MCP model invoked to explain the EDGES anomaly. Our analysis of the gauged $B-L$ model goes beyond previous studies by including quantum-statistical and out-of-equilibrium effects. Further, we account for the finite lifetime of the $B-L$ gauge boson, which boosts the subsequent right-handed neutrino energy density. We also develop a number of approximations and techniques for simplifying and solving the relevant Boltzmann equations. We use our approximations to develop a lower bound on the radiation density in a generic hidden sector with a light relic that is insensitive to the details of the hidden sector, provided the mediator interacts more strongly with the hidden sector than with the SM.

The phenomenon of gravitational particle production can take place for quantum fields in curved spacetime. The abundance and energy spectrum of gravitationally produced particles is typically calculated by solving the field's mode equations on a time-dependent background metric. For purposes of studying dark matter production in an inflationary cosmology, these mode equations are often solved numerically, which is computationally intensive, especially for the rapidly-oscillating high-momentum modes. However, these same modes are amenable to analytic evaluation via the Exact Wentzel-Kramers-Brillouin (EWKB) method, where gravitational particle production is a manifestation of the Stokes phenomenon. These analytic techniques have been used in the past to study gravitational particle production for spin-0 bosons. We extend the earlier work to study gravitational production of spin-1/2 and spin-3/2 fermions. We derive an analytic expression for the connection matrix (valid to all orders in perturbations) that relates Bogoliubov coefficients across a Stokes line connecting a merged pair of simple turning points. By comparing the analytic approximation with a direct numerical integration of the mode equations, we demonstrate an excellent agreement and highlight the utility of the Stokes phenomenon formalism applied to fermions. We discuss the implications for an analytic understanding of catastrophic particle production due to vanishing sound speed, which can occur for a spin-3/2 Rarita-Schwinger field.

We report a laboratory study of the transport of angular momentum by a turbulent flow of an electrically conducting fluid confined in a thin disk. When the electromagnetic force applied to the liquid metal is large enough, the corresponding volume injection of angular momentum produces a turbulent flow characterized by a time-averaged Keplerian rotation rate $\bar{\Omega}\sim r^{-3/2}$. Two contributions to the local angular momentum transport are identified: one from the poloidal recirculation induced by the presence of boundaries, and the other from turbulent fluctuations in the bulk. The latter produces efficient angular momentum transport independent of the molecular viscosity of the fluid, and leads to Kraichnan's prediction $\text{Nu}_\Omega\propto\sqrt{\text{Ta}}$. In this so-called ultimate regime, the experiment, therefore, provides a configuration analogous to accretion disks, allowing the prediction of accretion rates induced by Keplerian turbulence.

Motivated by quantum corrections to gravity which introduce higher order terms like $R^{2}$ or terms in which the Riemann tensor is not symmetric, we study the latter case in the form of a general Brans-Dicke type model containing the Ricci scalar, the Holst term and the Nieh-Yan invariant. We focus on the comparison between both the Einstein and the Jordan frames showing how, by considering a non minimal coupling, the torsion terms can be rewritten completely in terms of the scalar field. Furthermore, we discuss the role of the transformation of the torsion under conformal transformations and show that the transformation proposed in this paper (extended conformal transformation) contains a special case of the projective transformation of the connection which arises in a natural way. Moreover, we study the stability of the system via a dynamical analysis in the Jordan frame, this in order to analyze whether or not we have the fixed points that can be later identified as the inflationary attactor and the unstable fix point where inflation could take place. Finally we study the scale invariant case of our general model, we carry out the calculations in the Jordan frame and find out that both the scalar spectral index and the tensor to scalar ratio are in agreement with the latest Planck results.

The main mechanism responsible for Axion-Like-Particle (ALP) production in the early universe is the so-called misalignment mechanism. Three regimes have been investigated in this context: standard misalignment, large misalignment and kinetic misalignment. The latter applies if the axion inherits a large initial velocity in the early universe, such that the field rolls through many wiggles during its evolution, before it gets trapped in one minimum. This largely opens the region of parameter space for ALP dark matter towards higher values for the axion-photon coupling, which can be probed by the whole set of next decade's upcoming experiments. In fact, almost the entire parameter space in the [mass, decay constant] plane can now accommodate dark matter. In this paper, we show that in kinetic misalignment, the axion field is almost always entirely fragmented, meaning that the energy density of the homogeneous field is redistributed over higher-mode axions. We present a general model-independent analytical description of kinetic fragmentation, including discussion of the modified initial conditions for the mode functions due to the axion's initial velocity, and how they impact the growth of the adiabatic fluctuations. We calculate precisely the parameter regions corresponding respectively to standard misalignment, kinetic misalignment with weak fragmentation, fragmentation after trapping and fragmentation before trapping. While axion fragmentation can impact the precise determination of the relic abundance, another main observational implication is the formation of much denser compact axion halos, that is described in a companion paper. We also point out a new gravitational-wave signature that arises in the large misalignment regime with complete fragmentation and could be seen in measurements of $\mu$ distortions in the Cosmic Microwave Background.

We study an asymmetric dark matter model with self-interacting dark matter consisting of a Dirac fermion $\chi$ coupled to a scalar or vector mediator, such that the reaction $\chi + \chi \to \chi + \chi$ is well described by perturbation theory. We compute the scattering cross section $\sigma$, the transfer cross section $\sigma_T$, and the viscosity cross section $\sigma_V$ for this reaction. As one part of our study, we give analytic and numerical comparisons of results obtained with the inclusion of both $t$-channel and $u$-channel exchanges and results obtained in an approximation that has often been used in the literature that includes only the $t$-channel contribution. The velocity dependences of these cross sections are studied in detail and shown to be in accord with observational data.

The intrinsic background count rate of tungsten superconducting transition-edge sensors (TES) is low, and the calorimeters using these sensors can resolve the energy of single photons. These facts make the sensors particularly interesting for the background-limited searches of new processes and particles. In this contribution, the intrinsic background of a tungsten TES has been investigated. After excluding other sources (e.g., cosmic muons, thermal background) relevant for the observed background rate of $10^{-4}$~s$^{-1}$ for the detection of photons with a wave length of 1064 nm, we investigate the impact of natural radioactivity. Dedicated measurements using gamma-emitters mounted outside the cryostat have been used to estimate the sensitivity of the TES setup for ionizing radiation. We have found that indeed an increased background can be observed in the presence of the radioactive sources. After selecting events which populate our signal region tuned for single photon detection at near-infrared, roughly 0.5% of the events produced by gamma-rays appear indistinguishable from those due to single photons with 1064~nm wave length. This ratio is consistent with that observed for the residual background detected with the TES at a rate of $10^{-4}$~s$^{-1}$. From this, we conclude that the bulk of the observed background count-rate in the signal region can be explained by natural radioactivity.

The asymptotically safe gravity is based on the idea that the main contribution to the Schwarzschild-like black hole spacetime is due to the value of the gravitational coupling which depends on the distance from the origin and approaches its classical value in the far zone. However, at some stage this approach has an arbitrariness of choice of some identification parameter. The two cases of identification are considered here: first, by the modified proper length (the Bonanno-Reuter metric), and second, by the Kretschmann scalar (the Held-Gold-Eichhorn metric, which coincides, up to the redefinition of constants, with the Hayward metric). Even though the quasinormal modes of these metrics have been extensively studied, a number of interesting points were missed. We have found that quasinormal modes are qualitatively similar for both types of identification. The deviation of the fundamental mode from its Schwarzschild limit may be a few times larger than it was claimed in the previous studies. The striking deviation from the Schwarzschild limit occurs for overtones, being as large as hundreds of percent even when the fundamental mode is almost coinciding with the Schwarzschild one. This happens because the above metrics are very close to the Schwarzschild one everywhere, except a small region near the event horizon, which is crucial for overtones. The spectrum of both metrics contains purely imaginary (non-oscillatory) modes, which, for some values of parameters, can appear already at the second overtone.

Motivated by the growing evidence for a large neutrino asymmetry in the early universe from the recent $^4{\rm He}$ measurements, we point out the class of leptogenesis scenarios with decay or scattering being the source of lepton asymmetry, simultaneously consistent with such a large neutrino asymmetry as well as the observed baryon asymmetry of the universe. Considering $1 \rightarrow 2, 1 \rightarrow 3$ as well as $2 \rightarrow 2$ processes to be responsible for generating the asymmetries, we show that only TeV scale leptogenesis preferably of $1 \rightarrow N \, (N \geq 3)$ type can generate the required lepton asymmetry around sphaleron temperature while also generating a large neutrino asymmetry $\sim \mathcal{O}(10^{-2})$ by the epoch of the big bang nucleosynthesis. This also offers the possibility of cogenesis if dark matter is in the form of a sterile neutrino resonantly produced in the early universe due to the presence of a large neutrino asymmetry. While such low scale leptogenesis has tantalising detection prospects at laboratory experiments, the indication of a large neutrino asymmetry provides a complementary indirect signature.