Papers for Monday, Dec 11 2023

We report that HD 110067, the recently announced host star of a resonant sextuplet of transiting sub-Neptunes, is not a single star as claimed in the discovery paper, but a wide hierarchical triple. The K0 V planet hosting star (V = 8.4 mag, d = 32 pc) has a companion at a wide projected separation of 13400 au. This companion, namely HD 110106, is a slightly fainter (V = 8.8 mag) K3 V type 8-year period double-lined spectroscopic binary. The secondary in this spectroscopic binary is contributing a significant amount of flux and has a measured high mass ratio.

Constraining turbulence in disks is key towards understanding their evolution through the transport of angular momentum. Until now measurements of high turbulence have remained elusive and methods for estimating turbulence relay mostly on complex radiative transfer models of the data. Using the disk emission from IM Lup, a source proposed to be undergoing Magneto-Rotational Instabilities (MRI) and possibly have high turbulence values in the upper disk layers, we present a new way of directly measuring turbulence without need of radiative transfer or thermochemical models. Through the characterization of the CN and C$_2$H emission in IM Lup, we aim to connect the information on the vertical and thermal structure of a particular disk region to derive turbulence at that location. By using an optically thin tracer it is possible to directly measure turbulence from the non-thermal broadening of the line. The vertical layers of the CN and C$_2$H emission are traced directly from the channel maps using ALFAHOR. By comparing their position to that of optically thick CO observations we are able to characterize the kinetic temperature of the emitting region. Using a simple parametric model of the line intensity with DISCMINER we accurately measure the emission linewidth and separate the thermal and non-thermal components. Assuming that the non-thermal component is fully turbulent, we are able to directly estimate the turbulent motions at the studied radial and vertical location of CN emission. IM Lup shows high turbulence of Mach 0.4-0.6 at $z/r \sim$ 0.25. Considering previous estimates of low turbulence near the midplane, this may indicate a vertical gradient in the disk turbulence, which is a key prediction of MRI studies. CN and C$_2$H are both emitting from a localized upper disk region at $z/r =$0.2-0.3, in agreement with thermochemical models.

Strongly-lensed supernovae are rare and valuable probes of cosmology and astrophysics. Upcoming wide-field time-domain surveys, such as the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST), are expected to discover an order-of-magnitude more lensed supernovae than have previously been observed. In this work, we investigate the cosmological prospects of lensed type Ia supernovae (SNIa) in LSST by quantifying the expected annual number of detections, the impact of stellar microlensing, follow-up feasibility, and how to best separate lensed and unlensed SNIa. We simulate SNIa lensed by galaxies, using the current LSST baseline v3.0 cadence, and find an expected number of 44 lensed SNIa detections per year. Microlensing effects by stars in the lens galaxy are predicted to lower the lensed SNIa detections by $\sim 8 \%$. The lensed events can be separated from the unlensed ones by jointly considering their colours and peak magnitudes. We define a `gold sample' of $\sim 10$ lensed SNIa per year with time delay $> 10$ days, $> 5$ detections before light-curve peak, and sufficiently bright ($m_i < 22.5$ mag) for follow-up observations. In three years of LSST operations, such a sample is expected to yield a $1.5\%$ measurement of the Hubble constant.

The ASSESS project aims to determine the role of episodic mass-loss in the evolution of massive stars. As a first step, we construct a catalog of spectroscopically identified dusty, evolved massive stars in ten southern galaxies for which Spitzer point-source catalogs are available. We conducted multi-object spectroscopy of dusty massive star candidates in these galaxies (spanning Z = 0.06-1.6 Zo) using the VLT. We obtained 763 spectra in WLM, NGC 55, NGC 247, NGC 253, NGC 300, NGC 1313, NGC 3109, Sextans A, M83 and NGC 7793. The targets were selected using their Spitzer photometry, by prioritizing targets with a strong infrared excess. We determined a spectral classification for each target. Additionally, we used archival images from the HST to provide a visual classification for 80 targets, as a star, cluster, or galaxy. We provide a catalog of 541 spectroscopically classified sources including 185 massive stars, of which 154 are newly classified massive stars. The catalog contains 129 red supergiants, 27 blue supergiants, 10 yellow supergiants, four luminous blue variable candidates, seven supergiant B[e] stars and eight emission line objects. Evidence for circumstellar dust is found in 24% of these massive stars, based on their infrared colors. We report a success rate of 28% for identifying massive stars among our observed spectra, while the average success rate of our priority system in selecting evolved massive stars was 36%. Additionally, the catalog contains 21 background galaxies (including AGN and quasars), 10 carbon stars and 99 HII regions. We measured the line ratios [NII]/Ha and [SII]/Ha for 76 HII regions and 36 other spectra with nebular emission-lines, thereby identifying eight sources with shocked emission. We present the largest catalog of evolved massive stars and in particular of red supergiants in nearby galaxies at low Z beyond the Local Group.

Simulations and indirect observational evidence have suggested that, in addition to the mergers of compact objects, there exists a secondary source of heavy element ($r$-process) nucleosynthesis with a short delay from star formation: the core-collapse of rapidly-rotating and/or highly-magnetized massive stars. Here, we probe a predicted signature of $r$-process enrichment, a late-time ($\gtrsim 40$~days post-burst) distinct red color, in observations of gamma-ray burst supernovae (GRB-SNe) which are linked to these massive star progenitors. We present optical to near-IR color measurements of four GRB-SNe at $z < 0.4$, extending out to $>$ 500 days post-burst, obtained with the Hubble Space Telescope and large-aperture ground-based telescopes. Comparison of our observations to models indicates that GRB 190829A favors little ($\leq 0.01 M_{\odot}$) $r$-process enrichment whereas GRB 100316D is consistent with producing $0.03 - 0.15 M_{\odot}$ of $r$-process material. Observations of GRBs 030329 and 130427A are not on sufficient timescales to robustly constrain enrichment, although taken together the sample of GRB-SNe indicates color diversity at late times. Our sample also disfavors large amounts of mixing between the inner $r$-process ejecta and outer SN layers. Our derived yields from GRB-SNe may be underestimated due to $r$-process material hidden in the SN ejecta (potentially due to low mixing fractions) or the limits of current models in measuring $r$-process mass. We conclude with recommendations for future search strategies to observe and probe the full distribution of $r$-process produced by GRB-SNe.

One of the primary scientific objectives of the Laser Interferometer Space Antenna (LISA) is to probe the expansion of the Universe using gravitational wave observations. Indeed, as gravitational waves from the coalescence of a massive black hole binary (MBHB) carry direct information of the luminosity distances, an accompanying electromagnetic (EM) counterpart can be used to determine the redshift. This method of $bright$ $sirens$ enables one to build a gravitational Hubble diagram to high redshift when applied to LISA. In this work, we forecast the ability of LISA-detected MBHB bright sirens to constrain cosmological models. As the expected EM emission from MBHBs can be detected up to redshift $z\sim 7$ with future astronomical facilities, we focus on the ability of LISA to constrain the expansion of the Universe at $z\sim 2-3$, a poorly charted epoch in cosmography. We find that a model-independent approach to cosmology based on a spline interpolation of the luminosity distance-redshift relation, can constrain the Hubble parameter at $z\sim2-3$ with a relative precision of at least $10\%$.

We present six spectroscopically confirmed massive protostructures, spanning a redshift range of $2.5<z<4.5$ in the Extended Chandra Deep Field South (ECDFS) field discovered as part of the Charting Cluster Construction in VUDS and ORELSE (C3VO) survey. We identify and characterize these remarkable systems by applying an overdensity measurement technique on an extensive data compilation of public and proprietary spectroscopic and photometric observations in this highly studied extragalactic field. Each of these six protostructures, i.e., a large scale overdensity (volume $>9000$\thinspace cMpc$^3$) of more than $2.5\sigma_{\delta}$ above the field density levels at these redshifts, have a total mass $M_{tot}\ge10^{14.8}M_\odot$ and one or more highly overdense (overdensity$\thinspace>5\sigma_{\delta}$) peaks. One of the most complex protostructures discovered is a massive ($M_{tot}=10^{15.1}M_\odot$) system at $z\sim3.47$ that contains six peaks and 55 spectroscopic members. We also discover protostructures at $z\sim3.30$ and $z\sim3.70$ that appear to at least partially overlap on sky with the protostructure at $z\sim3.47$, suggesting a possible connection. We additionally report on the discovery of three massive protostructures at $z=2.67$, 2.80, and 4.14 and discuss their properties. Finally, we discuss the relationship between star formation rate and environment in the richest of these protostructures, finding an enhancement of star formation activity in the densest regions. The diversity of the protostructures reported here provide an opportunity to study the complex effects of dense environments on galaxy evolution over a large redshift range in the early universe.

We simulate galaxy properties and redshift estimation for SPHEREx, the next NASA Medium Class Explorer. To make robust models of the galaxy population and test spectro-photometric redshift performance for SPHEREx, we develop a set of synthetic spectral energy distributions based on detailed fits to COSMOS2020 photometry spanning 0.1-8 micron. Given that SPHEREx obtains low-resolution spectra, emission lines will be important for some fraction of galaxies. Here we expand on previous work, using better photometry and photometric redshifts from COSMOS2020, and tight empirical relations to predict robust emission line strengths and ratios. A second galaxy catalog derived from the GAMA survey is generated to ensure the bright ($m_{AB}<18$ in the i-band) sample is representative over larger areas. Using template fitting to estimate photometric continuum redshifts, we forecast redshift recovery of 19 million galaxies over 30000 sq. deg. with $\sigma_z<0.003(1+z)$, 445 million with $\sigma_z<0.1(1+z)$ and 810 million with $\sigma_z<0.2(1+z)$. We also find through idealized tests that emission line information from spectrally dithered flux measurements can yield redshifts with accuracy beyond that implied by the naive SPHEREx channel resolution, motivating the development of a hybrid continuum-line redshift estimation approach.

The Event Horizon Telescope (EHT) provides an avenue to study black hole accretion flows on event-horizon scales. Fitting a semi-analytical model to EHT observations requires the construction of synthetic images, which is computationally expensive. This study presents an image generation tool in the form of a generative machine learning model, which extends the capabilities of a variational autoencoder. This tool can rapidly and continuously interpolate between a training set of images and can retrieve the defining parameters of those images. Trained on a set of synthetic black hole images, our tool showcases success in both interpolating black hole images and their associated physical parameters. By reducing the computational cost of generating an image, this tool facilitates parameter estimation and model validation for observations of black hole system.

Using a set of clusters in dark matter only cosmological simulations, we study the consequences of merging of clusters and groups of galaxies (with mass ratio larger than 5:1) to investigate the tidal impact of mergers on the satellite halos. We compare our results to a control sample of clusters that have had no major mergers over the same time period. Clusters that undergo major mergers are found to have a significant enhancement in destruction of their subhalos of ~10-30%, depending on how major the merger is. Those with mass ratios less than 7:1 showed no significant enhancement. The number of destroyed subhalos are measured for the cluster members that were inside the virial radius of clusters before the merger begins. This means preprocessed galaxies brought in by the merger are deliberately excluded, allowing us to clearly see the enhanced destruction purely as a result of the distorted and disturbed tidal field of the cluster during the merger. We also consider secondary parameters affecting the destruction of those satellites but find that the major mergers are the dominant factor. These results highlight how major mergers can significantly impact the cluster population, with likely consequences for the formation of intracluster light, and enhancement of tidal features in the remaining satellites.

The recently observed population of 540 free-floating Jupiter-mass objects, including 40 dynamically soft pairs in the Trapezium cluster have raised interesting questions on their formation and evolution. We test various scenarios for the origin and survivability of these free floating Jupiter-mass objects and Jupiter-mass Binary Objects (JuMBOs) in the Trapezium cluster. The numerical calculations are performed by direct N-body integration of the stars and planets in the Trapezium cluster starting with a wide variety of planets in various configurations. We discuss four models: SPP, in which selected stars have two outer orbiting Jupiter-mass planets; SPM, where selected stars are orbited by Jupiter-mass planet-moon pairs; ISF in which JuMBOs form in situ with the stars, and FFC, where we introduce a population of free-floating single Jupiter-mass objects, but no initialized binaries. Models FFC and SPP fail to produce enough JuMBOs. Models SPM can produce sufficient JuMBOs, but requires unusually wide orbits for the planet-moon system around the star. The observed JuMBOs and free-floating Jupiter-mass objects in the Trapezium cluster are best reproduced if they formed in pairs and as free-floaters together with the other stars in a smooth (Plummer) density profile with a virial radius of 0.5pc. A fractal stellar distribution also works, but requires relatively recent formations (>0.2Myr after the other stars formed) or a high (50%) initial binary fraction. This would make the primordial binary fraction of JuMBOs even higher than the already large observation fraction of 8%. The fraction of JuMBOs will continue to drop with time, and the lack of JuMBOs in Upper Scorpius could then result in its higher age, causing more JuMBOs to be ionized. We then also predict that the interstellar density of Jupiter-mass objects (mostly singles with 2% lucky surviving binaries) is 0.05/pc$^{3}$.

The High Energy X-ray Probe is a proposed NASA probe-class mission that combines the power of high angular resolution with a broad X-ray bandpass to provide the necessary leap in capabilities to address the important astrophysical questions of the next decade. HEX-P achieves breakthrough performance by combining technologies developed by experienced international partners. HEX-P will be launched into L1 to enable high observing efficiency. To meet the science goals, the payload consists of a suite of co-aligned X-ray telescopes designed to cover the 0.2 - 80 keV bandpass. The High Energy Telescope (HET) has an effective bandpass of 2 - 80 keV, and the Low Energy Telescope (LET) has an effective bandpass of 0.2 - 20 keV. The combination of bandpass and high observing efficiency delivers a powerful platform for broad science to serve a wide community. The baseline mission is five years, with 30% of the observing time dedicated to the PI-led program and 70% to a General Observer (GO) program. The GO program will be executed along with the PI-led program.

A notable fraction of helium observations at 1083~nm, probing evaporating atmospheres of short-period gas giants, exhibit a blueshift during transit, which might be indicative of a day-to-night side flow. In this study, we explore the gas dynamic effects of day-to-night temperature contrasts on the escaping atmosphere of a tidally locked planet. Using a combination of 3D hydrodynamic simulations and radiative transfer post-processing, we model transmission spectra of the metastable helium triplet. The key findings are: (1) Increasing day-night anisotropy leads to a narrowing of the helium line and an increase in the blueshift of the line centroid of a few km/s. (2) The velocity shift of the line depends on the line forming altitude, with higher planetary mass-loss rates causing the line to form at higher altitudes, resulting in a more pronounced velocity shift. (3) A critical point of day-night anisotropy exists at which the blueshift saturates due to turbulent flows generated by outflow material falling back onto the planet's night side. (4) A strong stellar wind and the presence of turbulent flows may induce time variations in the velocity shift. Assuming that the day-night temperature gradient is the main cause of the observed blueshifts in the He-1083 nm triplet, the correlation between the velocity shift and day-night anisotropy offers the opportunity to constrain the temperature gradient of the line forming region.

The Gaia-ESO Survey (GES) is a large public spectroscopic survey which acquired spectra for more than 100000 stars across all major components of the Milky Way. In addition to atmospheric parameters and stellar abundances that have been derived in previous papers of this series, the GES spectra allow us to detect spectroscopic binaries with one (SB1), two (SB2) or more (SBn $\ge$ 3) components. Cross-correlation functions (CCFs) have been re-computed thanks to a dozen spectral masks probing a range of effective temperatures, surface gravities and metallicities. By optimising the mask choice for a given spectrum, the new computed so-called Nacre (Narrow cross-correlation experiment) CCFs are narrower and allow to unblend more stellar components than standard masks. The Doe (Detection of Extrema) extremum-finding code then selects the individual components and provides their radial velocities. From the sample of HR10 and HR21 spectra corresponding to 37565 objects, the present study leads to the detection of 322 SB2, ten (three of them being tentative) SB3, and two tentative SB4. In particular, compared to our previous study, the Nacre CCFs allow us to multiply the number of SB2 candidates by $\approx$ 1.5. The colour-magnitude diagram reveals, as expected, the shifted location of the SB2 main sequence. A comparison between the SB identified in Gaia DR3 and the ones detected in the present work is performed and the complementarity of the two censuses is discussed. An application to mass-ratio determination is presented, and the mass-ratio distribution of the GES SB2 is discussed. When accounting for the SB2 detection rate, an SB2 frequency of $\approx$ 1.4% is derived within the present stellar sample of mainly FGK-type stars. As primary outliers identified within the GES data, SBn spectra produce a wealth of information and useful constraints for the binary population synthesis studies.

We present the kinematic anaylsis of $246$ stars within $4^\prime$ from the center of Orion Nebula Cluster (ONC), the closest massive star cluster with active star formation across the full mass range, which provides valuable insights in the the formation and evolution of star cluster on an individual-star basis. High-precision radial velocities and surface temperatures are retrieved from spectra acquired by the NIRSPEC instrument used with adaptive optics (NIRSPAO) on the Keck II 10-m telescope. A three-dimensional kinematic map is then constructed by combining with the proper motions previously measured by the Hubble Space Telescope (HST) ACS/WFPC2/WFC3IR and Keck II NIRC2. The measured root-mean-squared velocity dispersion is $2.26\pm0.08~\mathrm{km}\,\mathrm{s}^{-1}$, significantly higher than the virial equilibrium's requirement of $1.73~\mathrm{km}\,\mathrm{s}^{-1}$, suggesting that the ONC core is supervirial, consistent with previous findings. Energy equipartition is not detected in the cluster. Most notably, the velocity of each star relative to its neighbors is found to be negatively correlated with stellar mass. Low-mass stars moving faster than their surrounding stars in a supervirial cluster suggests that the initial masses of forming stars may be related to their initial kinematic states. Additionally, a clockwise rotation preference is detected. A weak sign of inverse mass segregation is also identified among stars excluding the Trapezium stars, though it could be a sample bias. Finally, this study reports the discovery of four new candidate spectroscopic binary systems.

Since its launch in 2013, the Gaia space telescope has provided precise measurements of the positions and magnitudes of over 1 billion stars. This has enabled extensive searches for stellar and sub-stellar companions through astrometric and radial velocity measurements. However, these surveys require a prior knowledge of any unresolved companion affecting the results which can be identified using photometry. In this work, Gaia's magnitude measurements are combined with near-infrared observations from 2MASS and WISE and simulation-based inference is applied to constrain astrophysical parameters and search for hidden companions. This method is first tested on simulated sets of binary stars before expanding to Gaia's non-single star catalogue. Using this test, a region is identified on the H-R diagram in which the method is the most accurate and all Gaia sources within that region are analysed. This analysis reproduces a known anti-correlation between metallicity and binary fraction. Finally, the method is applied to the nearby star cluster M67 and, using previous studies of the metallicity distribution, it is possible to improve constraints on binary fraction. From this the binary fraction in the cluster is calculated to vary from 30% in the outer cluster to 45% near the core. This is found to be significantly higher the 23% binary fraction calculated for the wider stellar neighbourhood.

Highly magnified stars residing in caustic crossing lensed galaxies at z ~ 0.7-1.5 in galaxy cluster lensing fields inevitably exhibit recurrent brightening events as they traverse a micro caustic network cast down by foreground intracluster stars. The detectable ones belong to Nature's most massive and luminous class of stars, with evolved blue supergiants being the brightest ones at optical wavelengths. Considering single stars in this work, we study to what extent intrinsic stellar parameters are measurable from multi-filter lightcurves, which can be obtained with optical/near-IR space telescopes during one or multiple caustic crossing events. We adopt a realistic model for the axisymmetric surface brightness profiles of rotating O/B stars and develop a numerical lensing code that treats finite-source-size effects. With a single micro caustic crossing, the ratio of the surface rotation velocity to the breakup value is measurable to an precision of ~ 0.1-0.2 for feasible observation parameters with current space telescopes, with all unknown intrinsic and extrinsic parameters marginalized over and without a degeneracy with inclination. Equatorial radius and bolometric luminosity can be measured to 1/3 and 2/3 of the fractional uncertainty in the micro caustic strength, for which the value is not known at each crossing but an informative prior can be obtained from theory. Parameter inference precision may be further improved if multiple caustic crossing events for the same lensed star are jointly analyzed. Our results imply new opportunities to survey individual massive stars in star-formation sites at z ~ 0.7-1.5 or beyond.

In this paper we detect double-lined spectroscopic binaries (SB2) in five open clusters: NGC 2243, NGC 2420, NGC 3532, NGC 6253 and NGC 6705 (M 11) using a method based on high values of the projected rotational velocity when they are fitted with single star spectral model. Observed spectra were obtained from ESO archive. The method was validated on sets of synthetic spectra for the single and binary stars. It is able to reliably select spectroscopic binaries without confusing them with single stars, if components in binary rotate slowly and radial velocity separation is sufficiently high. We found 60 SB2 candidates: two in NGC~2243, eight in NGC~2420 and NGC~3532, 17 in NGC 6253 and 25 in NGC~6705. Comparison with literature confirms 18 of them, thus we found 42 new SB2 candidates.

We study a sample of 14 spectroscopically confirmed Ly$\alpha$ Emitters (LAEs) in the late era of reionization (at redshift $z\approx6$) based on the JWST/NIRCam imaging dataset. These LAEs with high Ly$\alpha$ luminosity of $L$(Ly$\alpha$) $\sim10^{42.4-43.4}$ erg s$^{-1}$ have been covered by the (ongoing) COSMOS-Web survey (Kartaltepe et al. 2021; Casey et al. 2022) over $0.28$ deg$^2$ in four NIRCam bands (F115W, F150W, F277W, and F444W). With deep JWST imaging, we determine the UV continua with $M_{\rm UV}$ ranging from ${-}20.5$ to ${-}18.5$ mag. The UV slopes have a median value of $\beta \approx-2.1$, and the steepest slope may reach $\beta<-3$. Under an excellent spatial resolution of JWST, we identify three out of the sample as potential merging/interacting systems. The 14 LAEs (and their components) are compact in morphology residing substantially below the mass-size relation of high-$z$ galaxies. We further investigate the stellar mass ($M_*$) and star-formation rates (SFRs). About half of the LAEs lie on the SFR-$M_*$ main-sequence relation while two are either star-burst galaxies or likely to host active galactic nuclei (AGN), recently referred as "little red dots", implying a ${\sim}10\%$ AGN fraction. Moreover, we reveal that a new correlation may exist between Ly$\alpha$ equivalent width and the offset between Ly$\alpha$ and UV emission ($\Delta d_{\rm Ly\alpha}$) with a median $\Delta d_{\rm Ly\alpha} \sim 1$ kpc. This could be explained by Ly$\alpha$ radiative transfer process in both ISM and CGM. The results usher a new era of detailed analysis on high-$z$ LAEs with the JWST capability.

Orphan galaxies that have lost a large fraction of the dark matter subhaloes have often been invoked in semi-analytical as well as empirical models of galaxy formation. We run a mock cluster finder that mimics the optical cluster finding technique of the redMaPPer algorithm on a catalogue of galaxies with quenched star formation from one such empirical model, the UniverseMachine, and obtain the prevalence of orphan galaxies in these clusters as a function of their cluster-centric distance. We compare the fraction of orphan galaxies with the upper limits derived based on our prior observations of the weak lensing signals around satellite galaxies from SDSS redMaPPer clusters. Although the orphan fraction from the UniverseMachine is marginally consistent with the upper limits in the innermost regions of galaxy clusters spanning [0.1, 0.3] $h^{-1}$ Mpc, we observe that the orphan fractions substantially violate the upper limits in the outer regions of galaxy clusters beyond 0.3 $h^{-1}$ Mpc. We discuss the reasons, plausible improvements to the model and how observations can be used to constrain such models further.

Direct imaging searches for exoplanets around stars detect many spurious candidates that are in fact background field stars. To help distinguish these from genuine companions, multi-epoch astrometry can be used to identify a common proper motion with the host star. Although this is frequently done, many approaches lack an appropriate model for the motions of the background population, or do not use a statistical framework to properly quantify the results. Here we use Gaia astrometry combined with 2MASS photometry to model the parallax and proper motion distributions of field stars around exoplanet host stars as a function of candidate magnitude. We develop a likelihood-based method that compares the positions of a candidate at multiple epochs with the positions expected under both this field star model and a co-moving companion model. Our method propagates the covariances in the Gaia astrometry and the candidate positions. True companions are assumed to have long periods compared to the observational baseline, so we currently neglect orbital motion. We apply our method to a sample of 23 host stars with 263 candidates identified in the B-Star Exoplanet Abundance Study (BEAST) survey on VLT/SPHERE. We identify seven candidates in which the odds ratio favours the co-moving companion model by a factor of 100 or more. Most of these detections are based on only two or three epochs separated by less than three years, so further epochs should be obtained to reassess the companion probabilities. Our method is publicly available as an open-source python package from https://github.com/herzphi/compass to use with any data.

The SiO emissions are usually used to trace high-velocity outflow shocks in star-forming regions. However, several studies have found low-velocity and widespread SiO emissions not associated with outflows in molecular clouds. We aim to detect and characterize the SiO emissions in massive dense cores (MDCs), and explore the properties of the central sources of SiO emission. We present high-angular-resolution ($\sim$1.5$^{\prime\prime}$) observations of the SiO (5$-$4) line made with the Submillimeter Array towards a sample of 48 MDCs in the Cygnus-X star-forming complex. We studied the SiO emission structures, including their morphologies, kinematics, and energetics, and investigated their relationship with the evolution of the central sources. The SiO (5$-$4) emission is detected in 16 out of 48 MDCs. We identify 14 bipolar and 18 unipolar SiO (5$-$4) outflows associated with 29 dust condensations. Most outflows (24 out of 32) are associated with excess Spitzer 4.5 $\mu$m emissions. We also find diffuse low-velocity ($\Delta{v}$ $\le$ 1.2 km s$^{-1}$) SiO (5$-$4) emission closely surrounding the dust condensations in two MDCs, and suggest that it may originate from decelerated outflow shocks or large-scale shocks from global cloud collapse. We find that the SMA SiO (5$-$4) emission in MDCs is mostly associated with outflows. Probably due to the relatively high excitation of SiO (5$-$4) compared to SiO (2$-$1) and due to the spatial filtering effect, we do not detect large-scale low-velocity SiO (5$-$4) emission, but detect more compact low-velocity emission in close proximity to the dust condensations. We group the sources into different evolutionary stages based on the infrared emission, radio continuum emission, and gas temperature properties of the outflow central sources, and find that the 24 $\mu$m luminosity tends to increase with evolution.

Gamma-ray burst (GRB) 221009A produced the highest flux of gigaelectronvolt-teraelectronvolt ($\rm GeV-TeV$) photons ever observed, allowing the construction of a detailed $\rm TeV$ light curve. We focus on explaining the noticeable dip in the light curve around $2$-$5\ \rm s$ after the onset of $\rm TeV$ emission. We propose that Megaelectronvolt (MeV) photons from the prompt emission annihilate with $\rm TeV$ photons from the afterglow, producing an optical depth that obscures the $\rm TeV$ emission during this period. We develop a two-zone model accounting for the angles of MeV photons that can successfully reproduce the time delay between MeV and $\rm TeV$ photons, the peak optical depth over 3, and the rapid decline in optical depth. Our model supports $\rm MeV-TeV$ annihilation as the cause of the dip and provides reasonable constraints on the emission region parameters.

A recent study from the Horizon Run (HR5) cosmological simulation has predicted that galaxies with ${\rm log}~M_{\ast}/M_{\odot}\lesssim 10$ in the cosmic morning ($10\gtrsim z\gtrsim 4$) dominantly have disk-like morphology in the $\Lambda$CDM universe, which is driven by the tidal torque in the initial matter fluctuations. For a direct comparison with observation we identify a total of about $18,000$ James Webb Space Telescope (JWST) galaxies with ${\rm log}~M_{\ast}/M_{\odot}>9$ at $z=0.6-8.0$ utilizing deep JWST/NIRCam images of publicly released fields, including NEP-TDF, NGDEEP, CEERS, COSMOS, UDS, and SMACS J0723$-$7327. We estimate their stellar masses and photometric redshifts with the dispersion of $\sigma_{\rm NMAD}=0.007$ and outlier fraction of only about 5\%. We classify galaxies into three morphological types, `disks', `spheroids', and `irregulars', applying the same criteria used in the HR5 study. The morphological distribution of the JWST galaxies shows that disk galaxies account for $60-70\%$ at all redshift ranges. However, in the high-mass regime (${\rm log}~M_{\ast}/M_{\odot}\gtrsim11$), spheroidal morphology becomes the dominant type. This implies that mass growth of galaxies is accompanied with morphological transition from disks to spheroids. The fraction of irregulars is about 20\% or less at all mass and redshifts. All the trends in the morphology distribution are consistently found in the six JWST fields. These results are in close agreement with the results from the HR5 simulation, particularly confirming the prevalence of disk galaxies at small masses in the cosmic morning and noon.

Mid-infrared (mid-IR) gas-phase molecular bands are powerful diagnostics of the warm interstellar medium. We report the James Webb Space Telescope detection of the CO v=1-0 (4.4-5.0 um) and H2O nu2=1-0 (5.0-7.8um) ro-vibrational bands, both in absorption, toward the ``s2'' core in the southwest nucleus of the merging galaxy VV 114 E. All ro-vibrational CO lines up to J_low=33 (E_low~3000 K) are detected, as well as a forest of H2O lines up to 13_{0,13} (E_low~2600 K). The highest-excitation lines are blueshifted by ~180 km s^{-1} relative to the extended molecular cloud, which is traced by the rotational CO J=3-2 346 GHz line observed with the Atacama Large Millimeter/submillimeter Array. The bands also show absorption in a low-velocity component (blueshifted by ~30 km s^{-1}) with lower excitation. The analysis shows that the bands are observed against a continuum with effective temperature of T_bck~550 K extinguished with tau_6um^ext~ 2.5-3 (A_k~6.9-8.3 mag). The high-excitation CO and H2O lines are consistent with v=0 thermalization with T_rot~450 K and column densities of N_CO~(1.7-3.5)x10^{19} cm^{-2} and N_H2O~(1.5-3.0)x10^{19} cm$^{-2}$. Thermalization of the v=0 levels of H2O requires either an extreme density of n_H2>~10^9 cm^{-3}, or radiative excitation by the mid-IR field in a very compact (<1 pc) optically thick source emitting ~10^{10} L_sun. The latter alternative is favored, implying that the observed absorption probes the very early stages of a fully enshrouded active black hole (BH). On the basis of a simple model for BH growth and applying a lifetime constraint to the s2 core, an intermediate-mass BH (IMBH, M_BH~4.5x10^4 M_sun) accreting at super-Eddington rates is suggested, where the observed feedback has not yet been able to break through the natal cocoon.

The Vera C. Rubin Observatory will produce an unprecedented astronomical data set for studies of the deep and dynamic universe. Its Legacy Survey of Space and Time (LSST) will image the entire southern sky every three to four days and produce tens of petabytes of raw image data and associated calibration data over the course of the experiment's run. More than 20 terabytes of data must be stored every night, and annual campaigns to reprocess the entire dataset since the beginning of the survey will be conducted over ten years. The Production and Distributed Analysis (PanDA) system was evaluated by the Rubin Observatory Data Management team and selected to serve the Observatory's needs due to its demonstrated scalability and flexibility over the years, for its Directed Acyclic Graph (DAG) support, its support for multi-site processing, and its highly scalable complex workflows via the intelligent Data Delivery Service (iDDS). PanDA is also being evaluated for prompt processing where data must be processed within 60 seconds after image capture. This paper will briefly describe the Rubin Data Management system and its Data Facilities (DFs). Finally, it will describe in depth the work performed in order to integrate the PanDA system with the Rubin Observatory to be able to run the Rubin Science Pipelines using PanDA.

We undertook a search for new nearby dwarf galaxies outside the known groups in the Local Volume using the data on DESI Legacy Imaging Surveys. In a wide sky area of $\sim$5000 square degrees directed toward the Local Void, we found only 12 candidates to nearby low mass galaxies. Almost all of them are classified as irregular or transition type dwarfs. Additionally, we examined areas of the sky exposed with the Hyper Suprime Camera of the Subaru telescope ($\sim$700 square degrees) and found nine more candidates to nearby dwarfs. Finally, nine candidates to the Local Volume were selected by us from the Zaritsky's SMUDG catalog that contains 7070 ultra-diffuse objects automatically detected in the whole area of the DESI surveys. We estimated a fraction of quiescent dSph galaxies in the general cosmic field to be less than 10 percent.

3C 273 is one of the nearest high-luminosity quasars. Although classified as a blazar, 3C 273 also has some features in Seyferts, whose X-ray may originate from the corona. Since both jet and corona produce power-law spectra in X-ray, the spectrum cannot completely distinguish their contributions to 3C 273 in the low state. X-ray polarimetric observations provide the chance to constrain the X-ray radiation origin of 3C 273 in the low state. We perform general relativistic radiative transfer simulations with the code MONK to compute the X-ray polarization in 2-10 keV from the jets, sphere coronae, and slab coronae for 3C 273. We find that the radiation from the jet in 2-10 keV has a larger polarization degree than that of the corona: the polarization degree in 2-10 keV from the corona is unpolarized, while these are 4.1%-15.8% for the jet with a vertical or radial magnetic field and $\leq$5.0% for the jet with toroidal magnetic field. The X-ray polarization of the corona and jet is sensitive to optical depth and geometry, and the main driver for this dependence is the number of scatterings. These results show that X-ray polarization can effectively constrain the X-ray radiation origin of 3C 273 in the low state.

Known for their efficiency in analyzing large data sets, machine learning classifiers are widely used in wide-field sky surveys. The upcoming Vera C. Rubin Observatory Legacy of Time and Space Survey (LSST) will generate millions of alerts every night, enabling the discovery of large samples of rare events. Identifying such objects soon after explosion will be essential to study their evolution. This requires a machine learning framework that makes use of all available transient and contextual information. Using $\sim5400$ transients from the ZTF Bright Transient Survey as input data, we develop NEEDLE, a novel hybrid classifier to select for two rare classes with strong environmental preferences: superluminous supernovae (SLSNe) preferring dwarf galaxies, and tidal disruption events (TDEs) occurring in the centres of nucleated galaxies. The input data includes detection and reference images, photometric information from the alert packets, and host galaxy magnitudes from Pan-STARRS. Despite having only a few tens of examples of the rare classes, our average (best) completeness on an unseen test set reaches 77% (93%) for SLSNe and 72% (87%) for TDEs. This may still result in a large fraction of false positives for the rare transients, given the large class imbalance in real surveys. However, the goal of NEEDLE is to find good candidates for spectroscopic classification, rather than to select pure photometric samples. Our network is designed with LSST in mind and we expect performance to improve further with the higher resolution images and more accurate transient and host photometry that will be available from Rubin. Our system will be deployed as an annotator on the UK alert broker, Lasair, to provide predictions to the community in real time.

Astrochemical simulations are a powerful tool for revealing chemical evolution in the interstellar medium. Astrochemical calculations require efficient processing of large matrices for the chemical networks. The large chemical reaction networks often present bottlenecks for computation because of time derivatives of chemical abundances. We propose an efficient algorithm using a stoichiometry matrix approach in which this time-consuming part is expressed as a loop, unlike the algorithm used in previous studies. Since stoichiometry matrices are sparse in general, the performances of simulations with our algorithm depend on which sparse-matrix storage format is used. We conducted a performance comparison experiment using the common storage formats, including the coordinate (COO) format, the compressed column storage (CCS) format, the compressed row storage (CRS) format, and the Sliced ELLPACK (SELL) format. Experimental results showed that the simulations with the CRS format are the most suitable for astrochemical simulations and about three times faster than those with the algorithm used in previous studies. In addition, our algorithm significantly reduces not only the computation time but also the compilation time. We also explore the beneficial effects of parallelization and sparse-matrix reordering in these algorithms.

Redshift space distortions are an important probe of the growth of large-scale structure and for constraining cosmological parameters in general. As galaxy redshift surveys approach percent level precision in their observations of the two point clustering statistics, it is timely to review what effects baryons and associated processes such as feedback may have on small-scale clustering in redshift space. Contrary to previous studies in the literature, we show using the large-volume BAHAMAS hydrodynamic simulations that the effect of baryons can be as much as 1% in the k ~ 0.1 h/Mpc range for the monopole and 5% for quadrupole, and that this could rise to as much as 10% at k~10 h/Mpc in both measurements. For the halo power spectra, this difference can be as much 3-4% in the monopole on scales of 0.05 < k < 0.3 h/Mpc for 10^{13} M_sun/h haloes. We find that these deviations can be mitigated to the sub-percent level in the both the monopole and quadrupole up to k ~ 0.3 h/Mpc if the baryon corrected halo masses are used to calculate the redshift space power spectra. Finally, we use the cosmo-OWLS simulation suite to explore the changes in the redshift space power spectra with different feedback prescriptions, finding that there is a maximum of 15-20% difference between the redshift space monopole and quadrupole with and without baryons at k ~1-2 h/Mpc within these models.

As the primary fuel for star formation, molecular gas plays a key role in galaxy evolution. A number of techniques have been used for deriving the mass of molecular reservoirs in the early Universe (e.g., [CII]158$\mu$m, [CI], dust continuum), but the standard approach of CO-based estimates has been limited to a small number of galaxies due to the intrinsic faintness of the line. We present Jansky Very Large Array (JVLA) observations of the $z\sim8.31$ galaxy MACS0416_Y1, targeting CO(2-1) and rest-frame radio continuum emission, which result in upper limits on both quantities. Adding our continuum limit to the published far-infrared (FIR) spectral energy distribution (SED), we find a small non-thermal contribution to the FIR emission, a low dust mass ($\rm\log_{10}(M_D/M_{\odot})\sim5$), and an abnormally high dust temperature ($\rm T_D\gtrsim90K$) that may indicate a recent starburst. Assuming a low metallicity ($Z/Z_{\odot}\sim0.25$), we find evidence for $M_{\rm H_2,CO}\lesssim10^{10}$M$_{\odot}$, in agreement with previous [CII] investigations ($M_{\rm H_2,[CII]}\sim10^{9.6}$M$_{\odot}$). Upcoming JWST observations of this source will result in a precise determination of $Z$, enabling better constraints and an unprecedented view of the gaseous reservoir in this primordial starburst galaxy.

KASCADE-Grande, the extension of the multi-detector setup of KASCADE, was devoted to measure the properties of extensive air showers initiated by high-energy cosmic rays in the primary energy range of 1 PeV up to 1 EeV. The observations of the energy spectrum and mass composition of cosmic rays contribute with great detail to the understanding of the transition from galactic to extragalactic origin of cosmic rays, and furthermore to validate the properties of hadronic interaction models in the air shower development. Although the experiment is fully dismantled, the analysis of the entire KASCADE-Grande data set continues. We have recently investigated the impact of different post-LHC hadronic interaction models, QGSJETII-04, EPOS-LHC, Sibyll 2.3d, on air shower predictions in terms of the reconstructed spectra of heavy and light primary masses, including systematic uncertainties. In addition, the conversely discussed evolution of the muon content of high-energy air showers in the atmosphere is compared with the predictions of different interaction models. In this contribution, the latest results from the KASCADE-Grande measurements will be discussed.

Context. Transmission spectroscopy is one of the most powerful techniques to characterize transiting exoplanets since it allows to measure the abundance of the atomic and molecular species in the planetary atmosphere. However, the stellar lines can bias the determination of such abundances if their center-to-limb variations (CLVs) are not properly accounted for. Aims. This paper aims to show that three-dimensional (3D) radiation hydrodynamic models and non-local thermodynamic equilibrium (non-LTE) line formation are required for an accurate modeling of the stellar CLV of the Na I D$_1$ and K I resonance lines on transmission spectra. Methods. We model the CLV of the Na I D$_1$ and K I resonance lines in the Sun with 3D non-LTE radiative transfer. The synthetic spectra are compared to solar observations with high spatial and spectral resolution, including new data collected with the CRISP instrument at the Swedish 1-m Solar Telescope between $\mu=0.1$ and $\mu=1.0$. Results. Our 3D non-LTE modeling of the Na I D$_1$ resonance line at 5896 {\AA} and the K I 7699 {\AA} resonance line in the Sun is in good agreement with the observed CLV in the solar spectrum. The simulated CLV curve for a Jupiter-Sun system inferred with a 3D non-LTE analysis shows significant differences from that obtained from a 1D atmosphere. The latter tends to overestimate the amplitude of the transmission curve by a factor that is of the same order of magnitude as a planetary absorption depth (up to 0.2 %). Conclusions. In order to correctly characterize exoplanetary atmospheres, 3D non-LTE synthetic spectra should be used to estimate the stellar CLV effect in transmission spectra of solar-like planet hosts. The work will be extended to other lines and FGK-type stars, allowing synthetic high-resolution spectra to mitigate the stellar contamination of low-resolution planetary spectra, e.g. those from JWST.

Solar active regions contain a broad range of temperatures, with the thermal plasma distribution often observed to peak in the few millions of kelvin. Differential emission measure (DEM) analysis can allow instruments with diverse temperature responses to be used in concert to estimate this distribution. NuSTAR HXR observations are uniquely sensitive to the highest-temperature components of the corona, and thus extremely powerful for examining signatures of reconnection-driven heating. Here, we use NuSTAR diagnostics in combination with EUV and SXR observations (from SDO/AIA and Hinode/XRT) to construct DEMs over 170 distinct time intervals during a five-hour observation of an alternately flaring and quiet active region (NOAA designation AR 12712). This represents the first HXR study to examine the time evolution of the distribution of thermal plasma in an active region. During microflares, we find that the initial microflare-associated plasma heating is dominantly heating of material that is already relatively hot, followed later on by broader heating of initially-cooler material. During quiescent times, we show that the amount of extremely hot (>10 MK) material in this region is significantly (~3 orders of magnitude) less than that found in the quiescent active region observed in HXRs by FOXSI-2 (Ishikawa et al. 2017). This result implies there can be radically different high-temperature thermal distributions in different active regions, and strongly motivates future HXR DEM studies covering a large number of these regions.

Weak gravitational lensing simulations serve as indispensable tools for obtaining precise cosmological constraints. In particular, it is crucial to address the systematic uncertainties in theoretical predictions, given the rapid increase in galaxy numbers and the reduction in observational noise. Both on-the-fly and post-processing methods for constructing lensing light-cones encounter limitations due to the finite simulated volume, necessitating the replication of the simulation box to encompass the volume to high redshifts. To address this issue, our primary focus lies on investigating and quantifying the impact of box replication on the convergence power spectrum and higher-order moments of lensing fields. By combining the KS test with these statistics, we confirm that there is a probability exceeding 99\% to observe the significant statistical deviation from the correct measurements for all investigated special line-of-sight directions, e.g., x-axis direction. Additionally, we have developed a code that facilitates the identification of optimal viewing angles for the light-cone construction. This code has been made publicly accessible.

The splashback radius, coinciding with the minimum in the dark matter radial density gradient, is thought to be a universal definition of the edge of a dark matter halo. Observational methods to detect it have traced the dark matter using weak gravitational lensing or galaxy number counts. Recent attempts have also claimed the detection of a similar feature in Sunyaev-Zel'dovich (SZ) observations of the hot intracluster gas. Here, we use the FLAMINGO simulations to investigate whether a reflection of the splashback feature is predicted to occur in the cluster gas profiles. We find that the minimum in the gradient of the stacked 3D gas density and pressure profiles, and the maximum in the entropy profile, broadly align with the splashback feature though there are significant differences. While the dark matter splashback radius varies with specific mass accretion rate, in agreement with previous work, the radial position of the feature in the gas density is more sensitive to halo mass. In addition, we show that the feature is also present in projected 2D pseudo-observable profiles: emission measure (X-ray); Compton-$y$ (SZ) and surface mass density (weak lensing). We find that the latter traces the dark matter results reasonably well albeit the feature occurs at a slightly smaller radius. While results for the gas profiles are largely insensitive to accretion rate and various observable proxies for dynamical state, they do depend on the strength of the feedback processes.

Kuiper belt objects are thought to be formed at least a few million years after the formation of calcium-aluminium-rich inclusions, at a time when the $^{26}$Al isotope -- the major source of radiogenic heat in the early Solar System -- had significantly depleted. The internal structure of these objects is highly dependent on any additional source that can produce extra heat in addition to that produced by the remaining, long-lasting radioactive isotopes. In this paper, we explore how serpentinization, the hydration of silicate minerals, can contribute to the heat budget and to what extent it can modify the internal structure of large Kuiper belt objects. We find that the extent of restructuring depends very strongly on the start time of the formation process, the size of the object, and the starting ice-to-rock ratio. Serpentinization is able to restructure most of the interior of all objects in the whole size range (400-1200\,km) and ice-to-rock ratio range investigated if the process starts early, $\sim$3\,Myr after CAI formation, potentially leading to a predominantly serpentine core much earlier than previously thought ($\leq$5\,Myr vs. several tens of million years). While the ratio of serpentinized material gradually decreases with the increasing formation time, the increasing ice-to-rock ratio, and the increasing start time of planetesimal formation in the outer solar system, in the case of the largest objects a significant part of the interior will be serpentinized even if the formation starts relatively late, $\sim$5\,Myr after CAI formation. Therefore it is feasible that the interior of planetesimals may have contained a significant amount of serpentine, and in some cases, it could have been a dominant constituent, at the time of satellite-forming impacts.

The rotation state of small asteroids is affected in the long term by perturbing torques of gravitational and radiative origin (the YORP effect). Direct observational evidence of the YORP effect is the primary goal of our work. We carried out photometric observations of five near-Earth asteroids: (1862) Apollo, (2100) Ra-Shalom, (85989) 1999 JD6, (138852) 2000 WN10, and (161989) Cacus. Then we applied the light-curve inversion method to all available data to determine the spin state and a convex shape model for each of the five studied asteroids. In the case of (2100) Ra-Shalom, the analysis required that the spin-axis precession due to the solar gravitational torque also be included. We obtained two new detections of the YORP effect: (i) $(2.9 \pm 2.0)\times 10^{-9}\,\mathrm{rad\,d}^{-2}$ for (2100) Ra-Shalom, and (ii) $(5.5\pm 0.7)\times 10^{-8}\,\mathrm{rad\,d}^{-2}$ for (138852) 2000 WN10. The analysis of Ra-Shalom also reveals a precession of the spin axis with a precession constant $\sim 3000''\,\mathrm{yr}^{-1}$. This is the first such detection from Earth-bound photometric data. For the other two asteroids, we improved the accuracy of the previously reported YORP detection: (i) $(4.94 \pm 0.09)\times 10^{-8}\,\mathrm{rad\,d}^{-2}$ for (1862) Apollo, and (ii) $(1.86\pm 0.09)\times 10^{-8}\,\mathrm{rad\,d}^{-2}$ for (161989) Cacus. Despite the recent report of a detected YORP effect for (85989) 1999 JD6, we show that the model without YORP cannot be rejected statistically. Therefore, the detection of the YORP effect for this asteroid requires future observations. The spin-axis precession constant of Ra-Shalom determined from observations matches the theoretically expected value. The total number of asteroids with a YORP detection has increased to 12. In all cases, the rotation frequency increases in time.

Galactic outflows are believed to play a critical role in the evolution of galaxies by regulating their mass build-up and star formation. Theoretical models assumes bipolar shapes for the outflows that extends well into the circumgalctic medium (CGM), up to tens of kpc perpendicular to the galaxies. They have been directly observed in the local Universe in several individual galaxies, e.g., around the Milky Way and M82. At higher redshifts, cosmological simulations of galaxy formation predict an increase in the frequency and efficiency of galactic outflows due to the increasing star formation activity. Outflows are responsible for removing potential fuel for star formation from the galaxy, while at the same enriching the CGM and the intergalactic medium. These feedback processes, although incorporated as key elements of cosmological simulations, are still poorly constrained on CGM scales. Here we present an ultra-deep MUSE image of the mean MgII emission surrounding a sample of galaxies at z~1 that strongly suggests the presence of outflowing gas on physical scales of more than 10kpc. We find a strong dependence of the detected signal on the inclination of the central galaxy, with edge-on galaxies clearly showing enhanced MgII emission along the minor axis, while face-on galaxies display much weaker and more isotropic emission. We interpret these findings as supporting the idea that outflows typically have a bipolar cone geometry perpendicular to the galactic disk. We demonstrate that the signal is not dominated by a few outliers. After dividing the galaxy sample in subsamples by mass, the bipolar emission is only detected in galaxies with stellar mass $\mathrm{M_* \gtrsim 10^{9.5} M_\odot}$.

We study the robustness of the baryon acoustic oscillation (BAO) analysis to the underlying cosmological model. We focus on testing the standard BAO analysis that relies on the use of a template. These templates are constructed assuming a fixed fiducial cosmological model and used to extract the location of the acoustic peaks. Such ``compressed analysis'' had been shown to be unbiased when applied to the $\Lambda$CDM model and some of its extensions. However, it has not been known whether this type of analysis introduces biases in a wider range of cosmological models where the template may not fully capture relevant features in the BAO signal. In this study, we apply the compressed analysis to noiseless mock power spectra that are based on Horndeski models, a broad class of modified-gravity theories specified with eight additional free parameters. We study the precision and accuracy of the BAO peak-location extraction assuming DESI, DESI II, and MegaMapper survey specifications. We find that the bias in the extracted peak locations is negligible; for example, it is less than 10% of the statistical error for even the proposed future MegaMapper survey. Our findings indicate that the compressed BAO analysis is remarkably robust to the underlying cosmological model.

We explore the capability of measuring lensing signals in $LiteBIRD$ full-sky polarization maps. With a $30$ arcmin beam width and an impressively low polarization noise of $2.16\,\mu$K-arcmin, $LiteBIRD$ will be able to measure the full-sky polarization of the cosmic microwave background (CMB) very precisely. This unique sensitivity also enables the reconstruction of a nearly full-sky lensing map using only polarization data, even considering its limited capability to capture small-scale CMB anisotropies. In this paper, we investigate the ability to construct a full-sky lensing measurement in the presence of Galactic foregrounds, finding that several possible biases from Galactic foregrounds should be negligible after component separation by harmonic-space internal linear combination. We find that the signal-to-noise ratio of the lensing is approximately $40$ using only polarization data measured over $90\%$ of the sky. This achievement is comparable to $Planck$'s recent lensing measurement with both temperature and polarization and represents a four-fold improvement over $Planck$'s polarization-only lensing measurement. The $LiteBIRD$ lensing map will complement the $Planck$ lensing map and provide several opportunities for cross-correlation science, especially in the northern hemisphere.

We analyze a single-epoch Global mm-VLBI Array (GMVA) observation of the blazar BL Lacertae (BL Lac) at 86 GHz from April 2021. The participation of the upgraded, phased Northern Extended Millimetre Array (NOEMA) adds additional sensitivity to the GMVA, which has facilitated the imaging of BL Lac during an unprecedentedly strong $\gamma$-ray flare. We aim to explore the nature of the inner subparsec jet of BL Lac and the impact of the NOEMA participation in the observation. For the data reduction, we employed two advanced automatic pipelines: rPICARD for the flux density calibration as well as the model-agnostic signal stabilization and GPCAL for the antenna leakage calibration. The conventional hybrid imaging (CLEAN + amplitude and phase self-calibration) was applied to the calibrated visibilities to generate final VLBI images. We performed a ridge-line analysis and Gaussian model-fits on the final jet image to derive the jet parameters. In our data, the presence of NOEMA improves the image sensitivity by a factor of 2.5. The jet shows a clear wiggling structure within 0.4 mas from the core. Our ridge-line analysis suggests the presence of a helical jet structure (i.e., a sinusoidal pattern). Six circular Gaussian components were fitted to the inner jet region. We estimated an apparent brightness temperature of $\sim$3 $\times$ 10$^{12}$ K in the two innermost components. They are likely to be highly boosted by relativistic beaming effect. We find four significant polarized knots in the jet. Interestingly, two of them are located in the core region. Finally, we suggest a number of physical scenarios to interpret our results.

We estimate the efficiency of mitigating the lensing $B$-mode polarization, the so-called delensing, for the $LiteBIRD$ experiment with multiple external data sets of lensing-mass tracers. The current best bound on the tensor-to-scalar ratio, $r$, is limited by lensing rather than Galactic foregrounds. Delensing will be a critical step to improve sensitivity to $r$ as measurements of $r$ become more and more limited by lensing. In this paper, we extend the analysis of the recent $LiteBIRD$ forecast paper to include multiple mass tracers, i.e., the CMB lensing maps from $LiteBIRD$ and CMB-S4-like experiment, cosmic infrared background, and galaxy number density from $Euclid$- and LSST-like survey. We find that multi-tracer delensing will further improve the constraint on $r$ by about $20\%$. In $LiteBIRD$, the residual Galactic foregrounds also significantly contribute to uncertainties of the $B$-modes, and delensing becomes more important if the residual foregrounds are further reduced by an improved component separation method.

The Local Void is one of the nearest large voids, located at a distance of 23 Mpc. It lies largely behind the Galactic Bulge and is therefore extremely difficult to observe. We use HI 21 cm emission observations from the SARAO MeerKAT Galactic Plane Survey (SMGPS) to study the Local Void and its surroundings over the Galactic longitude range 329$^{\circ}< \ell <$ 55$^{\circ}$, Galactic latitude $|b| <$ 1.5$^{\circ}$, and redshift $cz <$ 7500 km/s. We have detected 291 galaxies to median rms sensitivity of 0.44 mJy per beam per 44 km/s channel. We find 17 galaxies deep inside the Void, 96 at the border of the Void, while the remaining 178 galaxies are in average density environments. The extent of the Void is ~ 58 Mpc. It is severely under-dense for the longitude range 350$^{\circ}< \ell <$ 35$^{\circ}$ up to redshift $z <$ 4500 km/s. The galaxies in the Void tend to have \HI masses that are lower (by approximately 0.25 dex) than their average density counterparts. We find several potential candidates for small groups of galaxies, of which two groups (with 3 members and 5 members) in the Void show signs of filamentary substructure within the Void.

Molecular abundances in protoplanetary disks are highly sensitive to the local physical conditions, including gas temperature, gas density, radiation field, and dust properties. Often multiple factors are intertwined, impacting the abundances of both simple and complex species. We present a new approach to understanding these chemical and physical interdependencies using machine learning. Specifically we explore the case of CO modeled under the conditions of a generic disk and build an explanatory regression model to study the dependence of CO spatial density on the gas density, gas temperature, cosmic ray ionization rate, X-ray ionization rate, and UV flux. Our findings indicate that combinations of parameters play a surprisingly powerful role in regulating CO compared to any singular physical parameter. Moreover, in general, we find the conditions in the disk are destructive toward CO. CO depletion is further enhanced in an increased cosmic ray environment and in disks with higher initial C/O ratios. These dependencies uncovered by our new approach are consistent with previous studies, which are more modeling intensive and computationally expensive. Our work thus shows that machine learning can be a powerful tool not only for creating efficient predictive models, but also for enabling a deeper understanding of complex chemical processes.

We briefly review the phenomenon of long secondary periods (LSPs) in red giants, and the LSP variable stars classification introduced in the All-Sky Automated Survey for Supernovae (ASAS-SN) variable star catalog; they are red giant Long Period Variables (LPVs) in which their LSP variability is significantly greater than their pulsational variability. We then describe and discuss the results of a period and amplitude analysis of a random sample of 35 LSP variables in the ASAS-SN catalog, using ASAS-SN data and the AAVSO VStar time-series analysis software. The pulsation period and amplitude, and LSP, all increase with increasing luminosity or size of the star, as expected. The behavior of the LSP amplitude is more complicated; it appears to be larger in moderate-luminosity stars, and smaller in low- and high-luminosity stars. In particular, it is relatively small in a sample of 27 Mira stars, analyzed separately using AAVSO visual data. These results are discussed in the context of the current model for the LSP phenomenon, namely that it is caused by eclipses of the red giant star by a dust-enshrouded companion.

Theories with more than one scalar field often exhibit phase transitions producing potentially detectable gravitational wave (GW) signal. In this work we study the semi-annihilating $\mathbb{Z}_3$ dark matter model, whose dark sector comprises an inert doublet and a complex singlet, and assess its prospects in future GW detectors. Without imposing limits from requirement of providing a viable dark matter candidate, i.e. taking into account only other experimental and theoretical constraints, we find that the first order phase transition in this model can be strong enough to lead to a detectable signal. However, direct detection and the dark matter thermal relic density constraint calculated with the state-of-the-art method including the impact of early kinetic decoupling, very strongly limit the parameter space of the model explaining all of dark matter and providing observable GW peak amplitude. Extending the analysis to underabundant dark matter thus reveals region with detectable GWs from a single-step or multi-step phase transition.

An explicit realistic model featuring a supercool phase transition, which allows us to explain the background of gravitational waves recently detected by pulsar timing arrays, is constructed. In this model the phase transition corresponds to radiative symmetry breaking (and mass generation) in a dark sector featuring a dark photon associated with the broken symmetry. The completion of the transition is ensured by a non-minimal coupling between gravity and the order parameter and fast reheating occurs thanks to a preheating phase. Finally, it is also shown that the model leads to primordial black hole production.

The gravitational waves emitted (some time) after two black holes merge are well described by the theory of linear perturbations on a spacetime characterized by the mass and spin of the remnant. However, in the very early stages right after merger, both the mass and spin are changing. In this work we explore, in a set up based on Vaidya's spacetime, the dynamical consequences of a change of mass in the spacetime due to the accretion of null matter (for example, gravitational waves). We show that accretion imprints time-dependent frequencies and amplitude to a ringdown waveform, and we show how to model accurately this effect in certain regimes. We also comment on the direct emission of gravitational waves due to perturbations in the in--falling matter, which is of relevance for black holes embedded in astrophysical environments.

Recent advancements in gravitational wave astronomy have seen the application of convolutional neural networks (CNNs) in signal detection from compact binary coalescences. This study presents a comparative analysis of two CNN architectures: one-dimensional (1D) and two-dimensional (2D) along with an ensemble model combining both. We trained these models to detect gravitational wave signals from binary black hole (BBH) mergers, neutron star-black hole (NSBH) mergers, and binary neutron star (BNS) mergers within real detector noise. Our investigation entailed a comprehensive evaluation of the detection performance of each model type across different signal classes. To understand the models' decision-making processes, we employed feature map visualization and attribution analysis. The findings revealed that while the 1D model showed superior performance in detecting BBH signals, the 2D model excelled in identifying NSBH and BNS signals. Notably, the ensemble model outperformed both individual models across all signal types, demonstrating enhanced detection capabilities. Additionally, input feature visualization indicated distinct areas of focus in the data for the 1D and 2D models, emphasizing the effectiveness of their combination.

We study sub-GeV dark matter (DM) particles that may annihilate or decay into Standard Model (SM) particles producing an electron-positron cascade that results in positronium bound state formation after energy losses. This comprises an exotic injection component in the Milky Way that leaves an imprint in the 511 keV photon line due to the decay of positronium into two photons. In this work, we use $\sim16$~yr of SPI spectrometer data from the INTEGRAL satellite to constrain DM properties. We include three major novelties in our study: i) we account for positron diffusion and propagation, as well as positron losses due to annihilation in flight and other energy losses, ii) we include the free electron density suppression away from the Galactic plane and iii) we derive limits for decaying DM for the first time with SPI data. We show that the predicted longitude and latitude profiles change significantly for different DM masses, contrary to what has previously been assumed. In addition, we find that the limits derived from this new set of SPI data are the strongest on sub-GeV DM to date across almost the entire DM mass range considered (from MeV to a few GeV), excluding cross-sections down to $10^{-32}$ cm$^3$ s$^{-1} \, \, (\text{for} \,\, m_{\chi}\sim1 \,\text{MeV}) \lesssim \langle \sigma v\rangle \lesssim10^{-26}$ cm$^3$ s$^{-1} \, \, (m_{\chi}\sim5\,\text{GeV})$ and lifetimes up to $10^{29}\, \textrm{s} \, (m_{\chi}\sim1\,\text{MeV})\lesssim \tau \lesssim 10^{27}\,\textrm{s}$ ($m_{\chi}\sim5$~GeV), whilst considering best-fit cosmic ray (CR) propagation and diffusion parameters. These limits surpass even the most stringent complementary cosmological and astrophysical limits over most of the mass range considered.

The Chinese Space Station Telescope (abbreviated as CSST) is a future advanced space telescope. Real-time identification of galaxy and nebula/star cluster (abbreviated as NSC) images is of great value during CSST survey. While recent research on celestial object recognition has progressed, the rapid and efficient identification of high-resolution local celestial images remains challenging. In this study, we conducted galaxy and NSC image classification research using deep learning methods based on data from the Hubble Space Telescope. We built a Local Celestial Image Dataset and designed a deep learning model named HR-CelestialNet for classifying images of the galaxy and NSC. HR-CelestialNet achieved an accuracy of 89.09% on the testing set, outperforming models such as AlexNet, VGGNet and ResNet, while demonstrating faster recognition speeds. Furthermore, we investigated the factors influencing CSST image quality and evaluated the generalization ability of HR-CelestialNet on the blurry image dataset, demonstrating its robustness to low image quality. The proposed method can enable real-time identification of celestial images during CSST survey mission.

This short contributions summarizes a couple of recent results to test dark matter properties with galactic dynamics. First, I will present the impact in rotation curves from solitonic structures expected at the center of galaxies for ultralight bosonic dark matter. As a result, one can claim that masses of the order $m_{\rm DM}\lesssim 10^{-21}$eV are in tension with data. Second, I will discuss how the dark matter medium properties change the way a `probe' interacts with the halo. I will focus on dynamical friction and show how it is modified in the case of degenerate fermions. This result may be used to address the Fornax timing problem. I hope that this contribution represents an inspiration to continue exploring other ideas in this direction of using galactic dynamics to tell apart different dark matter models.

In this paper, we revisit the experimental constraints on the multipolar dark matter that has derivative coupling to the visible sector mediated by the Standard Model photon. The momentum dependent interaction enables them to be captured efficiently within massive celestial bodies boosted by their steep gravitational potential. This phenomena makes compact celestial bodies as an efficient target to probe such type of dark matter candidates. We demonstrate that a synergy of the updated direct detection results from DarkSide-50 and LUX-ZEPLIN together with IceCube bounds on high energy solar neutrinos from dark matter capture disfavour the viable parameter space of the dipolar dark matter scenario. Whereas, for the anapole dark matter scenario, a narrow window survives that lies within the reach of prospective heating signals due to the capture of dark matter at cold neutron stars.

Sequential ionization of fullerene cluster ions (C$_{60}$)$_{n}^{+}$ within multiply-charged helium nanodroplets leads to the intriguing phenomenon of forming and stabilizing doubly- and triply-charged fullerene oligomers. Surprisingly, we have detected (C$_{60}$)$_{2}^{2+}$ and (C$_{60}$)$_{2}^{3+}$, indicating that dimers, rather than the previously established pentamers and dodecamers, are the smallest fullerene cluster sizes capable of stabilizing two and even three charges. This remarkable resilience against Coulomb explosion is achieved through efficient cooling within the superfluid environment of helium nanodroplets, and a sequential ionization scheme that populates covalently bound or physisorbed fullerene dimers. Calculations support the stability of four differently bonded (C$_{60}$)$_{2}^{2+}$ and (C$_{60}$)$_{2}^{3+}$ isomers and predict a low Coulomb barrier (<0.4 eV) preventing even dissociation of cold van der Waals complexes.

Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black holes and neutron star magnetospheres, where accretion-powered jets and pulsar winds are expected to be enriched with such pair plasmas. Their behaviour is quite different from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components and their role in the dynamics of such compact objects is believed to be fundamental. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies which are rather limited. We present first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN's Super Proton Synchrotron (SPS) accelerator. The produced pair beams have a volume that fills multiple Debye spheres and are thus able to sustain collective plasma oscillations. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations.