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arXiv 2020年

作者： Kotrlová, Andrea Šrámková, Eva Török, Gabriel Goluchová, Kateřina Jiří, Horák Straub, Odelle Lančová, Debora Stuchlík, Zdeňek Abramowicz, Marek A. Research Centre for Computational Physics and Data Processing Institute of Physics Silesian University in Opava Bezručovo nám. 13 OpavaCZ-746 01 Czech Republic Research Centre of Theoretical Physics and Astrophysics Institute of Physics Silesian University in Opava Bezručovo nám. 13 OpavaCZ-746 01 Czech Republic Astronomical Institute Academy of Sciences Boční II 1401 Praha 4-SpořilovCZ-14131 Czech Republic Max Planck Institute for Extraterrestrial Physics Gießenbachstraße 1 Garching85748 Germany LUTh Observatoire de Paris PSL Research University CNRS UMR 8109 Université Pierre et Marie Curie Université Paris Diderot 5 place Jules Janssen Meudon92195 France

We explore the influence of non-geodesic pressure forces that are present in an accretion disk on the frequencies of its axisymmetric and non-axisymmetric epicyclic oscillation modes. We discuss its implications for models of high-frequency quasi-periodic oscillations (QPOs) that have been observed in the X-ray flux of accreting black holes (BHs) in the three Galactic microquasars, GRS 1915+105, GRO J1655−40 and XTE J1550−564. We focus on previously considered QPO models that deal with low azimuthal number epicyclic modes, |m| ≤ 2, and outline the consequences for the estimations of BH spin, a ∈ [0, 1]. For four out of six examined models, we find only small, rather insignificant changes compared to the geodesic case. For the other two models, on the other hand, there is a fair increase of the estimated upper limit on the spin. Regarding the QPO model’s falsifiability, we find that one particular model from the examined set is incompatible with the data. If the microquasar’s spectral spin estimates that point to a > 0.65 were fully confirmed, two more QPO models would be ruled out. Moreover, if two very different values of the spin, such as a ≈ 0.65 in GRO J1655−40 vs. a ≈ 1 in GRS 1915+105, were confirmed, all the models except one would remain unsupported by our results. Finally, we discuss the implications for a model recently proposed in the context of neutron star (NS) QPOs as a disk-oscillation-based modification of the relativistic precession model. This model provides overall better fits of the NS data and predicts more realistic values of the NS mass compared to the relativistic precession model. We conclude that it also implies a significantly higher upper limit on the microquasar’s BH spin (a ∼ 0.75 vs. a ∼ 0.55). Copyright © 2020, The Authors. All rights reserved.

关键词： Stars

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21-cm Signal from the Epoch of Reionization: A Machine Learning upgrade to Foreground Removal with Gaussian Process Regression

arXiv

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arXiv 2023年

作者： Acharya, Anshuman Mertens, Florent Ciardi, Benedetta Ghara, Raghunath Koopmans, Léon V.E. Giri, Sambit K. Hothi, Ian Ma, Qing-Bo Mellema, Garrelt Munshi, Satyapan Max-Planck-Institut für Astrophysik Garching85748 Germany LERMA Observatoire de Paris PSL Research University CNRS Sorbonne Université ParisF-75014 France Astrophysics Research Centre Open University of Israel Ra'anana4353701 Israel Kapteyn Astronomical Institute University of Groningen P.O. Box 800 Groningen9700AV Netherlands Nordita KTH Royal Institute of Technology and Stockholm University Hannes Alfvéns väg 12 StockholmSE-106 91 Sweden Laboratoire de Physique de l'ENS ENS Université PSL CNRS Sorbonne Université Universitée Paris Cité Paris75005 France School of Physics and Electronic Science Guizhou Normal University Guiyang550001 China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University Guiyang550001 China The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova StockholmSE-10691 Sweden

In recent years, a Gaussian Process Regression (GPR) based framework has been developed for foreground mitigation from data collected by the LOw-Frequency ARray (LOFAR), to measure the 21-cm signal power spectrum from the Epoch of Reionization (EoR) and Cosmic Dawn. However, it has been noted that through this method there can be a significant amount of signal loss if the EoR signal covariance is misestimated. To obtain better covariance models,we propose to use a kernel trained on the GRIZZLY simulations using a Variational Auto-Encoder (VAE) based algorithm. In this work, we explore the abilities of this Machine Learning based kernel (VAE kernel) used with GPR, by testing it on mock signals from a variety of simulations, exploring noise levels corresponding to ≈10 nights (≈141 hours) and ≈100 nights (≈1410 hours) of observations with LOFAR. Our work suggests the possibility of successful extraction of the 21-cm signal within 2σ uncertainty in most cases using the VAE kernel, with better recovery of both shape and power than with previously used covariance models. We also explore the role of the excess noise component identified in past applications of GPR and additionally analyse the possibility of redshift dependence on the performance of the VAE kernel. The latter allows us to prepare for future LOFAR observations at a range of redshifts, as well as compare with results from other telescopes. © 2023, CC BY.

关键词： Cosmology

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UNCOVER spectroscopy confirms a surprising ubiquity of AGN in red galaxies at z > 5

arXiv

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arXiv 2023年

作者： Greene, Jenny E. Labbe, Ivo Goulding, Andy D. Furtak, Lukas J. Chemerynska, Iryna Kokorev, Vasily Dayal, Pratika Williams, Christina C. Wang, Bingjie Setton, David J. Burgasser, Adam J. Bezanson, Rachel Atek, Hakim Brammer, Gabriel Cutler, Sam E. Feldmann, Robert Fujimoto, Seiji Glazebrook, Karl de Graaff, Anna Khullar, Gourav Leja, Joel Marchesini, Danilo Maseda, Michael V. Matthee, Jorryt Miller, Tim B. Naidu, Rohan P. Nanayakkara, Themiya Oesch, Pascal A. Pan, Richard Papovich, Casey Price, Sedona H. van Dokkum, Pieter Weaver, John R. Whitaker, Katherine E. Zitrin, Adi Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia Department of Physics Ben-Gurion University of the Negev P.O. Box 653 Be'er-Sheva84105 Israel Institut d'Astrophysique de Paris CNRS Sorbonne Université 98bis Boulevard Arago Paris75014 France Kapteyn Astronomical Institute University of Groningen Groningen9700 AV Netherlands NSF's National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Avenue TucsonAZ85719 United States Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721 United States Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Department of Astronomy & Astrophysics UC San Diego La Jolla CA92093 United States Department of Physics and Astronomy PITT PACC University of Pittsburgh PittsburghPA15260 United States Niels Bohr Institute University of Copenhagen Jagtvej 128 København NDK-2200 Denmark Department of Astronomy University of Massachusetts AmherstMA01003 United States Institute for Computational Science University of Zurich ZurichCH-8057 Switzerland Department of Astronomy The University of Texas at Austin AustinTX78712 United States Centre for Astrophysics and Supercomputing Swinburne University of Technology PO Box 218 HawthornVIC3122 Australia Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany Department of Physics & Astronomy Tufts University MA02155 United States Department of Astronomy University of Wisconsin-Madison 475 N. Charter St. MadisonWI53706 United States Department of Physics ETH Zuric

JWST is revealing a new population of dust-reddened broad-line active galactic nuclei (AGN) at redshifts z 5. Here we present deep NIRSpec/Prism spectroscopy from the Cycle 1 Treasury program UNCOVER of 17 AGN candidates selected to be compact, with red continua in the rest-frame optical but with blue slopes in the UV. From NIRCam photometry alone, they could have been dominated by dusty star formation or AGN. Here we show that the majority of the compact red sources in UNCOVER are dust-reddened AGN: 60% show definitive evidence for broad-line Hα with FWHM> 2000 km/s, for 20% current data are inconclusive, and 20% are brown dwarf stars. We propose an updated photometric criterion to select red z > 5 AGN that excludes brown dwarfs and is expected to yield > 80% AGN. Remarkably, among all zphot > 5 galaxies with F277W−F444W> 1 in UNCOVER at least 33% are AGN regardless of compactness, climbing to at least 80% AGN for sources with F277W−F444W> 1.6. The confirmed AGN have black hole masses of 107 − 109 M☉. While their UV-luminosities (−16 > MUV > −20 AB mag) are low compared to UV-selected AGN at these epochs, consistent with percent-level scattered AGN light or low levels of unobscured star formation, the inferred bolometric luminosities are typical of 107 − 109 M☉ black holes radiating at ∼ 10 − 40% of Eddington. The number densities are surprisingly high at ∼ 10−5 Mpc−3 mag−1, 100 times more common than the faintest UV-selected quasars, while accounting for ∼ 1% of the UV-selected galaxies. While their UV-faintness suggest they may not contribute strongly to reionization, their ubiquity poses challenges to models of black hole growth. © 2023, CC BY.

关键词： Active Galactic Nuclei

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Collapsars as Sites of r-process Nucleosynthesis: Systematic Near-Infrared Follow-up of Type Ic-BL Supernovae

arXiv

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arXiv 2023年

作者： Anand, Shreya Barnes, Jennifer Yang, Sheng Kasliwal, Mansi M. Coughlin, Michael W. Sollerman, Jesper De, Kishalay Fremling, Christoffer Corsi, Alessandra Ho, Anna Y.Q. Balasubramanian, Arvind Omand, Conor Srinivasaragavan, Gokul P. Cenko, S. Bradley Ahumada, Tomás Andreoni, Igor Dahiwale, Aishwarya Das, Kaustav Kashyap Jencson, Jacob Karambelkar, Viraj Kumar, Harsh Metzger, Brian D. Perley, Daniel Sarin, Nikhil Schweyer, Tassilo Schulze, Steve Sharma, Yashvi Sit, Tawny Stein, Robert Tartaglia, Leonardo Tinyanont, Samaporn Tzanidakis, Anastasios van Roestel, Jan Yao, Yuhan Bloom, Joshua S. Cook, David O. Dekany, Richard Graham, Matthew J. Groom, Steven L. Kaplan, David L. Masci, Frank J. Medford, Michael S. Riddle, Reed Zhang, Chaoran Cahill Center for Astrophysics California Institute of Technology PasadenaCA91125 United States Kavli Institute for Theoretical Physics Kohn Hall University of California Santa BarbaraCA93106 United States The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova StockholmSE-10691 Sweden Henan Academy of Sciences Henan Zhengzhou450046 China School of Physics and Astronomy University of Minnesota MinneapolisMN55455 United States MIT-Kavli Institute for Astrophysics and Space Research 77 Massachusetts Ave. CambridgeMA02139 United States Department of Physics and Astronomy Texas Tech University Box 1051 LubbockTX79409-1051 United States Department of Astronomy Cornell University IthacaNY14850 United States Department of Astronomy and Astrophysics Tata Institute of Fundamental Research Mumbai400005 India Department of Astronomy University of Maryland College ParkMD20742 United States Astrophysics Science Division NASA Goddard Space Flight Center MC 661 GreenbeltMD20771 United States Joint Space-Science Institute University of Maryland College ParkMD20742 United States Department of Physics and Astronomy The Johns Hopkins University BaltimoreMD21218 United States Center for Astrophysics Harvard University 60 Garden St. CambridgeMA02158 United States LSSTC Data Science Fellow 2018 Department of Physics Columbia Astrophysics Laboratory Columbia University Pupin Hall New YorkNY10027 United States Center for Computational Astrophysics Flatiron Institute 162 5th Ave New YorkNY10010 United States Astrophysics Research Institute Liverpool John Moores University IC2 Liverpool Science Park 146 Brownlow Hill LiverpoolL3 5RF United Kingdom Nordita Stockholm University KTH Royal Institute of Technology Hannes Alfvéns väg 12 StockholmSE-106 91 Sweden The Oskar Klein Centre Department of Physics Stockholm University AlbaNova StockholmSE-106 91 Sweden Center for Interdisciplinary Exploration and Research in Ast

One of the open questions following the discovery of GW170817 is whether neutron star mergers are the only astrophysical sites capable of producing r-process elements. Simulations have shown that 0.01-0.1M☉ of r-process material could be generated in the outflows originating from the accretion disk surrounding the rapidly rotating black hole that forms as a remnant to both neutron star mergers and collapsing massive stars associated with long-duration gamma-ray bursts (collapsars). The hallmark signature of r-process nucleosynthesis in the binary neutron star merger GW170817 was its long-lasting near-infrared emission, thus motivating a systematic photometric study of the light curves of broadlined stripped-envelope (Ic-BL) supernovae (SNe) associated with collapsars. We present the first systematic study of 25 SNe Ic-BL—including 18 observed with the Zwicky Transient Facility and 7 from the literature—in the optical/near-infrared bands to determine what quantity of r-process material, if any, is synthesized in these explosions. Using semi-analytic models designed to account for r-process production in SNe Ic-BL, we perform light curve fitting to derive constraints on the r-process mass for these SNe. We also perform independent light curve fits to models without r-process. We find that the r-process-free models are a better fit to the light curves of the objects in our sample. Thus we find no compelling evidence of r-process enrichment in any of our objects. Further high-cadence infrared photometric studies and nebular spectroscopic analysis would be sensitive to smaller quantities of r-process ejecta mass or indicate whether all collapsars are completely devoid of r-process nucleosynthesis. © 2023, CC BY.

关键词： Timing circuits

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SN 2023ixf in Messier 101: Photo-ionization of Dense, Close-in Circumstellar Material in a Nearby Type II Supernova

arXiv

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arXiv 2023年

作者： Jacobson-Galán, W.V. Dessart, L. Margutti, R. Chornock, R. Foley, R.J. Kilpatrick, C.D. Jones, D.O. Taggart, K. Angus, C.R. Bhattacharjee, S. Braff, L.A. Brethauer, D. Burgasser, A.J. Cao, F. Carlile, C.M. Chambers, K.C. Coulter, D.A. Dominguez-Ruiz, E. Dickinson, C.B. de Boer, T. Gagliano, A. Gall, C. Gao, H. Gates, E.L. Gomez, S. Guolo, M. Halford, M.R.J. Hjorth, J. Huber, M.E. Johnson, M.N. Karpoor, P.R. Laskar, T. LeBaron, N. Li, Z. Lin, Y. Loch, S.D. Lynam, P.D. Magnier, E.A. Maloney, P. Matthews, D.J. McDonald, M. Miao, H.-Y. Milisavljevic, D. Pan, Y.-C. Pradyumna, S. Ransome, C.L. Rees, J.M. Rest, A. Rojas-Bravo, C. Sandford, N.R. Ascencio, L. Sandoval Sanjaripour, S. Savino, A. Sears, H. Sharei, N. Smartt, S.J. Softich, E.R. Theissen, C.A. Tinyanont, S. Tohfa, H. Villar, V.A. Wang, Q. Wainscoat, R.J. Westerling, A.L. Wiston, E. Wozniak, M.A. Yadavalli, S.K. Zenati, Y. Department of Astronomy University of California BerkeleyCA94720 United States Institut d'Astrophysique de Paris CNRS-Sorbonne Université 98 bis boulevard Arago ParisF-75014 France Department of Physics University of California BerkeleyCA94720 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Gemini Observatory NSF's NOIRLab 670 N. A'ohoku Place HiloHI96720 United States DARK Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen2200 Denmark Graduate Institute of Astronomy National Central University 300 Zhongda Road Zhongli Taoyuan32001 Taiwan Department of Astronomy & Astrophysics UC San Diego La Jolla CA92093 United States Department of Statistics University of California RiversideCA92521 United States Center for Astrophysics and Space Sciences University of California La Jolla San DiegoCA92093 United States Institute for Astronomy University of Hawaii 2680 Woodlawn Drive HonoluluHI96822 United States Department of Astronomy University of Illinois at Urbana-Champaign 1002 W. Green St. IL61801 United States Center for Astrophysical Surveys National Center for Supercomputing Applications UrbanaIL61801 United States University of California Observatories/Lick Observatory Mount HamiltonCA95140 United States Space Telescope Science Institute BaltimoreMD21218 United States Department of Physics and Astronomy The Johns Hopkins University BaltimoreMD21218 United States Department of Physics Auburn University 380 Duncan Drive AuburnAL36849 United States Department of Physics University of California Santa CruzCA95064 United States Department of Physics & Astronomy University of Utah Salt Lake CityUT84112 United States Department of Earth and Planetary Sciences University of California RiversideCA92521 United States Department of Physics & Astronom

We present UV/optical observations and models of supernova (SN) 2023ixf, a type II SN located in Messier 101 at 6.9 Mpc. Early-time ("flash") spectroscopy of SN 2023ixf, obtained primarily at Lick Observatory, reveals emission lines of H i, He i/ii, C iv, and N iii/iv/v with a narrow core and broad, symmetric wings arising from the photo-ionization of dense, close-in circumstellar material (CSM) located around the progenitor star prior to shock breakout. These electron-scattering broadened line profiles persist for ∼8 days with respect to first light, at which time Doppler broadened features from the fastest SN ejecta form, suggesting a reduction in CSM density at r 1015 cm. The early-time light curve of SN 2023ixf shows peak absolute magnitudes (e.g., Mu = −18.6 mag, Mg = −18.4 mag) that are 2 mag brighter than typical type II supernovae, this photometric boost also being consistent with the shock power supplied from CSM interaction. Comparison of SN 2023ixf to a grid of light curve and multi-epoch spectral models from the non-LTE radiative transfer code CMFGEN and the radiation-hydrodynamics code HERACLES suggests dense, solar-metallicity, CSM confined to r = (0.5 − 1) × 1015 cm and a progenitor mass-loss rate of M¤ = 10−2 M☉ yr−1. For the assumed progenitor wind velocity of vw = 50 km s−1, this corresponds to enhanced mass-loss (i.e., "super-wind" phase) during the last ∼3-6 years before explosion. © 2023, CC0.

关键词： Supernovae

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The Cosmic Evolution Early Release Science Survey (CEERS)

arXiv

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arXiv 2025年

作者： Finkelstein, Steven L. Bagley, Micaela B. Haro, Pablo Arrabal Dickinson, Mark Ferguson, Henry C. Kartaltepe, Jeyhan S. Kocevski, Dale D. Koekemoer, Anton M. Lotz, Jennifer M. Papovich, Casey Pérez-González, Pablo G. Pirzkal, Nor Somerville, Rachel S. Trump, Jonathan R. Yang, Guang Yung, L.Y. Aaron Fontana, Adriano Grazian, Andrea Grogin, Norman A. Kewley, Lisa J. Kirkpatrick, Allison Larson, Rebecca L. Pentericci, Laura Ravindranath, Swara Wilkins, Stephen M. Almaini, Omar Amorín, Ricardo O. Barro, Guillermo Bhatawdekar, Rachana Bisigello, Laura Brooks, Madisyn Buitrago, Fernando Calabrò, Antonello Castellano, Marco Cheng, Yingjie Cleri, Nikko J. Cole, Justin W. Cooper, M.C. Cooper, Olivia R. Costantin, Luca Cox, Isa G. Croton, Darren Daddi, Emanuele Davis, Kelcey Dekel, Avishai Elbaz, David Fernández, Vital Fujimoto, Seiji Gandolfi, Giovanni Gardner, Jonathan P. Gawiser, Eric Giavalisco, Mauro Gómez-Guijarro, Carlos Guo, Yuchen Gupta, Ansh R. Hathi, Nimish P. Harish, Santosh Henry, Aurélien Hirschmann, Michaela Hu, Weida Hutchison, Taylor A. Iyer, Kartheik G. Jaskot, Anne E. Jha, Saurabh W. Jung, Intae Kokorev, Vasily Kurczynski, Peter Leung, Gene C.K. Llerena, Mario Long, Arianna S. Lucas, Ray A. Lu, Shiying McGrath, Elizabeth J. McIntosh, Daniel H. Merlin, Emiliano Morales, Alexa M. Napolitano, Lorenzo Pacucci, Fabio Pandya, Viraj Rafelski, Marc Rodighiero, Giulia Rose, Caitlin Santini, Paola Seillé, Lise-Marie Simons, Raymond C. Shen, Lu Straughn, Amber N. Tacchella, Sandro Vanderhoof, Brittany N. Vega-Ferrero, Jesús Weiner, Benjamin J. Willmer, Christopher N.A. Zhu, Peixin Bell, Eric F. Wuyts, Stijn Holwerda, Benne W. Wang, Xin Wang, Weichen Zavala, Jorge A. Department of Astronomy The University of Texas at Austin AustinTX United States Astrophysics Science Division NASA Goddard Space Flight Center 8800 Greenbelt Rd GreenbeltMD20771 United States NSF’s National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Ave. TucsonAZ85719 United States Space Telescope Science Institute BaltimoreMD United States Laboratory for Multiwavelength Astrophysics School of Physics and Astronomy Rochester Institute of Technology 84 Lomb Memorial Drive RochesterNY14623 United States Department of Physics and Astronomy Colby College WatervilleME04901 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Gemini Observatory NSF’s National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Ave. TucsonAZ85719 United States George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy Department of Physics and Astronomy Texas A&M University College StationTX United States Ctra. de Ajalvir km 4 Torrejón de Ardoz MadridE-28850 Spain ESA/AURA Space Telescope Science Institute Center for Computational Astrophysics Flatiron Institute 162 5th Avenue New YorkNY10010 United States Department of Physics University of Connecticut 196A Auditorium Road Unit 3046 StorrsCT06269 United States Nanjing Institute of Astronomical Optics and Technology Nanjing210042 China INAF - Osservatorio Astronomico di Roma via di Frascati 33 Monte Porzio Catone00078 Italy INAF–Osservatorio Astronomico di Padova Vicolo dell’Osservatorio 5 PadovaI-35122 Italy Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States Department of Physics and Astronomy University of Kansas LawrenceKS66045 United States Astronomy Centre University of Sussex Falmer BrightonBN1 9QH United Kingdom Institute of Space Sciences and Astronomy University of Malta MsidaMSD 2080 Malta School of Physics and Astronomy University of Notting

We present the Cosmic Evolution Early Release Science (CEERS) Survey, a 77.2 hour Director’s Discretionary Early Release Science Program. CEERS demonstrates, tests, and validates efficient extragalactic surveys using coordinated, overlapping parallel observations with the JWST instrument suite, including NIRCam and MIRI imaging, NIRSpec low (R∼100) and medium (R∼1000) resolution spectroscopy, and NIRCam slitless grism (R∼1500) spectroscopy. CEERS targets the Hubble Space Telescope-observed region of the Extended Groth Strip (EGS) field, supported by a rich set of multiwavelength data. CEERS facilitated immediate community science in both of the extragalactic core JWST science drivers "First Light" and "Galaxy Assembly," including: 1) The discovery and characterization of large samples of galaxies at z 10 from ∼90 arcmin2 of NIRCam imaging, constraining their abundance and physical nature;2) Deep spectra of >1000 galaxies, including dozens of galaxies at 6 3;and 4) Characterizing galaxy mid-IR emission with MIRI to study dust-obscured star-formation and supermassive black hole growth at z ∼ 1–3. As a legacy product for the community, the CEERS team has provided several data releases, accompanied by detailed notes on the data reduction procedures and notebooks to aid in reproducibility. In addition to an overview of the survey and quality of the data, we provide science highlights from the first two years with CEERS data. Copyright © 2025, The Authors. All rights reserved.

关键词： Cosmology

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The Wide-field Spectroscopic Telescope (WST) Science White Paper

arXiv

引用

arXiv 2024年

作者： Mainieri, Vincenzo Anderson, Richard I. Brinchmann, Jarle Cimatti, Andrea Ellis, Richard Hill, Vanessa Kneib, Jean-Paul McLeod, Anna Opitom, Cyrielle Roth, Martin M. Sáez, Paula Sánchez Smiljanic, Rodolfo Tolstoy, Eline Bacon, Roland Randich, Sofia Pasquini, Luca Barsanti, Stefania Bryant, Julia Bryson, Ian Casali, Mark Colless, Matthew Couch, Warrick Danielski, Camilla Dierickx, Philippe Driver, Simon Fontana, Adriano Garilli, Bianca de Jong, Roelof S. Lee, David Lehnert, Matt Magrini, Laura Montet, Ben Sanchez-Janssen, Ruben Pandey-Pommier, Mamta Sargent, Mark Schipani, Pietro Steinmetz, Matthias Travouillon, Tony Tresse, Laurence Vernet, Joël Yeche, Christophe Ziegler, Bodo Audard, Marc Arévalo, Patricia Bayo Aran, Amelia M. Bisero, Sofia Bisogni, Susanna Blondin, Stéphane Bonito, Rosaria Branchesi, Marica Catelan, Márcio D'Ammando, Filippo Dainotti, Maria G. De Cia, Annalisa Dhawan, Suhail Dupletsa, Ulyana Hazra, Nandini Ilić, Dragana Ivanov, Valentin D. Izzo, Luca Kovačević, Andjelka B. Kuncarayakti, Hanindyo Kwon, Yuna La Forgia, Fiorangela Lazzarin, Monica Lira, Paulina Loffredo, Eleonora Maguire, Kate Majidi, Fatemeh Z. Marconi, Marcella McGee, Sean Migliorini, Alessandra Minniti, Dante Nicholl, Matt Onori, Francesca Pala, Anna F. Panda, Swayamtrupta Pawlak, Michal Pessi, Priscila J. Popović, Luka Č. Smith, Graham P. Vergani, Susanna D. Vietri, Giustina Ye, Quanzhi Zafar, Tayyaba Matsuno, Tadafumi Kordopatis, Georges Annibali, Francesca Bayo, Amelia Bellazzini, Michele Beltran, Maria Teresa Berni, Leda Bianchi, Simone Biazzo, Katia Bland-Hawthorn, Joss Boffin, Henri M.J. Bono, Giuseppe Bowman, Dominic Braga, Vittorio F. Bragaglia, Angela Brucalassi, Anna Busà, Innocenza Casali, Giada Casasola, Viviana Castro, Norberto Cavallo, Lorenzo Chiappini, Cristina Colzi, Laura Damiani, Francesco da Silva, Ronaldo D'Orazi, Valentina Escorza, Ana Fabrizio, Michele Fiorentino, Giuliana Fontani, Francesco François, Patrick Galindo-Guil, Francisco J. Galli, Daniele Garcia-Rojas, Jorge Guarcello, Mario Giuseppe Helmi, Am European Southern Observatory Karl-Schwarzschild-Strasse 2 Garching bei München85748 Germany Switzerland Instituto de Astrofísica e Ciências do Espaço Universidade do Porto Portugal Dipartimento di Fisica e Astronomia "Augusto Righi" Alma Mater Studiorum Università di Bologna Italy Department of Physics and Astronomy University College London United Kingdom Observatoire de la Côte d'Azur Université Côte d'Azur CNRS Laboratoire Lagrange France Centre for Extragalactic Astronomy Department of Physics Durham University United Kingdom Institute for Computational Cosmology Department of Physics University of Durham United Kingdom Institute for Astronomy University of Edinburgh United Kingdom Germany Nicolaus Copernicus Astronomical Center Polish Academy of Sciences Poland Kapteyn Astronomical Institute University of Groningen Netherlands France INAF - Osservatorio Astrofisico di Arcetri Italy Stockholm University Sweden INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna Italy Universidad de Valparaíso Chile University of Geneva Switzerland Research School of Astronomy and Astrophysics Australian National University CanberraACT2611 Australia Australia Instituto de Astrofísica de Canarias Spain Universidad de La Laguna Spain SISSA - Scuola Internazionale Superiore di Studi Avanzati Italy University of Florence Italy INAF - Osservatorio Astronomico di Roma Italy GEPI Observatoire de Paris Universite PSL CNRS France INAF Istituto di Astrofisica Spaziale e Fisica cosmica Milano Italy Sydney Institute for Astronomy School of Physics The University of Sydney Australia Aix Marseille Univ CNRS CNES LAM France INAF - Osservatorio Astronomico di Palermo Italy University of Rome Tor Vergata Italy Newcastle University United Kingdom Italy UK Astronomy Technology Ctr. Royal Observatory Edinburgh United Kingdom INAF OACT Italy Dipartimento di Fisica Università degli Studi di Torino Italy Istituto Nazionale di Fisica Nucleare INFN Sezione di

The WST is proposed as a new facility dedicated to the efficient delivery of spectroscopic surveys and this white paper summarises the initial concept as well as the corresponding science cases. It will provide an end-to-end service from the preparation of surveys to the delivery of high-quality calibrated science data product. Uniquely, it will have the ability to simultaneously deliver fibre-fed multi-object spectroscopy over a large field of view (MOS) and integral field imaging spectroscopy of a central field of 3 × 3 arcmin2 (IFS). WST will fill a crucial gap in the astronomical landscape and will allow full exploitation of major current and upcoming ground and space-based facilities. WST will address outstanding scientific questions in the areas of cosmology;galaxy assembly, evolution, and enrichment, including our own Milky Way;origin of stars and planets;time domain and multi-messenger astrophysics. WST features a 12 meter aperture telescope that covers the UV to the H band and operates in seeing limited conditions. Its field of view (FoV) of 3.1 deg2 will be the largest of any telescope equipped with a MOS. In particular, its FoV is 2.5 times larger than PFS@Subaru and a remarkable 22 times larger than MOONS@VLT. In addition, the WST has a substantial aperture, twice as large (100 square metres) as its 8 meter class competitors. A central circular area with a diameter of 13 arcmin is available for simultaneous IFS observations. Within this area, the IFS with a FoV of 3 × 3 arcmin2 (9 times larger than MUSE@VLT) can be utilised simultaneously with the MOS. In addition, the IFS can be used to mosaic a larger area within the 13 arcmin circle (an area larger than the entire FoV of the ELT) while the MOS positioner can perform multiple configurations. The WST operational model will also implement target of opportunity (ToO) operations at both the telescope and MOS fibre levels to support the time domain science cases. The demand for a facility dedicated to spect

关键词： Telescopes

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Inhomogeneous terminators on the exoplanet WASP-39 b

arXiv

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arXiv 2024年

作者： Espinoza, Néstor Steinrueck, Maria E. Kirk, James MacDonald, Ryan J. Savel, Arjun B. Arnold, Kenneth Kempton, Eliza M.-R. Murphy, Matthew M. Carone, Ludmila Zamyatina, Maria Lewis, David A. Samra, Dominic Kiefer, Sven Rauscher, Emily Christie, Duncan Mayne, Nathan Helling, Christiane Rustamkulov, Zafar Parmentier, Vivien May, Erin M. Carter, Aarynn L. Zhang, Xi López-Morales, Mercedes Allen, Natalie Blecic, Jasmina Decin, Leen Mancini, Luigi Molaverdikhani, Karan Rackham, Benjamin V. Palle, Enric Tsai, Shang-Min Ahrer, Eva-Maria Bean, Jacob L. Crossfield, Ian J.M. Haegele, David Hébrard, Eric Kreidberg, Laura Powell, Diana Schneider, Aaron D. Welbanks, Luis Wheatley, Peter Brahm, Rafael Crouzet, Nicolas Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Department of Physics & Astronomy Johns Hopkins University BaltimoreMD21218 United States Königstuhl 17 HeidelbergD-69117 Germany Department of Astronomy & Astrophysics University of Chicago ChicagoIL United States Department of Physics Imperial College London Prince Consort Road LondonSW7 2AZ United Kingdom Department of Astronomy University of Michigan 1085 S. University Ave. Ann ArborMI48109 United States Department of Astronomy University of Maryland College ParkMD20742 United States Department of Astronomy Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721 United States Space Research Institute Austrian Academy of Sciences Schmiedlstrasse 6 GrazA-8042 Austria Department of Physics and Astronomy Faculty of Environment Science and Economy University of Exeter ExeterEX4 4QL United Kingdom Institute for Theoretical Physics and Computational Physics Graz University of Technology Petersgasse 16 Graz Austria Institute of Astronomy KU Leuven Celestijnenlaan 200D Leuven3001 Belgium Centre for Exoplanet Science University of St Andrews North Haugh St AndrewsKY169SS United Kingdom Fakultät für Mathematik Physik und Geodäsie TU Graz Petersgasse 16 GrazA-8010 Austria Observatoire de la Côte d'Azur Université Côte d'Azur CNRS Laboratoire Lagrange Nice France Johns Hopkins APL 11100 Johns Hopkins Rd LaurelMD20723 United States Department of Astronomy & Astrophysics University of California Santa Cruz 1156 High St Santa CruzCA95064 United States Department of Earth and Planetary Sciences University of California Santa Cruz 1156 High St Santa CruzCA95064 United States Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Department of Physics New York University Abu Dhabi PO Box 129188 Abu Dhabi United Arab Emirates New York University Abu Dhabi PO Box 129188 Abu

Transmission spectroscopy has been a workhorse technique over the past two decades to constrain the physical and chemical properties of exoplanet atmospheres 1-5. One of its classical key assumptions is that the portion of the atmosphere it probes - the terminator region - is homogeneous. Several works in the past decade, however, have put this into question for highly irradiated, hot (Teq 1000 K) gas giant exoplanets both empirically 6-10 and via 3-dimensional modelling 11-17. While models predict clear differences between the evening (day-to-night) and morning (night-to-day) terminators, direct morning/evening transmission spectra in a wide wavelength range has not been reported for an exoplanet to date. Under the assumption of precise and accurate orbital parameters on WASP-39 b, here we report the detection of inhomogeneous terminators on the exoplanet WASP-39 b, which allows us to retrieve its morning and evening transmission spectra in the near-infrared (2 − 5 µm) using JWST. We observe larger transit depths in the evening which are, on average, 405±88 ppm larger than the morning ones, also having qualitatively larger features than the morning spectrum. The spectra are best explained by models in which the evening terminator is hotter than the morning terminator by 177+65−57 K with both terminators having C/O ratios consistent with solar. General circulation models (GCMs) predict temperature differences broadly consistent with the above value and point towards a cloudy morning terminator and a clearer evening terminator. Copyright © 2024, The Authors. All rights reserved.

关键词： Infrared devices

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Fundamental physics Opportunities with the Next-Generation Event Horizon Telescope

arXiv

引用

arXiv 2023年

作者： Ayzenberg, Dimitry Blackburn, Lindy Brito, Richard Britzen, Silke Broderick, Avery E. Carballo-Rubio, Raúl Cardoso, Vitor Chael, Andrew Chatterjee, Koushik Chen, Yifan Cunha, Pedro V.P. Davoudiasl, Hooman Denton, Peter B. Doeleman, Sheperd S. Eichhorn, Astrid Eubanks, Marshall Fang, Yun Foschi, Arianna Fromm, Christian M. Galison, Peter Ghosh, Sushant G. Gold, Roman Gurvits, Leonid I. Hadar, Shahar Held, Aaron Houston, Janice Hu, Yichao Johnson, Michael D. Kocherlakota, Prashant Natarajan, Priyamvada Olivares, Héctor Palumbo, Daniel Pesce, Dominic W. Rajendran, Surjeet Roy, Rittick Saurabh Shao, Lijing Tahura, Shammi Tamar, Aditya Tiede, Paul Vincent, Frédéric H. Visinelli, Luca Wang, Zhiren Wielgus, Maciek Xue, Xiao Yakut, Kadri Yang, Huan Younsi, Ziri Theoretical Astrophysics Eberhard-Karls Universität Tübingen TübingenD-72076 Germany Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Harvard University 20 Garden Street CambridgeMA02138 United States CENTRA Departamento de Física Instituto Superior Técnico – IST Universidade de Lisboa – UL Avenida Rovisco Pais 1 Lisboa1049-001 Portugal Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 BonnD-53121 Germany Perimeter Institute for Theoretical Physics 31 Caroline Street North WaterlooONN2L 2Y5 Canada Department of Physics and Astronomy University of Waterloo 200 University Avenue West WaterlooONN2L 3G1 Canada Waterloo Centre for Astrophysics University of Waterloo WaterlooONN2L 3G1 Canada CP3-Origins University of Southern Denmark Campusvej 55 Odense MDK-5230 Denmark Florida Space Institute University of Central Florida 12354 Research Parkway Partnership 1 OrlandoFL32826 United States Niels Bohr International Academy Niels Bohr Institute Blegdamsvej 17 Copenhagen2100 Denmark Princeton Gravity Initiative Jadwin Hall Princeton University PrincetonNJ08544 United States Department of Physics University of Maryland College ParkMD20742 United States Institute for Research in Electronics and Applied Physics University of Maryland College ParkMD20742 United States Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States Campus de Santiago Aveiro3810-183 Portugal High Energy Theory Group Physics Department Brookhaven National Laboratory UptonNY11973 United States Asteroid Initiatives LLC United States Perimeter Institute for Theoretical Physics WaterlooONN2L2Y5 Canada Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China Institut für Theoretische Physik und Astrophysik Universität Würzburg Emil-Fischer-Strasse 31 Würzburg97074 Germany Institut für Theoretische Physik Goethe Universität Frankfurt Max-von

The Event Horizon Telescope (EHT) Collaboration recently published the first images of the supermassive black holes in the cores of the Messier 87 and Milky Way galaxies. These observations have provided a new means to study supermassive black holes and probe physical processes occurring in the strong-field regime. We review the prospects of future observations and theoretical studies of supermassive black hole systems with the next-generation Event Horizon Telescope (ngEHT), which will greatly enhance the capabilities of the existing EHT array. These enhancements will open up several previously inaccessible avenues of investigation, thereby providing important new insights into the properties of supermassive black holes and their environments. This review describes the current state of knowledge for five key science cases, summarising the unique challenges and opportunities for fundamental physics investigations that the ngEHT will enable. Copyright © 2023, The Authors. All rights reserved.

关键词： Telescopes

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Two Distinct Classes of Quiescent Galaxies at Cosmic Noon Revealed by JWST PRIMER and UNCOVER

arXiv

引用

arXiv 2023年

作者： Cutler, Sam E. Whitaker, Katherine E. Weaver, John R. Wang, Bingjie Pan, Richard Bezanson, Rachel Furtak, Lukas J. Labbe, Ivo Leja, Joel Price, Sedona H. Cheng, Yingjie Clausen, Maike Cullen, Fergus Dayal, Pratika Graaff, Anna D.E. Dickinson, Mark Dunlop, James S. Feldmann, Robert Franx, Marijn Giavalisco, Mauro Glazebrook, Karl Greene, Jenny E. Grogin, Norman A. Illingworth, Garth Koekemoer, Anton M. Kokorev, Vasily Marchesini, Danilo Maseda, Michael V. Miller, Tim B. Nanayakkara, Themiya Nelson, Erica J. Setton, David J. Shipley, Heath Suess, Katherine A. Department of Astronomy University of Massachusetts AmherstMA01003 United States Denmark Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Department of Physics & Astronomy Tufts University MA02155 United States Department of Physics and Astronomy PITT PACC University of Pittsburgh PittsburghPA15260 United States Physics Department Ben-Gurion University of the Negev P.O. Box 653 Be’er-Sheva84105 Israel Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia Max Planck Institute of Astronomy Königstuhl 17 Heidelberg69117 Germany Institute for Astronomy University of Edinburgh Royal Observatory EdinburghEH9 3HJ United Kingdom Kapteyn Astronomical Institute University of Groningen P.O. Box 800 Groningen9700 AV Netherlands Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany NSF’s National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Ave. TucsonAZ85719 United States Institute for Computational Science University of Zurich ZurichCH-8057 Switzerland Leiden Observatory Leiden University P.O. Box 9513 Leiden2300 RA Netherlands Centre for Astrophysics and Supercomputing Swinburne University of Technology PO Box 218 HawthornVIC3122 Australia Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States Space Telescope Science Institute BaltimoreMD21218 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Department of Astronomy University of Wisconsin-Madison 475 N. Charter St. MadisonWI53706 United States Northwestern University 1800 Sherman Ave EvanstonIL

关键词： Galaxies

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