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X-Ray Telescopes Could Study Exoplanets Too Exoplanets are often discovered using the transit method (over three quarters of those discovered have been found this way.) The same transit technique can be used to study them, often revealing detail about their atmosphere. The observations are typically made in visible light or infrared but a new paper suggests X-rays may be useful too. Stellar wind interactions with the planet’s atmosphere for example would lead to X-ray emissions revealing information about the atmosphere. As we further our exploration of exoplanets we develop our understanding of our own Solar System and ultimately, the origins of life in the Universe. Read More →

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Life Needs Black Holes to Survive Life is rare, and it requires exactly the right environmental mix to establish itself. And there’s one surprising contributor to that perfect mix: gigantic black holes. Life requires a certain combination of elements to make itself possible: hydrogen, nitrogen, carbon, oxygen, phosphorus, and sulfur. Hydrogen has been hanging around the universe since the first few minutes of the big bang, but the other elements only come from fusion processes inside of stars. Galaxies need several generations of stellar lives and deaths before a solar system like our own can be possible. But left to its own devices, star formationRead More →

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In: arXiv

Gas permeability and mechanical properties of dust grain aggregates at hyper- and zero-gravity Holly L. Capelo, Jean-David Bod’enan, Martin Jutzi, Jonas K"uhn, Romain Cerubini, Bernhard Jost, Linus St"ockli, Stefano Spadaccia, Clemence Herny, Bastian Gundlach, G"unter Kargl, Cl’ement Surville, Lucio Mayer, Maria Sch"onb"achler, Nicolas Thomas, Antoine Pommerol arXiv:2408.12631v1 Announce Type: new Abstract: Particle-particle and particle-gas processes significantly impact planetary precursors such as dust aggregates and planetesimals. We investigate gas permeability ($kappa$) in 12 granular samples, mimicking planetesimal dust regoliths. Using parabolic flights, this study assesses how gravitational compression — and lack thereof — influences gas permeation, impacting the equilibrium state of low-gravity objects. Transitioning between micro-Read More →

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The JWST/NIRISS Deep Spectroscopic Survey for Young Brown Dwarfs and Free-Floating Planets Adam B. Langeveld, Aleks Scholz, Koraljka Muv{z}i’c, Ray Jayawardhana, Daniel Capela, Lo"ic Albert, Ren’e Doyon, Laura Flagg, Matthew de Furio, Doug Johnstone, David Lafr`eniere, Michael Meyer arXiv:2408.12639v1 Announce Type: new Abstract: The discovery and characterization of free-floating planetary-mass objects (FFPMOs) is fundamental to our understanding of star and planet formation. Here we report results from an extremely deep spectroscopic survey of the young star cluster NGC1333 using NIRISS WFSS on the James Webb Space Telescope. The survey is photometrically complete to K~21, and includes useful spectra for objects as faint as K~20.5. TheRead More →

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Multi-iron subpopulations in Liller 1 from high resolution H-band spectroscopy C. Fanelli, L. Origlia, R. M. Rich, F. R. Ferraro, D. A. Alvarez Garay, L. Chiappino, B. Lanzoni, C. Pallanca, C. Crociati, E. Dalessandro arXiv:2408.12649v1 Announce Type: new Abstract: We present a high resolution chemical study of a representative sample of 21 luminous giant stars of Liller~1, a complex stellar system in the Galactic bulge, based on H band spectra acquired with the Near InfraRed Spectrograph at KeckII. 15 stars turn out to have a subsolar iron abundance and enhanced [$alpha$/Fe] and [Al/Fe], likely old that formed early and quickly from gas mainly enriched byRead More →

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White Dwarf-Black Hole Binary Progenitors of Low Redshift Gamma-ray Bursts Nicole M. Lloyd-Ronning, Jarrett L. Johnson, Phoebe R. Upton Sanderbeck, Makana Silva, Roseanne M. Cheng arXiv:2408.12654v1 Announce Type: new Abstract: Although there is strong evidence that many long GRBs are associated with the collapse of a massive star, tantalizing results in recent years have upended the direct association of {em all} long GRBs with massive stars. In particular, kilonova signals in some long GRB light curves as well as a suggested uptick in the rate density of long GRBs at low redshifts (deviating significantly from the star formation rate) suggest that compact object mergers mayRead More →

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A candidate dark matter deficient dwarf galaxy in the Fornax cluster identified through overluminous star clusters Aaron J. Romanowsky, Enrique Cabrera, Steven R. Janssens arXiv:2408.12663v1 Announce Type: new Abstract: Two low surface brightness (LSB) dwarf galaxies were identified recently as having little or no dark matter (DM), provoking widespread interest in their formation histories. These galaxies also host populous systems of star clusters that are on average larger and more luminous than typical globular clusters (GCs). We report an initial attempt to identify new candidate DM-deficient dwarfs via their unusual GC systems. Using a large catalog of LSB galaxies from the Dark Energy Survey, weRead More →

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In: arXiv

NEXUS: the North ecliptic pole EXtragalactic Unified Survey Yue Shen, Ming-Yang Zhuang, Junyao Li, Adam J. Burgasser, Xiaohui Fan, Jenny E. Greene, Gautham Narayan, Alice E. Shapley, Fengwu Sun, Feige Wang, Qian Yang arXiv:2408.12713v1 Announce Type: new Abstract: NEXUS is a JWST Multi-Cycle (Cycles 3-5; 368 primary hrs) GO Treasury imaging and spectroscopic survey around the North Ecliptic Pole. It contains two overlapping tiers. The Wide tier ($sim 400~{rm arcmin}^2$) performs NIRCam/WFSS 2.4-5 micron grism spectroscopy with three epochs over 3 years (final continuum ${rm S/N/pixel>3}$ at F444W$3}$ at F200W$lesssim 27/29$). All epochs have simultaneous multi-band NIRCam and MIRI imaging ($5sigma$ final depths of $simRead More →

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In: arXiv

Comparing Gaia, NED and SIMBAD source classifications in nearby galaxies J. Hales, P. Barmby arXiv:2408.12717v1 Announce Type: new Abstract: Gaia Data Release 3 (DR3) provides the first classifications for the sources in Gaia’s all-sky database. Most Gaia sources are stars in the Milky Way, but DR3 also contains many sources that belong to nearby galaxies, as well as background galaxies and quasars. In this work, we compare the Gaia classifications from the Discrete Source Classifier (CU8-DSC) module to the more detailed and heterogeneous classifications in NED and/or SIMBAD for sources with sky positions within twice the Holmberg radius of nearby galaxies. Matching these catalogues givesRead More →

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In: arXiv

A Comparison of the X-ray Polarimetric Properties of Stellar and Supermassive Black Holes M. Lynne Saade, Philip Kaaret, Ioannis Liodakis, Steven R. Ehlert arXiv:2408.12746v1 Announce Type: new Abstract: X-ray polarization provides a new way to probe accretion geometry in black hole systems. If the accretion geometry of black holes is similar regardless of mass, we should expect the same to be true of their polarization properties. We compare the polarimetric properties of all non-blazar black holes observed with IXPE. We find that their polarization properties are very similar, particularly in the hard state, where the corona dominates. This tentatively supports the idea that stellar andRead More →

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Variable Stars in M31 Stellar Clusters from the Panchromatic Hubble Andromeda Treasury Richard Smith, Avi Patel, Monika D. Soraisam, Puragra Guhathakurta, Pranav Tadepalli, Sally Zhu, Joseph Liu, L’eo Girardi, L. Clifton Johnson, Sagnick Mukherjee, Knut A. G. Olsen, Benjamin F. Williams arXiv:2408.12765v1 Announce Type: new Abstract: Variable stars in stellar clusters can offer key constraints on stellar evolution and pulsation models, utilising estimates of host cluster properties to constrain stellar physical parameters. We present a catalogue of 86 luminous (F814WarXiv:2408.12765v1 Announce Type: new Abstract: Variable stars in stellar clusters can offer key constraints on stellar evolution and pulsation models, utilising estimates of host cluster propertiesRead More →

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In: arXiv

An automated method for finding the most distant quasars Lena Lenz, Daniel J. Mortlock, Boris Leistedt, Rhys Barnett, Paul C. Hewett arXiv:2408.12770v1 Announce Type: new Abstract: Upcoming surveys such as Euclid, the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) and the Nancy Grace Roman Telescope (Roman) will detect hundreds of high-redshift (z > 7) quasars, but distinguishing them from the billions of other sources in these catalogues represents a significant data analysis challenge. We address this problem by extending existing selection methods by using both i) Bayesian model comparison on measured fluxes and ii) a likelihood-based goodness-of-fit test on images, whichRead More →

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In: arXiv

Broad-band X-ray spectral and timing properties of the accreting millisecond X-ray pulsar IGR J17498$-$2921 during the 2023 outburst Zhaosheng Li, L. Kuiper, Y. Y. Pan, M. Falanga, J. Poutanen, Y. P. Chen, R. X. Xu, M. Y. Ge, Y. Huang, L. M. Song, S. Zhang, F. J. Lu, S. N. Zhang arXiv:2408.12786v1 Announce Type: new Abstract: We report on the broadband spectral and timing properties of the accreting millisecond X-ray pulsar IGR J17498$-$2921 during its April 2023 outburst using data from NICER (1$-$10 keV), NuSTAR (3$-$79 keV), Insight-HXMT (2$-$150 keV), and INTEGRAL (30$-$150 keV). We detect significant 401 Hz pulsations across the 0.5$-$150 keV band.Read More →

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The Evolution of Protostellar Outflow Opening Angles and the Implications for the Growth of Protostars Michael M. Dunham, Ian W. Stephens, Philip C. Myers, Tyler L. Bourke, H’ector G. Arce, Riwaj Pokhrel, Jaime E. Pineda, Joseph Vargas arXiv:2408.12788v1 Announce Type: new Abstract: We use 1-4″ (300-1200 au) resolution 12CO(2-1) data from the MASSES (Mass Assembly of Stellar Systems and their Evolution with the SMA) project to measure the projected opening angles of 46 protostellar outflows in the Perseus Molecular Cloud, 37 of which are measured with sufficiently high confidence to use in further analysis. We find that there is a statistically significant difference in theRead More →

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The FAST Core Array Peng Jiang, Rurong Chen, Hengqian Gan, Jinghai Sun, Boqin Zhu, Hui Li, Weiwei Zhu, Jingwen Wu, Xuelei Chen, Haiyan Zhang, Tao An arXiv:2408.12826v1 Announce Type: new Abstract: The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) Core Array is a proposed extension of FAST, integrating 24 secondary 40-m antennas implanted within 5 km of the FAST site. This original array design will combine the unprecedented sensitivity of FAST with a high angular resolution (4.3″ at a frequency of 1.4 GHz), thereby exceeding the capabilities at similar frequencies of next-generation arrays such as the Square Kilometre Array Phase 1 or the next-generation Very LargeRead More →

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Exploring Active Galactic Nuclei and Little Red Dots with the Obelisk simulation M. Volonteri, M. Trebitsch, Y. Dubois, J. E. Greene, C. -A. Dong-Paez, M. Habouzit, A. Lupi, Y. Ma, R. S. Beckmann, P. Dayal arXiv:2408.12854v1 Announce Type: new Abstract: The James Webb Space telescope has discovered an abundant population of broad line emitters, typical signposts for Active Galactic Nuclei (AGN). Many of these sources have red colors and a compact appearance that has led to naming them `Little Red Dots’. In this paper we develop a detailed framework to estimate the photometry of AGN embedded in galaxies extracted from the Obelisk cosmological simulation toRead More →

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FRB Line-of-sight Ionization Measurement From Lightcone AAOmega Mapping Survey: the First Data Release Yuxin Huang, Sunil Simha, Ilya Khrykin, Khee-Gan Lee, J. Xavier Prochaska, Nicolas Tejos, Keith Bannister, Jason Barrios, John Chisholm, Jeff Cooke, Adam Deller, Marcin Glowacki, Lachlan Marnoch, Ryan Shannon, Jielai Zhang arXiv:2408.12864v1 Announce Type: new Abstract: This paper presents the first public data release (DR1) of the FRB Line-of-sight Ionization Measurement From Lightcone AAOmega Mapping (FLIMFLAM) Survey, a wide field spectroscopic survey targeted on the fields of 10 precisely localized Fast Radio Bursts (FRBs). DR1 encompasses spectroscopic data for 10,468 galaxy redshifts across 10 FRBs fields with z10 Mpc scales), `Narrow’, (several-arcminuteRead More →

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In: arXiv

Performance evaluation of the high-voltage CMOS active pixel sensor AstroPix for gamma-ray space telescopes Yusuke Suda, Regina Caputo, Amanda L. Steinhebel, Nicolas Striebig, Manoj Jadhav, Yasushi Fukazawa, Masaki Hashizume, Carolyn Kierans, Richard Leys, Jessica Metcalfe, Michela Negro, Ivan Peri’c, Jeremy S. Perkins, Taylor Shin, Hiroyasu Tajima, Daniel Violette, Norito Nakano arXiv:2408.12891v1 Announce Type: new Abstract: AstroPix is a novel monolithic high-voltage CMOS active pixel sensor proposed for next generation medium-energy gamma-ray observatories like the All-sky Medium Energy Gamma-ray Observatory eXplorer (AMEGO-X). For AMEGO-X AstroPix must maintain a power consumption of less than $1.5~rm{mW/{cm}^2}$ while having a pixel pitch of up to $500~rm{mu m}$. We developedRead More →

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In: arXiv

The Velocity Aberration Effect of the CSST Main Survey Camera Hui-Mei Feng, Zi-Huang Cao, Man I Lam, Ran Li, Hao Tian, Xin Zhang, Peng Wei, Xin-Feng Li, Wei Wang, Hugh R. A. Jones, Mao-Yuan Liu, Chao Liu arXiv:2408.12929v1 Announce Type: new Abstract: In this study, we conducted simulations to find the geometric aberrations expected for images taken by the Main Survey Camera (MSC) of the Chinese Space Station Telescope (CSST) due to its motion. As anticipated by previous work, our findings indicate that the geometric distortion of light impacts the focal plane’s apparent scale, with a more pronounced influence as the size of the focalRead More →

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Hydrodynamical shear mixing in subsonic boundary layers and its role in the thermonuclear explosion of classical novae Marco Bellomo, Steven N. Shore, Jordi Jos’e arXiv:2408.12937v1 Announce Type: new Abstract: The transition zone between the white dwarf (WD) envelope and a circumstellar accretion disk in classical novae, the boundary layer, is a region of strong dissipation and intense vorticity. In this strongly sheared layer, the hydrogen-rich accreted gas is expected to mix with the underlying WD outermost layers so the conditions for the onset of the thermonuclear runaway (TNR) in classical nova will be different from the the standard treatment of the onset and subsequent mixing.Read More →