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arXiv 2021年

作者： Fong, Wen-Fai Dong, Yuxin Leja, Joel Bhandari, Shivani Day, Cherie K. Deller, Adam T. Kumar, Pravir Prochaska, J. Xavier Scott, Danica R. Bannister, Keith W. Eftekhari, Tarraneh Gordon, Alexa C. Heintz, Kasper E. James, Clancy W. Kilpatrick, Charles D. Mahony, Elizabeth K. Escorial, Alicia Rouco Ryder, Stuart D. Shannon, Ryan M. Tejos, Nicolas Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Purdue University Department of Physics and Astronomy 525 Northwestern Avenue West LafayetteIN47907 United States Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States CSIRO Space and Astronomy PO Box 76 EppingNSW1710 Australia Centre for Astrophysics and Supercomputing Swinburne University of Technology HawthornVIC3122 Australia Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States 5-1-5 Kashiwanoha Kashiwa277-8583 Japan International Centre for Radio Astronomy Research Curtin University BentleyWA6102 Australia Center for Astrophysics | Harvard & Smithsonian 60 Garden St. CambridgeMA02138 United States Centre for Astrophysics and Cosmology Science Institute University of Iceland Dunhagi 5 Reykjavík107 Iceland Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen Ø2100 Denmark Department of Physics & Astronomy Macquarie University NSW2109 Australia Macquarie University Research Centre for Astronomy Astrophysics & Astrophotonics SydneyNSW2109 Australia Instituto de Física Pontificia Universidad Católica de Valparaíso Casilla Valparaíso 4059 Chile

We present the Australian Square Kilometre Array Pathfinder (ASKAP) localization and follow-up observations of the host galaxy of the repeating fast radio burst (FRB) source, FRB 20201124A, the fifth such extragalactic repeating FRB with an identified host. From spectroscopic observations using the 6.5-m MMT Observatory, we derive a redshift of z = 0.0979 ±0.0001, a star formation rate inferred from Hα emission of SFR(Hα) ≈ 2.1 M☉ yr-1, and a gas-phase metallicity of 12+log(O/H)≈ 9.0. By jointly modeling the 12-filter optical-mid-infrared (MIR) photometry and spectroscopy of the host, we infer a median stellar mass of ≈ 2 × 1010 M☉, internal dust extinction of AV ≈ 1 - 1.5 mag, and a mass-weighted stellar population age of ≈ 5 - 6 Gyr. Connecting these data to the radio and X-ray observations, we cannot reconcile the broad-band behavior with strong AGN activity and instead attribute the dominant source of persistent radio emission to star formation, likely originating from the circumnuclear region of the host. The modeling also indicates a hot dust component contributing to the MIR luminosity at a level of ≈ 10 - 30%. We model the host galaxy's star formation and mass assembly histories, finding that the host assembled > 90% of its mass by 1 Gyr ago and exhibited a fairly constant SFR for most of its existence, with no clear evidence of past star-burst activity. Copyright © 2021, The Authors. All rights reserved.

关键词： Stars

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AN X-RAY CENSUS OF FAST RADIO BURST HOST GALAXIES: CONSTRAINTS ON AGN AND X-RAY COUNTERPARTS

arXiv

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arXiv 2023年

作者： Eftekhari, T. Fong, W. Gordon, A.C. Sridhar, N. Kilpatrick, C.D. Bhandari, S. Deller, A.T. Dong, Y. Escorial, A. Rouco Heintz, K.E. Leja, J. Margalit, B. Metzger, B.D. Pearlman, A.B. Prochaska, J.X. Ryder, S.D. Scholz, P. Shannon, R.M. Tejos, N. Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Department of Astronomy Columbia University New YorkNY10027 United States Group Columbia University New YorkNY10027 United States ASTRON Netherlands Institute for Radio Astronomy Oude Hoogeveensedijk 4 Dwingeloo7991 PD Netherlands Joint institute for VLBI ERIC Oude Hoogeveensedijk 4 Dwingeloo7991 PD Netherlands Anton Pannekoek Institute for Astronomy University of Amsterdam Science Park 904 Amsterdam1098 XH Netherlands CSIRO Space and Astronomy PO Box 76 EppingNSW1710 Australia Centre for Astrophysics and Supercomputing Swinburne University of Technology John St HawthornVIC3122 Australia Camino Bajo del Castillo s/n Villanueva de la Caada Madrid28692 Spain Denmark Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen NDK-2200 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 Astronomy Department and Theoretical Astrophysics Center University of California Berkeley BerkeleyCA94720 United States Center for Computational Astrophysics Flatiron Institute 162 5th Ave New YorkNY10010 United States Department of Physics McGill University 3600 rue University MontréalQCH3A 2T8 Canada Trottier Space Institute McGill University 3550 rue University MontréalQCH3A 2A7 Canada Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States 5-1-5 Kashiwanoha Kashiwa277-8583 Japan Division of Science National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan School of Mathematical and Physical Sciences Macquarie University NSW2109 Australia Astrophysics and Space Techno

We present the first X-ray census of fast radio burst (FRB) host galaxies to conduct the deepest search for AGN and X-ray counterparts to date. Our sample includes seven well-localized FRBs with unambiguous host associations and existing deep Chandra observations, including two events for which we present new observations. We find evidence for AGN in two FRB host galaxies based on the presence of X-ray emission coincident with their centers, including the detection of a luminous (LX ≈ 5 × 1042 erg s−1) X-ray source at the nucleus of FRB 20190608B’s host, for which we infer an SMBH mass of MBH ∼ 108 M☉ and an Eddington ratio Lbol /LEdd ≈ 0.02, characteristic of geometrically thin disks in Seyfert galaxies. We also report nebular emission line fluxes for 24 highly secure FRB hosts (including 10 hosts for the first time), and assess their placement on a BPT diagram, finding that FRB hosts trace the underlying galaxy population. We further find that the hosts of repeating FRBs are not confined to the star-forming locus, contrary to previous findings. Finally, we place constraints on associated X-ray counterparts to FRBs in the context of ultraluminous X-ray sources (ULXs), and find that existing X-ray limits for FRBs rule out ULXs brighter than LX 1040 erg s−1. Leveraging the CHIME/FRB catalog and existing ULX catalogs, we search for spatially coincident ULX-FRB pairs. We identify a total of 28 ULXs spatially coincident with the localization regions for 17 FRBs, but find that the DM-inferred redshifts for the FRBs are inconsistent with the ULX redshifts, disfavoring an association between these specific ULX-FRB pairs. Copyright © 2023, The Authors. All rights reserved.

关键词： Active Galactic Nuclei

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UNCOVER: A NIRSpec Census of Lensed Galaxies at z = 8.50-13.08 Probing a High AGN Fraction and Ionized Bubbles in the Shadow

arXiv

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arXiv 2023年

作者： Fujimoto, Seiji Wang, Bingjie Weaver, John R. Kokorev, Vasily Atek, Hakim Bezanson, Rachel Labbe, Ivo Brammer, Gabriel Greene, Jenny E. Chemerynska, Iryna Dayal, Pratika de Graaff, Anna Furtak, Lukas J. Oesch, Pascal A. Setton, David J. Price, Sedona H. Miller, Tim B. Williams, Christina C. Whitaker, Katherine E. Zitrin, Adi Cutler, Sam E. Leja, Joel Pan, Richard Coe, Dan van Dokkum, Pieter Feldmann, Robert Fudamoto, Yoshinobu Goulding, Andy D. Khullar, Gourav Marchesini, Danilo Maseda, Michael Nanayakkara, Themiya Nelson, Erica J. Smit, Renske Stefanon, Mauro Weibel, Andrea Department of Astronomy The University of Texas at Austin AustinTX78712 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 University of Massachusetts AmherstMA01003 United States Kapteyn Astronomical Institute University of Groningen Groningen9700 AV Netherlands Institut d'Astrophysique de Paris CNRS Sorbonne Université 98bis Boulevard Arago Paris75014 France Department of Physics and Astronomy PITT PACC University of Pittsburgh PittsburghPA15260 United States Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia Niels Bohr Institute University of Copenhagen Jagtvej 128 København NDK-2200 Denmark Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany Physics Department Ben-Gurion University of the Negev P.O. Box 653 Be'er-Sheva84105 Israel Department of Astronomy University of Geneva Chemin Pegasi 51 Versoix1290 Switzerland Department of Astronomy Yale University New HavenCT06511 United States Department of Physics and Astronomy Northwestern University 1800 Sherman Ave EvanstonIL60201 United States 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 Physics and Astronomy Tufts University 574 Boston Ave. MedfordMA02155 United States 3700 San Martin Drive BaltimoreMD21218 United States United States Center for Astrophysical Sciences Department of Physics

We present JWST NIRSpec prism spectroscopy of lensed galaxies at z 9 found behind the massive galaxy cluster Abell 2744 in the UNCOVER Cycle 1 Treasury Program. We confirm the redshift via emission lines and/or the Lyα break for ten galaxies at z = 8.50-13.08 down to MUV = −17.3. We achieve a 100% confirmation rate for z > 9 candidates reported in Atek et al. (2023b). Using six sources with multiple line detections, we find that offsets in redshift estimates between the lines and the Lyα break alone can be ±0.2, raising caution in designing future follow-up spectroscopy for the break-only sources. With spec-z confirmed sources in UNCOVER and literature, we derive lower limits on the rest-frame ultraviolet (UV) luminosity function (LF) at z 9-12 and find that these lower limits agree with recent photometric measurements. We identify at least two unambiguous and several possible active galactic nucleus (AGN) systems based on X-ray, broad Hβ, high ionization lines (e.g., N iv] λ1487, C iv λ1549), and excess in UVLF. This requires the AGN LFs at z 9-10 to be comparable or even higher than the X-ray AGN LF estimated at z ∼ 6 and suggests a plausible cause of the high abundance of z > 9 galaxies claimed in the recent photometric measurements is AGNs. One UV-luminous source is confirmed at the same redshift as a broad-line AGN at z = 8.50 with a physical separation of 380 kpc in the source plane. These two sources show the emission blueward of Lyα, indicating a giant ionized bubble enclosing them with a radius of 7.69 ± 0.18 pMpc. Our results imply that AGNs have a non-negligible contribution to cosmic reionization. © 2023, CC BY.

关键词： Cosmology

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Exploring higher order images with Fe Ka-lines from relativistic disks: Black hole spin determination and bias

arXiv

引用

arXiv 2021年

作者： Falanga, M. Bakala, P. La Placa, R. De Falco, V. De Rosa, A. Stella, L. Hallerstrasse 6 Bern3012 Switzerland Research Centre for Computational Physics and Data Processing Silesian University in Opava Bezrucovo nám. 13 OpavaCZ-746 01 Czech Republic M. R. Stefánik Observatory and Planetarium Sládkovicova 41 Hlohovec920 01 Slovakia 00078 Italy Dipartimento di Fisica Università di Roma Tor Vergata Via della Ricerca Scientifica Roma00133 Italy Dipartimento di Fisica Università La Sapienza Piazzale Aldo Moro 5 Roma00185 Italy INAF - Istituto di Astrofisica e Planetologie Spaziali Via Fosso del Cavaliere Roma00133 Italy

We study the contributions to the relativistic Fe Kaline profile from higher order images (HOIs) produced by strongly deflected rays from the disk which cross the plunging region, located between the innermost stable circular orbit (ISCO) radius and the event horizon of a Kerr black hole. We investigate the characteristics features imprinted by the HOIs in the line profile for different black hole spins, disk emissivity laws and inclinations. We find that they extend from the red wing of the profile up to energies slightly lower than those of the blue peak, adding - 0.4-1.3% to the total line flux. The contribution to the specific flux is often in the - 1% to 7% range, with the highest values attained for low and negative spin (α ≥ 0.3) black holes surrounded by intermediate inclination angle (i - 40°) disks. We simulate future observations of a black hole X-ray binary system with the Large Area Detector of the planned X-ray astronomy enhanced X-ray Timing and Polarimetry Mission (eXTP) and find that the Fe Kaline profiles of systems accreting at ≥ 1% the Eddington rate are affected by the HOI features for a range of parameters. This would provide evidence of the extreme gravitational lensing of HOI rays. Our simulations show also that not accounting for HOI contributions to the Fe Kaline profile may systematically bias measurements of the black hole spin parameter towards values higher by up to - 0.3 than the inputted ones. Copyright © 2021, The Authors. All rights reserved.

关键词： Stars

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Galactic transient sources with the Cherenkov Telescope Array Observatory

引用

Monthly Notices of the Royal Astronomical Society 2025年第1期540卷 205–238页

作者： Abe, K Abe, S Abhir, J Abhishek, A Acero, F Acharyya, A Adam, R Aguasca-Cabot, A Agudo, I Aguirre-Santaella, A Alfaro, J Alfaro, R Alvarez-Crespo, N Alves Batista, R Amans, J-P Amato, E Ambrosi, G Ambrosino, F Angüner, E O Antonelli, L A Aramo, C Arcaro, C Arnesen, T T H Asano, K Ascasibar, Y Aschersleben, J Ashkar, H Augusto Stuani, L Baack, D Backes, M Balazs, C Balbo, M Baquero Larriva, A Barbosa Martins, V Barres de Almeida, U Barrio, J A Barrios-Jiménez, L Batković, I Batzofin, R Baxter, J Becerra González, J Becker Tjus, J Belmont, R Benbow, W Bernete, J Bernlöhr, K Berti, A Bertucci, B Beshley, V Bhattacharjee, P Bhattacharyya, S Bigongiari, C Bissaldi, E Blanch, O Blazek, J Bocchino, F Boisson, C Bolmont, J Bonnoli, G Bonollo, A Bordas, P Bosnjak, Z Bottacini, E Böttcher, M Bradascio, F Bronzini, E Brown, A M Brunelli, G Bulgarelli, A Burelli, I Burger-Scheidlin, C Burmistrov, L Burton, M Buscemi, M Cailleux, J Campoy-Ordaz, A Cantlay, B K Capasso, G Caproni, A Capuzzo-Dolcetta, R Caraveo, P Caroff, S Carosi, A Carosi, R Carquin, E Carrasco, M-S Cascone, E Cassol, F Castaldini, L Castrejon, N Castro-Tirado, A J Cerasole, D Ceribella, G Cerruti, M Chadwick, P M Chaty, S Chen, A W Chernyakova, M Chiavassa, A Chudoba, J Chytka, L Cicciari, G M Cifuentes, A Coimbra Araujo, C H Colapietro, M Conforti, V Contreras, J L Cortina, J Costa, A Costantini, H Cotter, G Cristofari, P Cuevas, O Curtis-Ginsberg, Z D’Aì, A D’Amico, G D’Ammando, F Dai, S Dazzi, F de Bony de Lavergne, M De Caprio, V De Cesare, G De Frondat Laadim, F de Gouveia Dal Pino, E M De Lotto, B De Lucia, M de Martino, D de Menezes, R de Naurois, M de Ona Wilhelmi, E de Souza, V del Peral, L del Valle, M V Delgado, C Dell’aiera, M Della Valle, M della Volpe, D Depaoli, D Devin, J Di Girolamo, T Di Piano, A Di Pierro, F Di Tria, R Di Venere, L Diebold, S Dignam, C Dima, R Dinesh, A Djuvsland, J Dominik, R M Dominis Prester, D Donini, A Dorner, D Dörner, J Doro, M Dubos, C Ducci, L Dwarkadas, V V Ebr, J Eckner, C Egberts, K Einecke, S Elsässer, D Emery Department of Physics Tokai University 4-1-1 Kita-Kaname Hiratsuka Kanagawa 259-1292 Japan Institute for Cosmic Ray Research University of Tokyo 5-1-5 Kashiwa-no-ha Kashiwa Chiba 277-8582 Japan ETH Zürich Institute for Particle Physics and Astrophysics Otto-Stern-Weg 5 CH-8093 Zürich Switzerland INFN and Università degli Studi di Siena Dipartimento di Scienze Fisiche della Terra e dell’Ambiente (DSFTA) Sezione di Fisica Via Roma 56 I-53100 Siena Italy Université Paris-Saclay Université Paris Cité CEA CNRS AIM F-91191 Gif-sur-Yvette Cedex France FSLAC IRL 2009 CNRS/IAC E-38205 La Laguna Tenerife Spain University of Alabama Tuscaloosa Department of Physics and Astronomy Gallalee Hall Box 870324 Tuscaloosa AL 35487-0324 USA Université Côte d’Azur Observatoire de la Côte d’Azur CNRS Laboratoire Lagrange UF 06304 Nice France Laboratoire Leprince-Ringuet CNRS/IN2P3 École Polytechnique Institut Polytechnique de Paris F-91120 Palaiseau France Departament de Física Quàntica i Astrofísica Institut de Ciències del Cosmos Universitat de Barcelona IEEC-UB Martí i Franquès 1 E-08028 Barcelona Spain Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n E-18008 Granada Spain Institute for Computational Cosmology and Department of Physics Durham University South Road Durham DH1 3LE UK Pontificia Universidad Católica de Chile Av. Libertador Bernardo O’Higgins 340 8331150 Santiago Chile Universidad Nacional Autónoma de México Delegación Coyoacán 04510 Ciudad de México Mexico IPARCOS-UCM Instituto de Física de Partículas y del Cosmos and EMFTEL Department Universidad Complutense de Madrid E-28040 Madrid Spain Instituto de Física Teórica UAM/CSIC and Departamento de Física Teórica Universidad Autónoma de Madrid c/ Nicolás Cabrera 13-15 Campus de Cantoblanco UAM E-28049 Madrid Spain LUTH GEPI and LERMA Observatoire de Paris Université PSL Université Paris Cité CNRS 5 place Jules Janssen F-92190 Meudon France INAF – Osservatorio

A wide variety of Galactic sources show transient emission at soft and hard X-ray energies: low- and high-mass X-ray binaries containing compact objects, isolated neutron stars exhibiting extreme variability as magnetars as well as pulsar-wind nebulae. Although most of them can show emission up to MeV and/or GeV energies, many have not yet been detected in the TeV domain by Imaging Atmospheric Cherenkov Telescopes. In this paper, we explore the feasibility of detecting new Galactic transients with the Cherenkov Telescope Array Observatory (CTAO) and the prospects for studying them with Target of Opportunity observations. We show that CTAO will likely detect new sources in the TeV regime, such as the massive microquasars in the Cygnus region, low-mass X-ray binaries with low-viewing angle, flaring emission from the Crab pulsar-wind nebula or other novae explosions, among others. Since some of these sources could also exhibit emission at larger time-scales, we additionally test their detectability at longer exposures. We finally discuss the multiwavelength synergies with other instruments and large astronomical facilities.

关键词： binaries: general stars: magnetars novae cataclysmic variables pulsars: general gamma-rays: general

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Disks in Nearby Young Stellar Associations Found Via Virtual Reality

arXiv

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arXiv 2022年

作者： Higashio, Susan Kuchner, Marc J. Silverberg, Steven M. Brandt, Matthew A. Grubb, Thomas G. Gagné, Jonathan Debes, John H. Schlieder, Joshua Wisniewski, John P. Slocum, Stewart Bans, Alissa S. Bhattacharjee, Shambo Biggs, Joseph R. Bosch, Milton K.D. Cernohous, Tadeas Doll, Katharina Luca, Hugo A. Durantini Enachioaie, Alexandru Griffith, Phillip Hamilton, Joshua Holden, Jonathan Hyogo, Michiharu Jung, Dawoon Lau, Lily Piñeiro, Fernanda Piipuu, Art Stiller, Lisa Nasa Goddard Space Flight Center Exoplanets and Stellar Astrophysics Laboratory Code 667 GreenbeltMD20771 United States Center for Research and Exploration in Space Science and Technology NASA/GSFC GreenbeltMD20771 United States Mit Kavli Institute United States Nasa Goddard Space Flight Center Science Data Processing Branch Code 587 GreenbeltMD20771 United States Planétarium Rio Tinto Alcan Espace Pour la Vie 4801 av. Pierre-de Coubertin MontrealQC Canada Institute for Research on Exoplanets Université de Montréal Département de Physique C.P. 6128 Succ. Centre-ville MontrealQCH3C 3J7 Canada Space Telescope Science Institute 3700 San Martin Dr. BaltimoreMD21218 United States Homer L. Dodge Department of Physics and Astronomy University of Oklahoma 440 W. Brooks Street NormanOK73019 United States Department of Computer Science Johns Hopkins University United States Department of Physics Emory University 201 Dowman Drive AtlantaGA30322 United States French National Centre for Scientific Research France Disk Detective IATE-OAC Universidad Nacional de Córdoba-CONICET Laprida 854 CórdobaX5000 BGR Argentina Meisei University 2-1-1 Hodokubo Tokyo Hino191-0042 Japan

The Disk Detective citizen science project recently released a new catalog of disk candidates found by visual inspection of images from NASA's Wide-Field Infrared Survey Explorer (WISE) mission and other surveys. We applied this new catalog of well-vetted disk candidates to search for new members of nearby young stellar associations (YSAs) using a novel technique based on Gaia data and virtual reality (VR). We examined AB Doradus, Argus, β Pictoris, Carina, Columba, Octans-Near, TucanaHorologium, and TW Hya by displaying them in VR together with other nearby stars, color-coded to show infrared excesses found via Disk Detective. Using this method allows us to find new association members in mass regimes where isochrones are degenerate. We propose ten new YSA members with infrared excesses: three of AB Doradus (HD 44775, HD 40540 and HD 44510), one of β Pictoris (HD 198472), two of Octans-Near (HD 157165 and BD+35 2953), and four disk-hosting members of a combined population of Carina, Columba and Tucana-Horologium: CPD-57 937, HD 274311, HD 41992, and WISEA J092521.90-673224.8. This last object (J0925) appears to be an extreme debris disk with a fractional infrared luminosity of 3.7 × 10-2. We also propose two new members of AB Doradus that do not show infrared excesses: TYC 6518-1857-1 and CPD-25 1292. We find HD 15115 appears to be a member of Tucana-Horologium rather than β Pictoris. We advocate for membership in Columba-Carina of HD 30447, CPD-35 525, and HD 35841. Finally, we propose that three M dwarfs, previously considered members of Tuc-Hor are better considered a separate association, tentatively called "Smethells 165". © 2022, CC BY.

关键词： Stars

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New Limit for Neutrinoless Double-Beta Decay of Mo100 from the CUPID-Mo Experiment

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Physical Review Letters 2021年第18期126卷 181802-181802页

作者： E. Armengaud C. Augier A. S. Barabash F. Bellini G. Benato A. Benoît M. Beretta L. Bergé J. Billard Yu. A. Borovlev Ch. Bourgeois V. B. Brudanin P. Camus L. Cardani N. Casali A. Cazes M. Chapellier F. Charlieux D. Chiesa M. de Combarieu I. Dafinei F. A. Danevich M. De Jesus T. Dixon L. Dumoulin K. Eitel F. Ferri B. K. Fujikawa J. Gascon L. Gironi A. Giuliani V. D. Grigorieva M. Gros E. Guerard D. L. Helis H. Z. Huang R. Huang J. Johnston A. Juillard H. Khalife M. Kleifges V. V. Kobychev Yu. G. Kolomensky S. I. Konovalov A. Leder P. Loaiza L. Ma E. P. Makarov P. de Marcillac R. Mariam L. Marini S. Marnieros D. Misiak X.-F. Navick C. Nones E. B. Norman V. Novati E. Olivieri J. L. Ouellet L. Pagnanini P. Pari L. Pattavina B. Paul M. Pavan H. Peng G. Pessina S. Pirro D. V. Poda O. G. Polischuk S. Pozzi E. Previtali Th. Redon A. Rojas S. Rozov C. Rusconi V. Sanglard J. A. Scarpaci K. Schäffner B. Schmidt Y. Shen V. N. Shlegel B. Siebenborn V. Singh C. Tomei V. I. Tretyak V. I. Umatov L. Vagneron M. Velázquez B. Welliver L. Winslow M. Xue E. Yakushev M. Zarytskyy A. S. Zolotarova IRFU CEA Université Paris-Saclay F-91191 Gif-sur-Yvette France Univ Lyon Université Lyon 1 CNRS/IN2P3 IP2I-Lyon F-69622 Villeurbanne France National Research Centre Kurchatov Institute Institute of Theoretical and Experimental Physics 117218 Moscow Russia Dipartimento di Fisica Sapienza Università di Roma Piazzale Aldo Moro 2 I-00185 Rome Italy INFN Sezione di Roma Piazzale Aldo Moro 2 I-00185 Rome Italy INFN Laboratori Nazionali del Gran Sasso I-67100 Assergi (AQ) Italy CNRS-Néel 38042 Grenoble Cedex 9 France University of California Berkeley California 94720 USA Université Paris-Saclay CNRS/IN2P3 IJCLab 91405 Orsay France Nikolaev Institute of Inorganic Chemistry 630090 Novosibirsk Russia Laboratory of Nuclear Problems JINR 141980 Dubna Moscow region Russia Dipartimento di Fisica Università di Milano-Bicocca I-20126 Milano Italy INFN Sezione di Milano-Bicocca I-20126 Milano Italy IRAMIS CEA Université Paris-Saclay F-91191 Gif-sur-Yvette France Institute for Nuclear Research of NASU 03028 Kyiv Ukraine Karlsruhe Institute of Technology Institute for Astroparticle Physics 76021 Karlsruhe Germany Lawrence Berkeley National Laboratory Berkeley California 94720 USA Key Laboratory of Nuclear Physics and Ion-beam Application (MOE) Fudan University Shanghai 200433 People’s Republic of China Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Karlsruhe Institute of Technology Institute for Data Processing and Electronics 76021 Karlsruhe Germany INFN Gran Sasso Science Institute I-67100 L’Aquila Italy Physik Department Technische Universität München Garching D-85748 Germany Department of Modern Physics University of Science and Technology of China Hefei 230027 People’s Republic of China LSM Laboratoire Souterrain de Modane 73500 Modane France Department of Physics and Astronomy University of South Carolina Columbia South Carolina 29208 USA Université Grenoble Alpes CNRS Grenoble INP SIMAP 38402 Saint Martin d’Héres Fr

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νββ experiment. It consists of a 4.2 kg array of 20 enriched Li2Mo100O4 scintillating bolometers to search for the lepton-number-violating process of 0νββ decay in Mo100. With more than one year of operation (Mo100 exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νββ is observed. We report a new limit on the half-life of 0νββ decay in Mo100 of T1/2>1.5×1024 yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨mββ⟩<(0.31–0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

关键词： Neutrinoless double beta decay Nuclear structure & decays Majorana neutrinos Neutrinos

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Revisiting the classics: On the evolutionary origin of the "Fe II" and "He/N" spectral classes of novae

arXiv

引用

arXiv 2023年

作者： Aydi, E. Chomiuk, L. Strader, J. Sokolovsky, K.V. Williams, R.E. Buckley, D.A.H. Ederoclite, A. Izzo, L. Kyer, R. Linford, J.D. Kniazev, A. Metzger, B.D. Mikolajewska, J. Molaro, P. Molina, I. Mukai, K. Munari, U. Orio, M. Panurach, T. Shappee, B.J. Shen, K.J. Sokoloski, J.L. Urquhart, R. Walter, F.M. Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States Department of Astronomy University of Illinois at Urbana-Champaign 1002 W. Green Street UrbanaIL61801 United States Sternberg Astronomical Institute Moscow State University Universitetskii pr. 13 Moscow119992 Russia Department of Astronomy & Astrophysics University of California Santa Cruz 1156 High Street Santa CruzCA95064 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States South African Astronomical Observatory P.O. Box 9 Observatory7935 South Africa Department of Astronomy University of Cape Town Private Bag X3 Rondebosch7701 South Africa Centro de Estudios de Física del Cosmos de Aragón Plaza San Juan 1 Teruel44001 Spain UK Astronomy Technology Centre Royal Observatory Blackford Hill EdinburghEH9 3HJ United Kingdom DARK Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen Ø2200 Denmark National Radio Astronomy Observatory P.O. Box O SocorroNM87801 United States Southern African Large Telescope Foundation PO Box 9 Observatory7935 South Africa Special Astrophysical Observatory Nizhnij Arkhyz Karachai-Circassia 369167 Russia Department of Physics Columbia Astrophysics Laboratory Columbia University New YorkNY10027 United States Center for Computational Astrophysics Flatiron Institute 162 5th Ave New YorkNY10010 United States Nicolaus Copernicus Astronomical Center Polish Academy of Sciences Bartycka 18 WarsawPL 00-716 Poland INAF-Osservatorio Astronomico di Trieste Via G.B. Tiepolo 11 TriesteI-34143 Italy Institute of Fundamental Physics of the Universe Via Beirut 2 Miramare Trieste Italy CRESST and X-ray Astrophysics Laboratory NASA GSFC GreenbeltMD20771 United States Department of Physics University of Maryland Baltimore County 1000 Hilltop Circle BaltimoreMD21250 United States INAF Astronomical Obs

The optical spectra of novae are characterized by emission lines from the hydrogen Balmer series and either Fe II or He/N, leading to their traditional classification into two spectral classes: "Fe II" and "He/N". For decades, the origins of these spectral features were discussed in the literature in the contexts of different bodies of gas or changes in the opacity of the ejecta, particularly associated with studies by R. E. Williams and S. N. Shore. Here, we revisit these major studies with dedicated, modern data sets, covering the evolution of several novae from early rise to peak all the way to the nebular phase. Our data confirm previous suggestions in the literature that the "Fe II" and "He/N" spectral classes are phases in the spectroscopic evolution of novae driven primarily by changes in the opacity, ionization, and density of the ejecta, and most if not all novae go through at least three spectroscopic phases as their eruptions evolve: an early He/N (phase 1;observed during the early rise to visible peak and characterized by P Cygni lines of He I and N II/III), then an Fe II (phase 2;observed near visible peak and characterized by P Cygni lines of Fe II and O I), and then a later He/N (phase 3;observed during the decline and characterized by emission lines of He I/II, N II/III), before entering the nebular phase. This spectral evolution seems to be ubiquitous across novae, regardless of their speed class;however the duration of each of these phases differs based on the speed class of the nova. © 2023, CC BY-NC-ND.

关键词： Opacity

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The Obscured Fraction of Quasars at Cosmic Noon

arXiv

引用

arXiv 2022年

作者： Vijarnwannaluk, Bovornpratch Akiyama, Masayuki Schramm, Malte Ueda, Yoshihiro Matsuoka, Yoshiki Toba, Yoshiki Sawicki, Marcin Gwyn, Stephen Pflugradt, Janek Astronomical Institute Tohoku University Aoba-ku Aramaki Miyagi Sendai980-8578 Japan Graduate School of Science and Engineering Saitama University 255 Shimo-Okubo Sakura-ku Saitama Saitama City338-8570 Japan Department of Astronomy Kyoto University Kitashirakawa-Oiwake-cho Sakyo-ku Kyoto606-8502 Japan Research Center for Space and Cosmic Evolution Ehime University 2-5 Bunkyo-cho Ehime Matsuyama790-8577 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Tokyo Mitaka181-8588 Japan Institute for Computational Astrophysics Department of Astronomy and Physics Saint Mary's University HalifaxNSB3H 3C3 Canada Canadian Astronomy Data Centre NRC-Herzberg 5071 West Saanich Road VictoriaBCV9E 2E7 Canada

Statistical studies of X-ray selected Active Galactic Nuclei (AGN) indicate that the fraction of obscured AGN increases with increasing redshift, and the results suggest that a significant part of the accretion growth occurs behind obscuring material in the early universe. We investigate the obscured fraction of highly accreting X-ray AGN at around the peak epoch of supermassive black hole growth utilizing the wide and deep X-ray and optical/IR imaging datasets. A unique sample of luminous X-ray selected AGNs above z > 2 was constructed by matching the XMM-SERVS X-ray point-source catalog with a PSF-convolved photometric catalog covering from u∗to 4.5μm bands. Photometric redshift, hydrogen column density, and 2-10 keV AGN luminosity of the X-ray selected AGN candidates were estimated. Using the sample of 306 2-10 keV detected AGN at above redshift 2, we estimate the fraction of AGN with log NH(cm-2) > 22, assuming parametric X-ray luminosity and absorption functions. The results suggest that 76-3+4% of luminous quasars (log LX(erg s-1) > 44.5) above redshift 2 are obscured. The fraction indicates an increased contribution of obscured accretion at high redshift than that in the local universe. We discuss the implications of the increasing obscured fraction with increasing redshift based on the AGN obscuration scenarios, which describe obscuration properties in the local universe. Both the obscured and unobscured z > 2 AGN show a broad range of SEDs and morphology, which may reflect the broad variety of host galaxy properties and physical processes associated with the obscuration. © 2022, CC BY.

关键词： Active Galactic Nuclei

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Machine Learning for Mini-EUSO Telescope data Analysis

arXiv

引用

arXiv 2023年

作者： Bertaina, Mario Zotov, Mikhail Anzhiganov, Dmitry Barghini, Dario Blaksley, Carl Coretti, Antonio Giulio Kryazhenkov, Aleksandr Montanaro, Antonio Olivi, Leonardo Abe, S. Adams, J.H. Allard, D. Alldredge, P. Aloisio, R. Anchordoqui, L. Anzalone, A. Arnone, E. Bagheri, M. Baret, B. Barghini, D. Battisti, M. Bellotti, R. Belov, A.A. Bertaina, M. Bertone, P.F. Bianciotto, M. Bisconti, F. Blaksley, C. Blin-Bondil, S. Bolmgren, K. Briz, S. Burton, J. Cafagna, F. Cambié, G. Campana, D. Capel, F. Caruso, R. Casolino, M. Cassardo, C. Castellina, A. Černý, K. Christl, M.J. Colalillo, R. Conti, L. Cotto, G. Crawford, H.J. Cremonini, R. Creusot, A. Cummings, A. de Castro Gónzalez, A. de la Taille, C. Diesing, R. Dinaucourt, P. Di Nola, A. Ebisuzaki, T. Eser, J. Fenu, F. Ferrarese, S. Filippatos, G. Finch, W.W. Flaminio, F. Fornaro, C. Fuehne, D. Fuglesang, C. Fukushima, M. Gadamsetty, S. Gardiol, D. Garipov, G.K. Gazda, E. Golzio, A. Guarino, F. Guépin, C. Haungs, A. Heibges, T. Isgrò, F. Judd, E.G. Kajino, F. Kaneko, I. Kim, S.-W. Klimov, P.A. Krizmanic, J.F. Kungel, V. Kuznetsov, E. Martínez, F. López Mandát, D. Manfrin, M. Marcelli, A. Marcelli, L. Marszal, W. Matthews, J.N. Mese, M. Meyer, S.S. Mimouni, J. Miyamoto, H. Mizumoto, Y. Monaco, A. Nagataki, S. Nachtman, J.M. Naumov, D. Neronov, A. Nonaka, T. Ogawa, T. Ogio, S. Ohmori, H. Olinto, A.V. Onel, Y. Osteria, G. Otte, A.N. Pagliaro, A. Panico, B. Parizot, E. Park, I.H. Paul, T. Pech, M. Perfetto, F. Picozza, P. Piotrowski, L.W. Plebaniak, Z. Posligua, J. Potts, M. Prevete, R. Prévôt, G. Przybylak, M. Reali, E. Reardon, P. Reno, M.H. Ricci, M. Matamala, O.F. Romero Romoli, G. Sagawa, H. Sakaki, N. Saprykin, O.A. Sarazin, F. Sato, M. Schovánek, P. Scotti, V. Selmane, S. Sharakin, S.A. Shinozaki, K. Stepanoff, S. Soriano, J.F. Szabelski, J. Tajima, N. Tajima, T. Takahashi, Y. Takeda, M. Takizawa, Y. Thomas, S.B. Tkachev, L.G. Tomida, T. Toscano, S. Dipartimento di Fisica Università di Torino Torino Italy INFN Sezione di Torino Torino Italy Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State University Moscow Russia Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State University Moscow Russia INAF Osservatorio astrofisico di Torino Torino Italy RIKEN Wako Japan Department of Electronics and Telecommunications Polytechnic University of Turin Corso Duca degli Abruzzi 24 Turin10129 Italy Algiers Algeria Univ. Constantine I Constantine Algeria Joint Laboratory of Optics Faculty of Science Palacký University Olomouc Czech Republic Institute of Physics of the Czech Academy of Sciences Prague Czech Republic Omega Ecole Polytechnique CNRS IN2P3 Palaiseau France Université de Paris CNRS AstroParticule et Cosmologie ParisF-75013 France France Germany Max Planck Institute for Physics Munich Germany Istituto Nazionale di Fisica Nucleare - Sezione di Bari Italy Università degli Studi di Bari Aldo Moro Italy Dipartimento di Fisica e Astronomia "Ettore Majorana" Università di Catania Italy Istituto Nazionale di Fisica Nucleare - Sezione di Catania Italy Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati Italy Istituto Nazionale di Fisica Nucleare - Sezione di Napoli Italy Università di Napoli Federico II Dipartimento di Fisica "Ettore Pancini" Italy INAF - Istituto di Astrofisica Spaziale e Fisica Cosmica Palermo Italy Istituto Nazionale di Fisica Nucleare - Sezione di Roma Tor Vergata Italy Università di Roma Tor Vergata - Dipartimento di Fisica Roma Italy Istituto Nazionale di Fisica Nucleare - Sezione di Torino Italy Dipartimento di Fisica Università di Torino Italy Osservatorio Astrofisico di Torino Istituto Nazionale di Astrofisica Italy Uninettuno University Rome Italy Agenzia Spaziale Italiana Via del Politecnico Roma00133 Italy Gran Sasso Science Institute L’Aquila Italy Institute for Cosmic Ray Research University of Tokyo Kashiwa Ja

Neural networks as well as other methods of machine learning (ML) are known to be highly efficient in different classification tasks, including classification of images and videos. Mini-EUSO is a wide-field-of-view imaging telescope that operates onboard the International Space Station since 2019 collecting data on miscellaneous processes that take place in the atmosphere of Earth in the UV range. Here we briefly present our results on the development of ML-based approaches for recognition and classification of track-like signals in the Mini-EUSO data, among them meteors, space debris and signals the light curves and kinematics of which are similar to those expected from extensive air showers generated by ultra-high-energy cosmic rays. We show that even simple neural networks demonstrate impressive performance in solving these tasks. © 2023, CC BY.

关键词： Machine learning

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