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Spatially resolving the AGB star V3 in the metal-poor globular cluster 47 Tuc with VLTI/GRAVITY⋆ Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-18 K. Ohnaka, G. Weigelt, K.-H. Hofmann, D. Schertl
Context. Mass loss at the asymptotic giant branch (AGB) plays an important role not only in the final fates of stars, but also in the chemical evolution of galaxies. Nevertheless, the metallicity effects on AGB mass loss are not yet fully understood.Aims. We present spatially resolved observations of an AGB star, V3, in the metal-poor globular cluster 47 Tuc (NGC 104).Methods. The AGB star 47 Tuc V3
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Gaia’s brightest very metal-poor (VMP) stars Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-15 Akshara Viswanathan, Else Starkenburg, Tadafumi Matsuno, Kim A. Venn, Nicolas F. Martin, Nicolas Longeard, Anke Ardern-Arentsen, Raymond G. Carlberg, Sébastien Fabbro, Georges Kordopatis, Martin Montelius, Federico Sestito, Zhen Yuan
Context. Gaia DR3 has offered the scientific community a remarkable dataset of approximately one million spectra acquired with the radial velocity spectrometer (RVS) in the calcium II triplet region, which is well suited to identify very metal-poor (VMP) stars. However, over 40% of these spectra have no released parameters by Gaia’s GSP-Spec pipeline in the domain of VMP stars, whereas VMP stars are
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The SRG/eROSITA All-Sky Survey Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-13 A. Liu, E. Bulbul, M. Kluge, V. Ghirardini, X. Zhang, J. S. Sanders, E. Artis, Y. E. Bahar, F. Balzer, M. Brüggen, N. Clerc, J. Comparat, C. Garrel, E. Gatuzz, S. Grandis, G. Lamer, A. Merloni, K. Migkas, K. Nandra, P. Predehl, M. E. Ramos-Ceja, T. H. Reiprich, R. Seppi, S. Zelmer
Superclusters of galaxies mark the large-scale overdense regions in the Universe. Superclusters provide an ideal environment to study structure formation and to search for the emission of the intergalactic medium such as cosmic filaments and WHIM. In this work, we present the largest-to-date catalog of X-ray-selected superclusters identified in the first SRG/eROSITA All-Sky Survey (eRASS1). By applying
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Evidence of extended [CII] and dust emission in local dwarf galaxies Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-13 M. Romano, D. Donevski, Junais Junais, A. Nanni, M. Ginolfi, G. C. Jones, I. Shivaei, G. Lorenzon, M. Hamed, D. Salak, P. Sawant
Aims. The evolution of dwarf galaxies is dramatically affected by gaseous and dusty outflows, which can easily deprive their interstellar medium of the material needed for the formation of new stars, simultaneously enriching their surrounding circumgalactic medium (CGM). In this Letter, we present the first evidence of extended [CII] 158 μm line and dust continuum emission in local dwarf galaxies hosting
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The astrophysical parameters of chemically peculiar stars from automatic methods Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-13 E. Paunzen
Context. The chemically peculiar (CP) stars of the upper main sequence are excellent astrophysical laboratories for investigating the diffusion, mass loss, rotational mixing, and pulsation in the presence and absence of a stable local magnetic field. For this, we need a homogeneous set of parameters, such as effective temperature (Teff) and surface gravity (log g), to locate the stars in the Hertzsprung-Russell
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A newborn active galactic nucleus in a star-forming galaxy Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-13 P. Arévalo, E. López-Navas, M. L. Martínez-Aldama, P. Lira, S. Bernal, P. Sánchez-Sáez, M. Salvato, L. Hernández-García, C. Ricci, A. Merloni, M. Krumpe
Aims. We report on the finding of a newborn active galactic nucleus (AGN), based on the observation of current AGN activity in a galaxy previously classified as non-active. We subsequently characterize the AGN’s evolution.Methods. Black hole ignition event candidates were selected from a parent sample of spectrally classified non-active galaxies (2 394 312 objects), which currently show optical flux
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Four new eclipsing accreting ultracompact white dwarf binaries found with the Zwicky Transient Facility Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-13 J. M. Khalil, J. van Roestel, E. C. Bellm, J. S. Bloom, R. Dekany, A. J. Drake, M. J. Graham, S. L. Groom, S. R. Kulkarni, R. R. Laher, A. A. Mahabal, T. Prince, R. Riddle
Context. Accreting ultracompact white dwarf binaries contain a white dwarf that is accreting from a degenerate object. They have orbital periods shorter than 65 min.Aims. We report the discovery and the orbital period of four new eclipsing accreting ultracompact white dwarf binaries found using the Zwicky Transient Facility (ZTF) and discuss their photometric properties.Methods. We searched through
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Possible Hycean conditions in the sub-Neptune TOI-270 d Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-07 Måns Holmberg, Nikku Madhusudhan
The JWST has ushered in a new era in atmospheric characterisations of temperate low-mass exoplanets with recent detections of carbon-bearing molecules in the candidate Hycean world K2-18 b. We investigated JWST observations of the TOI-270 system, with two sub-Neptunes simultaneously transiting the nearby M dwarf during the visit. We report our atmospheric characterisation of the outer planet TOI-270
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TeV flaring activity of the AGN PKS 0625–354 in November 2018 Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-06 F. Aharonian, F. Ait Benkhali, J. Aschersleben, H. Ashkar, M. Backes, A. Baktash, V. Barbosa Martins, J. Barnard, R. Batzofin, Y. Becherini, D. Berge, K. Bernlöhr, B. Bi, M. Böttcher, C. Boisson, J. Bolmont, M. de Bony de Lavergne, J. Borowska, F. Bradascio, M. Breuhaus, R. Brose, A. Brown, F. Brun, B. Bruno, T. Bulik, C. Burger-Scheidlin, T. Bylund, S. Caroff, S. Casanova, R. Cecil, J. Celic, M. Cerruti
Most γ-ray detected active galactic nuclei are blazars with one of their relativistic jets pointing towards the Earth. Only a few objects belong to the class of radio galaxies or misaligned blazars. Here, we investigate the nature of the object PKS 0625−354, its γ-ray flux and spectral variability and its broad-band spectral emission with observations from H.E.S.S., Fermi-LAT, Swift-XRT, and UVOT taken
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Lithium-rich Cepheid V470 Cas⋆ Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-06 R. P. Martin, V. V. Kovtyukh, S. M. Andrievsky, S. A. Korotin
Aims. In this Letter, we report the discovery of a new lithium-rich yellow supergiant star – the Cepheid V470 Cas – that has a high lithium abundance, log A(Li) = 3.29. This is highly unusual for supergiant stars. V470 Cas is joining a very select group of lithium-rich Cepheids, with only nine members known to date in our Galaxy.Methods. For the analysis of our high-resolution echelle spectrum obtained
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Revealing the characteristics of the dark GRB 150309A: Dust extinguished or high-z?⋆ Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-04 A. J. Castro-Tirado, R. Gupta, S. B. Pandey, A. Nicuesa Guelbenzu, S. Eikenberry, K. Ackley, A. Gerarts, A. F. Valeev, S. Jeong, I. H. Park, S. R. Oates, B.-B. Zhang, R. Sánchez-Ramírez, A. Martín-Carrillo, J. C. Tello, M. Jelínek, Y.-D. Hu, R. Cunniffe, V. V. Sokolov, S. Guziy, P. Ferrero, M. D. Caballero-García, A. K. Ror, A. Aryan, M. A. Castro Tirado, E. Fernández-García, M. Gritsevich, I. Olivares
Context. Dark gamma-ray bursts (GRBs) constitute a significant fraction of the GRB population. In this paper, we present a multi-wavelength analysis (both prompt emission and afterglow) of an intense (3.98 × 10−5 erg cm−2 using Fermi-Gamma-Ray Burst Monitor) two-episodic GRB 150309A observed early on until ∼114 days post burst. Despite the strong gamma-ray emission, no optical afterglow was detected
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3C 273 host galaxy with Hubble Space Telescope coronagraphy⋆ Astron. Astrophys. (IF 6.5) Pub Date : 2024-03-01 Bin B. Ren, Kevin Fogarty, John H. Debes, Eileen T. Meyer, Youbin Mo, Dimitri Mawet, Marshall D. Perrin, Patrick M. Ogle, Johannes Sahlmann
The close-in regions of bright quasars’ host galaxies have been difficult to image due to the overwhelming light coming from quasars. With coronagraphic observations in visible light using the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope, we removed 3C 273 quasar light using color-matching reference stars. The observations revealed the host galaxy from 60″ to 0.″2 with
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Angular momentum and chemical transport by azimuthal magnetorotational instability in radiative stellar interiors Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-29 Domenico G. Meduri, Laurène Jouve, François Lignières
Context. The transport of angular momentum and chemical elements within evolving stars remains poorly understood. Asteroseismic and spectroscopic observations of low-mass main sequence stars and red giants reveal that their radiative cores rotate orders of magnitude slower than classical predictions from stellar evolution models and that the abundances of their surface light elements are too small
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Discovery of the first olivine-dominated A-type asteroid family Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-29 M. Galinier, M. Delbo, C. Avdellidou, L. Galluccio
The classical theory of differentiation states that due to the heat generated by the decay of radioactive elements, some asteroids form an iron core, an olivine-rich mantle, and a crust. The collisional breakup of these differentiated bodies is expected to lead to exposed mantle fragments, creating families of newly-formed asteroids. Among these new objects, some are expected to show an olivine-rich
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Cosmic Vine: A z = 3.44 large-scale structure hosting massive quiescent galaxies Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-29 Shuowen Jin, Nikolaj B. Sillassen, Georgios E. Magdis, Malte Brinch, Marko Shuntov, Gabriel Brammer, Raphael Gobat, Francesco Valentino, Adam C. Carnall, Minju Lee, Aswin P. Vijayan, Steven Gillman, Vasily Kokorev, Aurélien Le Bail, Thomas R. Greve, Bitten Gullberg, Katriona M. L. Gould, Sune Toft
We report the discovery of a large-scale structure at z = 3.44 revealed by JWST data in the Extended Groth Strip (EGS) field. This structure, called the Cosmic Vine, consists of 20 galaxies with spectroscopic redshifts at 3.43 < z < 3.45 and six galaxy overdensities (4 − 7σ) with consistent photometric redshifts, making up a vine-like structure extending over a ∼4 × 0.2 pMpc2 area. The two most massive
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Meteoroid rotation and quasi-periodic brightness variation of meteor light curves Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-28 Salvatore Mancuso, Dario Barghini, Daniele Gardiol
Meteor light curves are sometimes known to display flickering: rapid, quasi-periodic variations in brightness. This effect is generally attributed to the rotational modulation of the ablation rate, which is caused by the time-varying cross section area presented by a nonspherical rotating meteoroid to the oncoming airflow. In this work we investigate the effects that the rotation of a meteoroid of
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How to Turn Jets into Cylinders near Supermassive Black Holes in 3D General Relativistic Magnetohydrodynamic Simulations Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-28 Valeriia Rohoza, Aretaios Lalakos, Max Paik, Koushik Chatterjee, Matthew Liska, Alexander Tchekhovskoy, Ore Gottlieb
Accreting supermassive black holes (SMBHs) produce highly magnetized relativistic jets that tend to collimate gradually as they propagate outward. However, recent radio interferometric observations of the 3C 84 galaxy reveal a stunning, cylindrical jet already at several hundred SMBH gravitational radii, r ≳ 350r g. We explore how such extreme collimation emerges via a suite of 3D general relativistic
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Probing the Dark Matter density with gravitational waves from super-massive binary black holes J. Cosmol. Astropart. Phys. (IF 6.4) Pub Date : 2024-02-28 Anish Ghoshal, Alessandro Strumia
Supermassive black hole binaries source gravitational waves measured by Pulsar Timing Arrays. The frequency spectrum of this stochastic background is predicted more precisely than its amplitude. We argue that Dark Matter friction can suppress the spectrum around nHz frequencies, where it is measured, allowing to derive robust and significant bounds on the Dark Matter density, which, in turn, controls
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Minimal Inert Doublet benchmark for dark matter and the baryon asymmetry J. Cosmol. Astropart. Phys. (IF 6.4) Pub Date : 2024-02-28 María Dias Astros, Sven Fabian, Florian Goertz
In this article we discuss a minimal extension of the Inert Doublet Model (IDM) with an effective CP-violating D=6 operator, involving the inert Higgs and weak gauge bosons, that can lift it to a fully realistic setup for creating the baryon asymmetry of the Universe (BAU). Avoiding the need to stick to an explicit completion, we investigate the potential of such an operator to give rise to the measured
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Dark matter vorticity and velocity dispersion from truncated Dyson-Schwinger equations J. Cosmol. Astropart. Phys. (IF 6.4) Pub Date : 2024-02-28 Alaric Erschfeld, Stefan Floerchinger
Large-scale structure formation is studied in a kinetic theory approach, extending the standard perfect pressureless fluid description for dark matter by including the velocity dispersion tensor as a dynamical degree of freedom. The evolution of power spectra for density, velocity and velocity dispersion degrees of freedom is investigated in a non-perturbative approximation scheme based on the Dyson-Schwinger
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The NANOGrav 12.5 yr Data Set: Search for Gravitational Wave Memory Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Gabriella Agazie, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Harsha Blumer, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Timothy Dolch, Brendan Drachler,
We present the results of a Bayesian search for gravitational wave (GW) memory in the NANOGrav 12.5 yr data set. We find no convincing evidence for any gravitational wave memory signals in this data set. We find a Bayes factor of 2.8 in favor of a model that includes a memory signal and common spatially uncorrelated red noise (CURN) compared to a model including only a CURN. However, further investigation
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Discovery of Astrometric Accelerations by Dark Companions in the Globular Cluster ω Centauri Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Imants Platais, Johannes Sahlmann, Léo Girardi, Vera Kozhurina-Platais, Sebastian Kamann, Dimitri Pourbaix, Florence Wragg, Gerard Lemson, Arik Mitschang
We present results from the search for astrometric accelerations of stars in ω Centauri using 13 yr of regularly scheduled Hubble Space Telescope WFC3/UVIS calibration observations in the cluster core. The high-precision astrometry of ∼160,000 sources was searched for significant deviations from linear proper motion. This led to the discovery of four cluster members and one foreground field star with
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Thermal Effects of Ambipolar Diffusion during the Gravitational Collapse of a Radiative Cooling Filament Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Mahmoud Gholipour
In this study, we consider the effects of ambipolar diffusion during the gravitational collapse of a radiative cooling filamentary molecular cloud. Two separate configurations of magnetic field, i.e., axial and toroidal, are considered in the presence of the ambipolar diffusion for a radiative cooling filament. These configurations lead to two different formulations of the problem. The filament is
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Prospects for Probing the Interaction between Dark Energy and Dark Matter Using Gravitational-wave Dark Sirens with Neutron Star Tidal Deformation Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Tian-Nuo Li, Shang-Jie Jin, Hai-Li Li, Jing-Fei Zhang, Xin Zhang
Gravitational wave (GW) standard siren observations provide a rather useful tool to explore the evolution of the Universe. In this work, we wish to investigate whether dark sirens with neutron star (NS) deformation from third-generation GW detectors could help probe the interaction between dark energy and dark matter. We simulate the GW dark sirens of four detection strategies based on 3 yr observation
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Surveying the Giant H ii Regions of the Milky Way with SOFIA. VI. NGC 3603 Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 James M. De Buizer, Wanggi Lim, Nicole Karnath, James T. Radomski
We present our sixth set of results from our mid-infrared imaging survey of Milky Way Giant H ii regions with our detailed analysis of NGC 3603, the most luminous giant H ii (GH ii) region in the Galaxy. We used imaging data from the FORCAST instrument on the Stratospheric Observatory For Infrared Astronomy (SOFIA) at 20 and 37 μm, which mapped the central ∼8.′5 × 8.′5 infrared-emitting area of NGC
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The Near-infrared Extinction Law at High and Low Galactic Latitudes Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Robert E. Butler, Samir Salim
The Milky Way dust extinction curve in the near-infrared (NIR) follows a power-law form, but the value of the slope, β NIR, is debated. Systematic variations in the slope of the Milky Way UV extinction curve are known to be correlated with variations in the optical slope (through R V ), but whether such a dependence extends to the NIR is unclear. Finally, because of low dust column densities, the NIR
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PROVABGS: The Probabilistic Stellar Mass Function of the BGS One-percent Survey Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 ChangHoon Hahn, Jessica Nicole Aguilar, Shadab Alam, Steven Ahlen, David Brooks, Shaun Cole, Axel de la Macorra, Peter Doel, Andreu A. Font-Ribera, Jaime E. Forero-Romero, Satya Gontcho A Gontcho, Klaus Honscheid, Song Huang, Theodore Kisner, Anthony Kremin, Martin Landriau, Marc Manera, Aaron Meisner, Ramon Miquel, John Moustakas, Jundan Nie, Claire Poppett, Graziano Rossi, Amélie Saintonge, Eusebio
We present the probabilistic stellar mass function (pSMF) of galaxies in the DESI Bright Galaxy Survey (BGS), observed during the One-percent Survey. The One-percent Survey was one of DESI’s survey validation programs conducted from 2021 April to May, before the start of the main survey. It used the same target selection and similar observing strategy as the main survey and successfully observed the
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Galaxies Going Bananas: Inferring the 3D Geometry of High-redshift Galaxies with JWST-CEERS Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Viraj Pandya, Haowen Zhang, Marc Huertas-Company, Kartheik G. Iyer, Elizabeth McGrath, Guillermo Barro, Steven L. Finkelstein, Martin Kümmel, William G. Hartley, Henry C. Ferguson, Jeyhan S. Kartaltepe, Joel Primack, Avishai Dekel, Sandra M. Faber, David C. Koo, Greg L. Bryan, Rachel S. Somerville, Ricardo O. Amorín, Pablo Arrabal Haro, Micaela B. Bagley, Eric F. Bell, Emmanuel Bertin, Luca Costantin
The 3D geometries of high-redshift galaxies remain poorly understood. We build a differentiable Bayesian model and use Hamiltonian Monte Carlo to efficiently and robustly infer the 3D shapes of star-forming galaxies in James Webb Space Telescope Cosmic Evolution Early Release Science observations with logM*/M⊙=9.0–10.5 at z = 0.5–8.0. We reproduce previous results from the Hubble Space Telescope Cosmic
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The Magellan M2FS Spectroscopic Survey of High-redshift Galaxies: The Brightest Lyman-break Galaxies at z ∼ 6 Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Shuqi Fu, Linhua Jiang, Yuanhang Ning, Weiyang Liu, Zhiwei Pan
We present a study of a sample of 45 spectroscopically confirmed, UV luminous galaxies at z ∼ 6. They were selected as bright Lyman-break galaxies (LBGs) using deep multiband optical images in more than 2 deg2 of the sky, and subsequently identified via their strong Lyα emission. The majority of these LBGs span an absolute UV magnitude range from −22.0 to −20.5 mag with Lyα equivalent width (EW) between
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Radial Distribution of Electron Quasi-thermal Noise in the Outer Heliosphere Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Yi-Lun Li, Ling Chen, Jin Wu De
Voyager 1 and 2 are only the two spacecraft that have arrived and passed through the heliospheric boundaries. Based on the plasma data from the Voyager 2 spacecraft, the electron quasi-thermal noise (QTN) is investigated by using of the electron population model consisting of a core with Maxwellian distribution and a halo with kappa distribution. The power spectra of the electron QTN is calculated
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The Remarkable Predictive Power of Infrared Data of Blazars Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 P. Giommi, N. Sahakyan, D. Israyelyan, M. Manvelyan
Blazars are the brightest and most abundant persistent sources in the extragalactic γ-ray sky. Due to their significance, they are often observed across various energy bands, where the data of which can be used to explore potential correlations between emission at different energies, yielding valuable insights into the emission processes of their powerful jets. In this study we utilized IR data at
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COOL-LAMPS. VI. Lens Model and New Constraints on the Properties of COOL J1241+2219, a Bright z = 5 Lyman Break Galaxy and its z = 1 Cluster Lens Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Maxwell Klein, Keren Sharon, Kate Napier, Michael D. Gladders, Gourav Khullar, Matthew Bayliss, Håkon Dahle, M. Riley Owens, Antony Stark, Sasha Brownsberger, Keunho J. Kim, Nicole Kuchta, Guillaume Mahler, Grace Smith, Ryan Walker, Katya Gozman, Michael N. Martinez, Owen S. Matthews Acuña, Kaiya Merz, Jorge A. Sanchez, Daniel J. Kavin Stein, Ezra O. Sukay, Kiyan Tavangar
We present a strong lensing analysis of COOL J1241+2219, the brightest known gravitationally lensed galaxy at z ≥ 5, based on new multiband Hubble Space Telescope (HST) imaging data. The lensed galaxy has a redshift of z = 5.043, placing it shortly after the end of the “Epoch of Reionization,” and an AB magnitude z AB = 20.47 mag (Khullar et al.). As such, it serves as a touchstone for future research
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Simple Model for Temporal Variations of Hα Spectrum by an Eruptive Filament from a Superflare on a Solar-type Star Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Kai Ikuta, Kazunari Shibata
Flares are intense explosions on the solar and stellar surfaces, and solar flares are sometimes accompanied by filament or prominence eruptions. Recently, a large filament eruption associated with a superflare on a solar-type star EK Dra was discovered for the first time. The absorption of the Hα spectrum initially exhibited a blueshift with the velocity of 510 km s−1, and decelerated in time probably
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Dust around Massive Stars Is Agnostic to Galactic Environment: New Insights from PHAT/BEAST Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Christina Willecke Lindberg, Claire E. Murray, Julianne J. Dalcanton, J. E. G. Peek, Karl D. Gordon
Resolving the environments of massive stars is crucial for understanding their formation mechanisms and their impact on galaxy evolution. An important open question is whether massive stars found in diffuse regions outside spiral arms formed in situ or migrated there after forming in denser environments. To address this question, we use multiresolution measurements of extinction in the Andromeda galaxy
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Very High-energy (>50 GeV) Gamma-Ray Flux Variability of Bright Fermi Blazars Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Vaidehi S. Paliya
Understanding the high-energy emission processes and variability patterns are two of the most challenging research problems associated with relativistic jets. In particular, the long-term (months to years) flux variability at very high energies (VHE >50 GeV) has remained an unexplored domain so far. This is possibly due to the decreased sensitivity of the Fermi Large Area Telescope (LAT) above a few
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A Transition Discovered in the Subcritical Regime of 1A 0535+262 Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Hua Xiao, Long Ji
We present NICER observations of the accreting X-ray pulsar 1A 0535+262 during its faint state (≲6 × 1036 erg s−1), observed in several type I and type II outbursts. We discovered a transition of temporal and spectral properties around the luminosity L t = 3.3 × 1035 erg s−1, below which spectra are relatively soft and the pulse profiles have only a narrow peak. The spectra are harder and a secondary
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Cosmic Reionization on Computers: Statistics, Physical Properties, and Environments of Lyman Limit Systems at z ∼ 6 Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Jiawen Fan, Hanjue Zhu, Camille Avestruz, Nickolay Y. Gnedin
Lyman limit systems (LLSs) are dense hydrogen clouds with high enough H i column densities to absorb Lyman continuum photons emitted from distant quasars. Their high column densities imply an origin in dense environments; however, the statistics and distribution of LLSs at high redshifts still remain uncertain. In this paper, we use self-consistent radiative transfer cosmological simulations from the
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An Excess of Active Galactic Nuclei Triggered by Galaxy Mergers in MaNGA Galaxies of Stellar Mass ∼1011 M ⊙ Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Julia M. Comerford, Rebecca Nevin, James Negus, R. Scott Barrows, Michael Eracleous, Francisco Müller-Sánchez, Namrata Roy, Aaron Stemo, Thaisa Storchi-Bergmann, Dominika Wylezalek
To facilitate new studies of galaxy-merger-driven fueling of active galactic nuclei (AGNs), we present a catalog of 387 AGNs that we have identified in the final population of over 10,000 z < 0.15 galaxies observed by the Sloan Digital Sky Survey-IV (SDSS-IV) integral field spectroscopy survey Mapping Nearby Galaxies at Apache Point Observatory (MaNGA). We selected the AGNs via mid-infrared Wide-field
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A Massive Quiescent Galaxy in a Group Environment at z = 4.53 Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 Takumi Kakimoto, Masayuki Tanaka, Masato Onodera, Rhythm Shimakawa, Po-Feng Wu, Katriona M. L. Gould, Kei Ito, Shuowen Jin, Mariko Kubo, Tomoko L. Suzuki, Sune Toft, Francesco Valentino, Kiyoto Yabe
We report on the spectroscopic confirmation of a massive quiescent galaxy at z spec = 4.53 in the COSMOS field. The object was first identified as a galaxy with suppressed star formation at z phot ∼ 4.65 from the COSMOS2020 catalog. The follow-up spectroscopy with Keck/MOSFIRE in the K band reveals faint [O ii] emission and the Balmer break, indicative of evolved stellar populations. We fit the spectral
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On the Possibility of an Upper Limit on Magnetically Induced Radius Inflation in Low-mass Stars Astrophys. J. (IF 4.9) Pub Date : 2024-02-28 J. MacDonald, D. J. Mullan
The radii of low-mass stars are observed to be inflated above standard model predictions, especially in magnetically active stars. Typically, the empirical relative radius inflations ΔR/R are ≤10% but in (rare) cases may be ≥20%. Our magneto-convective stellar models have already replicated many empirical ΔR/R values. Here, we ask: is there any theoretical upper limit on the amount of such inflation
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Ubiquitous broad-line emission and the relation between ionized gas outflows and Lyman continuum escape in Green Pea galaxies Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-27 R. O. Amorín, M. Rodríguez-Henríquez, V. Fernández, J. M. Vílchez, R. Marques-Chaves, D. Schaerer, Y. I. Izotov, V. Firpo, N. Guseva, A. E. Jaskot, L. Komarova, D. Muñoz-Vergara, M. S. Oey, O. Bait, C. Carr, J. Chisholm, H. Ferguson, S. R. Flury, M. Giavalisco, M. J. Hayes, A. Henry, Z. Ji, W. King, F. Leclercq, G. Östlin, L. Pentericci, A. Saldana-Lopez, T. X. Thuan, M. Trebitsch, B. Wang, G. Worseck
We report observational evidence of highly turbulent ionized gas kinematics in a sample of 20 Lyman continuum (LyC) emitters (LCEs) at low redshift (z ∼ 0.3). Detailed Gaussian modeling of optical emission line profiles in high-dispersion spectra consistently shows that both bright recombination and collisionally excited lines can be fitted as one or two narrow components with intrinsic velocity dispersion
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Constraints on the evolution of the Triton atmosphere from occultations: 1989–2022 Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-27 B. Sicardy, A. Tej, A. R. Gomes-Júnior, F. D. Romanov, T. Bertrand, N. M. Ashok, E. Lellouch, B. E. Morgado, M. Assafin, J. Desmars, J. I. B. Camargo, Y. Kilic, J. L. Ortiz, R. Vieira-Martins, F. Braga-Ribas, J. P. Ninan, B. C. Bhatt, S. Pramod Kumar, V. Swain, S. Sharma, A. Saha, D. K. Ojha, G. Pawar, S. Deshmukh, A. Deshpande, S. Ganesh, J. K. Jain, S. K. Mathew, H. Kumar, V. Bhalerao, G. C. Anupama
Context. In about 2000, the south pole of Triton experienced an extreme summer solstice that occurs every ∼650 years, when the subsolar latitude reached about 50°S. Bracketing this epoch, a few occultations probed the Triton atmosphere in 1989, 1995, 1997, 2008, and 2017. A recent ground-based stellar occultation observed on 6 October 2022 provides a new measurement of the atmospheric pressure on Triton
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A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE): Impact of Galaxies on the Circumgalactic Medium Metal Enrichment at z > 6 Using the JWST and VLT Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-27 Siwei Zou, Zheng Cai, Feige Wang, Xiaohui Fan, Jaclyn B. Champagne, Joseph F. Hennawi, Jan-Torge Schindler, Emanuele Paolo Farina, Jinyi Yang, Kohei Inayoshi, Eduardo Bañados, Sarah E. I. Bosman, Zihao Li, Xiaojing Lin, Yunjing Wu, Fengwu Sun, Ziyi Guo, Girish Kulkuarni, Mélanie Habouzit, Stephane Charlot, Jacopo Chevallard, Thomas Connor, Anna-Christina Eilers, Linhua Jiang, Xiangyu Jin, Koki Kakiichi
We characterize the multiphase circumgalactic medium (CGM) and galaxy properties at z = 6.0–6.5 in four quasar fields from the James Webb Space Telescope A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE) program. We use the Very Large Telescope/X-shooter spectra of quasar J0305–3150 to identify one new metal absorber at z = 6.2713 with multiple transitions (O i, Mg ii, Fe ii,
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Optical Appearance of Eccentric Tidal Disruption Events Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-27 Fangyi (Fitz) Hu, Daniel J. Price, Ilya Mandel
Stars approaching supermassive black holes can be tidally disrupted. Despite being expected to emit X-rays, tidal disruption events (TDEs) have been largely observed in optical bands, which is poorly understood. In this Letter, we simulate the tidal disruption of a 1 M ⊙ main-sequence star on an eccentric (e = 0.95) orbit with a periapsis distance 1 or 5 times smaller than the tidal radius (β = 1 or
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The Very Early Soft X-Ray Plateau of GRB 230307A: Signature of an Evolving Radiative Efficiency in Magnetar Wind Dissipation? Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-27 Shu-Qing Zhong, Long Li, Di Xiao, Hui Sun, Bin-Bin Zhang, Zi-Gao Dai
Very recently, a particularly long gamma-ray burst (GRB) 230307A was reported and proposed to originate from a compact binary merger based on its host galaxy property, kilonova, and heavy elements. More intriguingly, a very early plateau followed by a rapid decline in the soft X-ray band was detected in its light curve by the Lobster Eye Imager for Astronomy, indicating strong evidence of the existence
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Deconstructing Photospheric Spectral Lines in Solar and Stellar Flares Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Aaron J. Monson, Mihalis Mathioudakis, Adam F. Kowalski
During solar flares, spectral lines formed in the photosphere have been shown to exhibit changes to their profiles despite the challenges of energy transfer to these depths. Recent work has shown that deep-forming spectral lines are subject to significant contributions from regions above the photosphere throughout the flaring period, resulting in a composite emergent intensity profile from multiple
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Tidal Migration of Exoplanets around M Dwarfs: Frequency-dependent Tidal Dissipation Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Samantha C. Wu, Janosz W. Dewberry, Jim Fuller
The orbital architectures of short-period exoplanet systems are shaped by tidal dissipation in their host stars. For low-mass M dwarfs whose dynamical tidal response comprises a dense spectrum of inertial modes at low frequencies, resolving the frequency dependence of tidal dissipation is crucial to capturing the effect of tides on planetary orbits throughout the evolutionary stages of the host star
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Zero Metallicity with Zero CPU Hours: Masses of the First Stars on the Laptop Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 James Gurian, Donghui Jeong, Boyuan Liu
We develop an analytic model for the mass of the first stars forming in the centers of primordial gas clouds as a function of host halo mass, redshift, and degree of rotation. The model is based on the estimation of key timescales determining the following three processes: the collapse of the gas cloud, the accretion onto the protostellar core, and the radiative feedback of the protostellar core. The
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Detection of Asymmetry in the Narrow Fe Kα Emission Line in MCG-5-23-16 with Chandra Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Victor Liu, Abderahmen Zoghbi, Jon M. Miller
Iron Kα (Fe Kα) emission is observed ubiquitously in active galactic nuclei (AGN), and it is a powerful probe of their circumnuclear environment. Examinations of the emission line play a pivotal role in understanding the disk geometry surrounding black holes. It has been suggested that the torus and the broad-line region (BLR) are the origins of emission. However, there is no universal location for
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Clouds and Seasonality on Terrestrial Planets with Varying Rotation Rates Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Daniel A. Williams, Xuan Ji, Paul Corlies, Juan M. Lora
Using an idealized climate model incorporating seasonal forcing, we investigate the impact of rotation rate on the abundance of clouds on an Earth-like aquaplanet, and the resulting impacts upon albedo and seasonality. We show that the cloud distribution varies significantly with season, depending strongly on the rotation rate, and is well explained by the large-scale circulation and atmospheric state
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Chondrule Survivability in the Solar Nebula Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Tetsuo Taki, Shigeru Wakita
The lifetime of millimeter-sized dust grains, such as chondrules, in the nominal solar nebula model is limited to ∼105 yr, due to an inward drift driven by gas drag. However, isotopic and petrological studies of primitive meteorites indicate a discrepancy of ≳106 yr between the formation time of chondrules and that of chondritic parent bodies. Therefore, chondrules should survive for ≳106 yr in the
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Influence of Ionization on the Polytropic Index of the Solar Atmosphere within Local Thermodynamic Equilibrium Approximation Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Albert M. Varonov, Todor M. Mishonov
An initial theoretical attempt to explain the observed decrease of the polytropic/adiabatic index γ in the solar corona has been accomplished. The chemical reactions of the ionization–recombination processes in local thermodynamic equilibrium (LTE) of a solar plasma cocktail containing heavy elements are found to cause 1.1 < γ ≤ 5/3 in the quiet solar atmosphere. It is also shown that the quiet solar
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Dwarf–Dwarf Interactions Can Both Trigger and Quench Star Formation Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Erin Kado-Fong, Azia Robinson, Kristina Nyland, Jenny E. Greene, Katherine A. Suess, Sabrina Stierwalt, Rachael Beaton
It is exceedingly rare to find quiescent low-mass galaxies in the field at low redshift. UGC 5205 is an example of such a quenched field dwarf (M ⋆ ∼ 3 × 108 M ⊙). Despite a wealth of cold gas (M HI ∼ 3.5 × 108 M ⊙) and UV emission that indicates significant star formation in the past few hundred megayears, there is no detection of Hα emission—star formation in the last ∼10 Myr—across the face of the
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Global Chemical Transport on Hot Jupiters: Insights from the 2D VULCAN Photochemical Model Astrophys. J. (IF 4.9) Pub Date : 2024-02-27 Shang-Min Tsai, Vivien Parmentier, João M. Mendonça, Xianyu Tan, Russell Deitrick, Mark Hammond, Arjun B. Savel, Xi Zhang, Raymond T. Pierrehumbert, Edward W. Schwieterman
The atmospheric dynamics of tidally locked hot Jupiters is characterized by strong equatorial winds. Understanding the interaction between global circulation and chemistry is crucial in atmospheric studies and interpreting observations. Two-dimensional (2D) photochemical transport models shed light on how the atmospheric composition depends on circulation. In this paper, we introduce the 2D photochemical
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Disentangling the origin of chemical differences using GHOST Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-26 C. Saffe, P. Miquelarena, J. Alacoria, E. Martioli, M. Flores, M. Jaque Arancibia, R. Angeloni, E. Jofré, J. Yana Galarza, E. González, A. Collado
Aims. We explore different scenarios to explain the chemical difference found in the remarkable giant-giant binary system HD 138202 + CD−30 12303. For the first time, we suggest how to distinguish these scenarios by taking advantage of the extensive convective envelopes of giant stars.Methods. We carried out a high-precision determination of stellar parameters and abundances by applying a full line-by-line
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FR0 jets and recollimation-induced instabilities Astron. Astrophys. (IF 6.5) Pub Date : 2024-02-26 A. Costa, G. Bodo, F. Tavecchio, P. Rossi, A. Capetti, S. Massaglia, A. Sciaccaluga, R. D. Baldi, G. Giovannini
Context. The recently discovered population of faint Fanaroff-Riley type 0 (FR0) radio galaxies has been interpreted as the extension to low power of the classical FRI sources. Their radio emission appears to be concentrated in very compact parsec scale cores, any extended emission is very weak or absent, and very-long-baseline interferometry (VLBI) observations show that jets are already mildly or
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Lyman Continuum Leakers in the AstroSat Ultraviolet Deep Field: Extreme-ultraviolet Emitters at the Cosmic Noon Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-26 Suraj Dhiwar, Kanak Saha, Soumil Maulick, Brent M. Smith, Chayan Mondal, Harry I. Teplitz, Marc Rafelski, Rogier A. Windhorst
We report the direct detection of Lyman continuum (LyC) emission from nine galaxies and one active galactic nucleus at z ∼ 1.1–1.6 in the GOODS-North field using deep observations from the Ultraviolet Imaging Telescope (UVIT) on board AstroSat. The absolute escape fraction of the sources estimated from the far-ultraviolet and Hα-line luminosities using Monte Carlo analysis of two intergalactic medium
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Discovery of Magnetically Guided Metal Accretion onto a Polluted White Dwarf Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-26 Stefano Bagnulo, Jay Farihi, John D. Landstreet, Colin P. Folsom
Dynamically active planetary systems orbit a significant fraction of white dwarf stars. These stars often exhibit surface metals accreted from debris disks, which are detected through infrared excess or transiting structures. However, the full journey of a planetesimal from star-grazing orbit to final dissolution in the host star is poorly understood. Here, we report the discovery that the cool metal-polluted
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Classification of Enhanced Geoeffectiveness Resulting from High-speed Solar Wind Streams Compressing Slower Interplanetary Coronal Mass Ejections Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-26 Stephan G. Heinemann, Chaitanya Sishtla, Simon Good, Maxime Grandin, Jens Pomoell
High-speed solar wind streams (HSSs) interact with the preceding ambient solar wind to form stream interaction regions (SIRs), which are a primary source of recurrent geomagnetic storms. However, HSSs may also encounter and subsequently interact with interplanetary coronal mass ejections (ICMEs). In particular, the impact of the interaction between slower ICMEs and faster HSSs represents an unexplored
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Roaring to Softly Whispering: X-Ray Emission after ∼3.7 yr at the Location of the Transient AT2018cow and Implications for Accretion-powered Scenarios* * Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-02-26 Giulia Migliori, R. Margutti, B. D. Metzger, R. Chornock, C. Vignali, D. Brethauer, D. L. Coppejans, T. Maccarone, L. Rivera Sandoval, J. S. Bright, T. Laskar, D. Milisavljevic, E. Berger, A. J. Nayana
We present the first deep X-ray observations of luminous fast blue optical transient (LFBOT) AT 2018cow at ∼3.7 yr since discovery, together with the reanalysis of the observation at δ t ∼ 220 days. X-ray emission is significantly detected at a location consistent with AT 2018cow. The very soft X-ray spectrum and sustained luminosity are distinct from the spectral and temporal behavior of the LFBOT