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NEID Rossiter-McLaughlin Measurement of TOI-1268b: A Young Warm Saturn Aligned with Its Cool Host Star

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arXiv 2022年

作者： Dong, Jiayin Huang, Chelsea X. Zhou, George Dawson, Rebekah I. Stefánsson, Gudmundur K. Bender, Chad F. Blake, Cullen H. Ford, Eric B. Halverson, Samuel Kanodia, Shubham Mahadevan, Suvrath McElwain, Michael W. Ninan, Joe P. Robertson, Paul Arpita, R.O.Y. Schwab, Christian Stevens, Daniel J. Terrien, Ryan C. Vanderburg, Andrew Kraus, Adam L. Douglas, Stephanie Newton, Elisabeth Rampalli, Rayna Krolikowski, Daniel M. Collins, Karen A. Rodriguez, Joseph E. Feliz, Dax L. Srdoc, Gregor Ziegler, Carl Barkaoui, Khalid Pozuelos, Francisco J. Jehin, Emmanuel Michaël, C. Benkhaldoun, Zouhair Lewin, Pablo Forés-Toribio, Raquel Muñoz, Jose A. McLeod, Kim K. Özyurt, Fiona Powers Horta, Ferran Grau Murgas, Felipe Latham, David W. Quinn, Samuel N. Bieryla, Allyson Howell, Steve B. Gnilka, Crystal L. Ciardi, David R. Lund, Michael B. Dressing, Courtney D. Giacalone, Steven Savel, Arjun B. Strakhov, Ivan A. Belinski, Alexander A. Ricker, George R. Seager, S. Winn, Joshua N. Jenkins, Jon M. Torres, Guillermo Paegert, Martin Department of Astronomy & Astrophysics 525 Davey Laboratory The Pennsylvania State University University ParkPA16802 United States Center for Exoplanets and Habitable Worlds 525 Davey Laboratory The Pennsylvania State University University ParkPA16802 United States University of Southern Queensland Centre for Astrophysics West Street ToowoombaQLD4350 Australia Department of Physics Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Institute for Computational and Data Sciences The Pennsylvania State University University ParkPA16802 United States Center for Astrostatistics 525 Davey Laboratory The Pennsylvania State University University ParkPA16802 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane Princeton NJ08540 United States Steward Observatory The University of Arizona 933 N. Cherry Ave TucsonAZ85721 United States Department of Physics and Astronomy University of Pennsylvania 209 S 33rd St PhiladelphiaPA19104 United States Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive PasadenaCA91109 United States Penn State Extraterrestrial Intelligence Center 525 Davey Laboratory The Pennsylvania State University University ParkPA16802 United States Exoplanets and Stellar Astrophysics Laboratory NASA Goddard Space Flight Center GreenbeltMD20771 United States Department of Physics & Astronomy The University of California Irvine IrvineCA92697 United States Space Telescope Science Institute 3700 San Martin Dr BaltimoreMD21218 United States Department of Physics and Astronomy Johns Hopkins University 3400 N Charles St BaltimoreMD21218 United States Department of Physics and Astronomy Macquarie University Balaclava Road North RydeNSW2109 Australia Carleton College One North College St. NorthfieldMN55057 United States Department of Astronomy The University of Texas at Austin AustinTX78712 U

Close-in gas giants present a surprising range of stellar obliquity, the angle between a planet's orbital axis and its host star's spin axis. It is unclear whether the obliquities reflect the planets' dynamical history (e.g., aligned for in situ formation or disk migration versus misaligned for high-eccentricity tidal migration) or whether other mechanisms (e.g., primordial misalignment or planet-star interactions) are more important in sculpting the obliquity distribution. Here we present the stellar obliquity measurement of TOI-1268 (TIC-142394656, Vmag∼10.9), a young K-type dwarf hosting an 8.2-day period, Saturn-sized planet. TOI-1268's lithium abundance and rotation period suggest the system age between the ages of Pleiades cluster (∼120 Myr) and Prasepe cluster (∼670 Myr). Using the newly commissioned NEID spectrograph, we constrain the stellar obliquity of TOI-1268 via the Rossiter-McLaughlin (RM) effect from both radial velocity (RV) and Doppler Tomography (DT) signals. The 3σ upper bounds of the projected stellar obliquity |λ| from both models are below 60◦. The large host star separation (a/R*∼17), combined with the system's young age, makes it unlikely that the planet has realigned its host star. The stellar obliquity measurement of TOI-1268 probes the architecture of a young gas giant beyond the reach of tidal realignment (a/R* 10) and reveals an aligned or slightly misaligned system. Copyright © 2022, The Authors. All rights reserved.

关键词： Extrasolar planets

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

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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

Evidence for X-ray emission in excess to the jet afterglow decay 3.5 yrs after the binary neutron star merger GW 170817: A new emission component

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arXiv 2021年

作者： Hajela, Aprajita Margutti, R. Bright, J.S. Alexander, K.D. Metzger, B.D. Nedora, V. Kathirgamaraju, A. Margalit, B. Radice, D. Guidorzi, C. Berger, E. Macfadyen, A. Giannios, D. Chornock, R. Heywood, I. Sironi, L. Gottlieb, O. Coppejans, D. Laskar, T. Cendes, Y. Barniol Duran, R. Eftekhari, T. Fong, W. McDowell, A. Nicholl, M. Xie, X. Zrake, J. Bernuzzi, S. Broekgaarden, F.S. Kilpatrick, C.D. Terreran, G. Villar, V.A. Blanchard, P.K. Gomez, S. Hosseinzadeh, G. Matthews, D.J. Rastinejad, J.C. Center for Interdisciplinary Exploration and Research in Astrophysics Department of Physics and Astronomy Northwestern University 2145 Sheridan Road Evanston IL60208-3112 United States Department of Astronomy University of California BerkeleyCA94720-3411 United States Department of Physics Columbia University New YorkNY10027 United States Center for Computational Astrophysics Flatiron Institute 162 W. 5th Avenue New YorkNY10011 United States Max Planck Institute for Gravitational Physics Albert Einstein Institute Am Mühlenberg 1 Potsdam14476 Germany Institute for Physics and Astronomy University of Potsdam Potsdam14476 Germany Division of Physics Mathematics and Astronomy California Institute of Technology PasadenaCA91125 United States Astronomy Department and Theoretical Astrophysics Center University of California Berkeley BerkeleyCA94720 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Department of Physics The Pennsylvania State University University ParkPA16802 United States Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Department of Physics and Earth Science University of Ferrara via Saragat 1 FerraraI-44122 Italy INFN - Sezione di Ferrara via Saragat 1 FerraraI-44122 Italy INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna Via Piero Gobetti 101 BolognaI-40129 Italy Center for Astrophysics Harvard & Smithsonian 60 Garden St. CambridgeMA02138 United States Center for Cosmology and Particle Physics Physics Department New York University New YorkNY10003 United States Department of Physics and Astronomy Purdue University West LafayetteIN47907 United States Department of Physics University of Oxford Keble Road OxfordOX1 3RH United Kingdom Department of Physics and Electronics Rhodes University PO Box 94 Makhanda 6140 South Africa South African Radio Astronomy

For the first ∼ 3 years after the binary neutron star merger event GW 170817 the radio and X-ray radiation has been dominated by emission from a structured relativistic off-axis jet propagating into a low-density medium with n −3. We report on observational evidence for an excess of X-ray emission at δt > 900 days after the merger. With Lx ≈ 5 × 1038 erg s−1 at 1234 days, the recently detected X-ray emission represents a ≥ 3.2 σ (Gaussian equivalent) deviation from the universal post jet-break model that best fits the multi-wavelength afterglow at earlier times. In the context of JetFit afterglow models, current data represent a departure with statistical significance ≥ 3.1 σ, depending on the fireball collimation, with the most realistic models showing excesses at the level of ≥ 3.7 σ. A lack of detectable 3 GHz radio emission suggests a harder broad-band spectrum than the jet afterglow. These properties are consistent with the emergence of a new emission component such as synchrotron radiation from a mildly relativistic shock generated by the expanding merger ejecta, i.e. a kilonova afterglow. In this context, we present a set of ab-initio numerical-relativity BNS merger simulations that show that an X-ray excess supports the presence of a high-velocity tail in the merger ejecta, and argues against the prompt collapse of the merger remnant into a black hole. Radiation from accretion processes on the compact-object remnant represents a viable alternative. Neither a kilonova afterglow nor accretion-powered emission have been observed before, as detections of BNS mergers at this phase of evolution are unprecedented. Copyright © 2021, The Authors. All rights reserved.

关键词： Merging

The UNCOVER Survey: A first-look HST+JWST catalog of 60, 000 galaxies near Abell 2744 and beyond

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arXiv 2023年

作者： Weaver, John R. Cutler, Sam E. Pan, Richard Whitaker, Katherine E. Labbé, Ivo Price, Sedona H. Bezanson, Rachel Brammer, Gabriel Marchesini, Danilo Leja, Joel Wang, Bingjie Furtak, Lukas J. Zitrin, Adi Atek, Hakim Chemerynska, Iryna Coe, Dan Dayal, Pratika van Dokkum, Pieter Feldmann, Robert Förster Schreiber, Natascha M. Franx, Marijn Fujimoto, Seiji Fudamoto, Yoshinobu Glazebrook, Karl de Graaff, Anna Greene, Jenny E. Juneau, Stéphanie Kassin, Susan Kriek, Mariska Khullar, Gourav Maseda, Michael V. Mowla, Lamiya A. Muzzin, Adam Nanayakkara, Themiya Nelson, Erica J. Oesch, Pascal A. Pacifici, Camilla Papovich, Casey Setton, David J. Shapley, Alice E. Shipley, Heath V. Smit, Renske Stefanon, Mauro Taylor, Edward N. Weibel, Andrea Williams, Christina C. Department of Astronomy University of Massachusetts AmherstMA01003 United States Department of Physics and Astronomy Tufts University 574 Boston Ave. MedfordMA02155 United States Denmark Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia 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 & 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 Physics Department Ben-Gurion University of the Negev P.O. Box 653 Beer-Sheva8410501 Israel Institut d’Astrophysique de Paris CNRS Sorbonne Université 98bis Boulevard Arago Paris75014 France 3700 San Martin Drive BaltimoreMD21218 United States United States Center for Astrophysical Sciences Department of Physics and Astronomy The Johns Hopkins University 3400 N Charles St. BaltimoreMD21218 United States Kapteyn Astronomical Institute University of Groningen P.O. Box 800 Groningen9700 AV Netherlands Department of Astronomy Yale University New HavenCT06511 United States Institute for Computational Science University of Zurich Winterhurerstrasse 190 ZurichCH-8057 Switzerland Max-Planck-Institut für extraterrestrische Physik Gießenbachstraße 1 Garching85748 Germany Leiden Observatory Leiden University P.O.Box 9513 LeidenNL-2300 AA Netherlands Department of Astronomy The University of Texas at Austin AustinTX78712 United States Waseda Research Institute for Science and Engineering Faculty of Science and Engineering Waseda University 3-4-1 Okubo Shinjuku Tokyo169-8555 Japan National Astronomical Observatory of Jap

In November 2022, the James Webb Space Telescope (JWST) returned deep near-infrared images of Abell 2744 – a powerful lensing cluster capable of magnifying distant, incipient galaxies beyond it. Together with the existing Hubble Space Telescope (HST) imaging, this publicly available dataset opens a fundamentally new discovery space to understand the remaining mysteries of the formation and evolution of galaxies across cosmic time. In this work, we detect and measure some 60 000 objects across the 49 arcmin2 JWST footprint down to a 5 σ limiting magnitude of ∼30 mag in 0.32′′ apertures. Photometry is performed using circular apertures on images matched to the point spread function of the reddest NIRCam broad band, F444W, and cleaned of bright cluster galaxies and the related intracluster light. To give an impression of the photometric performance, we measure photometric redshifts and achieve a σNMAD ≈ 0.03 based on known, but relatively small, spectroscopic samples. With this paper, we publicly release our HST and JWST PSF-matched photometric catalog with optimally assigned aperture sizes for easy use, along with single aperture catalogs, photometric redshifts, rest-frame colors, and individual magnification estimates. These catalogs will set the stage for efficient and deep spectroscopic follow-up of some of the first JWST-selected samples in Summer 2023. © 2023, CC BY.

关键词： Photometry

Why is the Winner the Best?

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Why is the Winner the Best?

Conference on Computer Vision and Pattern Recognition (CVPR)

作者： M. Eisenmann A. Reinke V. Weru M. D. Tizabi F. Isensee T. J. Adler S. Ali V. Andrearczyk M. Aubreville U. Baid S. Bakas N. Balu S. Bano J. Bernal S. Bodenstedt A. Casella V. Cheplygina M. Daum M. De Bruijne A. Depeursinge R. Dorent J. Egger D. G. Ellis S. Engelhardt M. Ganz N. Ghatwary G. Girard P. Godau A. Gupta L. Hansen K. Harada M. Heinrich N. Heller A. Hering A. Huaulmé P. Jannin A. E. Kavur O. Kodym M. Kozubek J. Li H. Li J. Ma C. Martín-Isla B. Menze A. Noble V. Oreiller N. Padoy S. Pati K. Payette T. Rädsch J. Rafael-Patiño V. Singh Bawa S. Speidel C. H. Sudre K. Van Wijnen M. Wagner D. Wei A. Yamlahi M. H. Yap C. Yuan M. Zenk A. Zia D. Zimmerer D. Aydogan B. Bhattarai L. Bloch R. Brüngel J. Cho C. Choi Q. Dou I. Ezhov C. M. Friedrich C. Fuller R. R. Gaire A. Galdran Á. García Faura M. Grammatikopoulou S. Hong M. Jahanifar I. Jang A. Kadkhodamohammadi I. Kang F. Kofler S. Kondo H. Kuijf M. Li M. Luu T. Martinčič P. Morais M. A. Naser B. Oliveira D. Owen S. Pang J. Park S. Park S. Płotka E. Puybareau N. Rajpoot K. Ryu N. Saeed A. Shephard P. Shi D. Štepec R. Subedi G. Tochon H. R. Torres H. Urien J. L. Vilaça K. A. Wahid H. Wang J. Wang L. Wang X. Wang B. Wiestler M. Wodzinski F. Xia J. Xie Z. Xiong S. Yang Y. Yang Z. Zhao K. Maier-Hein P. F. Jäger A. Kopp-Schneider L. Maier-Hein Division of Intelligent Medical Systems German Cancer Research Center (DKFZ) Heidelberg Germany Helmholtz Imaging German Cancer Research Center (DKFZ) Heidelberg Germany Faculty of Mathematics and Computer Science Heidelberg University Heidelberg Germany Division of Biostatistics German Cancer Research Center (DKFZ) Heidelberg Germany Division of Medical Image Computing German Cancer Research Center (DKFZ) Heidelberg Germany Faculty of Engineering and Physical Sciences School of Computing University of Leeds Leeds UK Institute of Informatics School of Management HES-SO Valais-Wallis University of Applied Sciences and Arts Western Switzerland Sierre Switzerland Department of Nuclear Medicine and Molecular Imaging Lausanne University Hospital Lausanne Switzerland Technische Hochschule Ingolstadt Ingolstadt Germany Center for Artificial Intelligence and Data Science for Integrated Diagnostics (AI2D) and Center for Biomedical Image Computing and Analytics (CBICA) University of Pennsylvania Philadelphia PA USA Department of Pathology and Laboratory Medicine Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Department of Radiology Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Department of Radiology University of Washington Seattle WA USA Department of Computer Science Wellcome/EPSRC Centre for Interventional and Surgical Sciences (WEISS) University College London London UK Universitat Autònoma de Barcelona & Computer Vision Center Barcelona Spain Division of Translational Surgical Oncology National Center for Tumor Diseases (NCT/UCC) Dresden Dresden Germany Department of Advanced Robotics Istituto Italiano di Tecnologia Italy Department of Electronics Information and Bioengineering Politecnico di Milano Milan Italy IT University of Copenhagen Copenhagen Denmark Department of General Visceral and Transplantation Surgery Heidelberg University Hospital Heidelberg Germany Department of Radiology and Nuc

International benchmarking competitions have become fundamental for the comparative performance assessment of image analysis methods. However, little attention has been given to investigating what can be learnt from these competitions. Do they really generate scientific progress? What are common and successful participation strategies? What makes a solution superior to a competing method? To address this gap in the literature, we performed a multicenter study with all 80 competitions that were conducted in the scope of IEEE ISBI 2021 and MICCAI 2021. Statistical analyses performed based on comprehensive descriptions of the submitted algorithms linked to their rank as well as the underlying participation strategies revealed common characteristics of winning solutions. These typically include the use of multi-task learning (63%) and/or multi-stage pipelines (61%), and a focus on augmentation (100%), image preprocessing (97%), data curation (79%), and post-processing (66%). The “typical” lead of a winning team is a computer scientist with a doctoral degree, five years of experience in biomedical image analysis, and four years of experience in deep learning. Two core general development strategies stood out for highly-ranked teams: the reflection of the metrics in the method design and the focus on analyzing and handling failure cases. According to the organizers, 43% of the winning algorithms exceeded the state of the art but only 11% completely solved the respective domain problem. The insights of our study could help researchers (1) improve algorithm development strategies when approaching new problems, and (2) focus on open research questions revealed by this work.

关键词：

A hot Mars-sized exoplanet transiting an M dwarf

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arXiv 2021年

作者： Cañas, Caleb I. Mahadevan, Suvrath Cochran, William D. Bender, Chad F. Feigelson, Eric D. Harman, C.E. Kopparapu, Ravi Kumar Caceres, Gabriel A. Diddams, Scott A. Endl, Michael Ford, Eric B. Halverson, Samuel Hearty, Fred Jones, Sinclaire Kanodia, Shubham Lin, Andrea S.J. Metcalf, Andrew J. Monson, Andrew Ninan, Joe P. Ramsey, Lawrence W. Robertson, Paul Roy, Arpita Schwab, Christian Stefánsson, Guðmundur Department of Astronomy & Astrophysics The Pennsylvania State University 525 Davey Laboratory University ParkPA16802 United States Center for Exoplanets and Habitable Worlds The Pennsylvania State University 525 Davey Laboratory University ParkPA16802 United States Center for Planetary Systems Habitability McDonald Observatory The University of Texas at Austin AustinTX78730 United States Steward Observatory The University of Arizona 933 N. Cherry Ave TucsonAZ85721 United States NASA Ames Research Center Moffett FieldCA94035 United States Planetary Environments Laboratory NASA Goddard Space Flight Center GreenbeltMD20771 United States Teachers Pay Teachers 111 East 18th St New YorkNY10003 United States Time and Frequency Division National Institute of Standards and Technology 325 Broadway BoulderCO80305 United States Department of Physics University of Colorado 2000 Colorado Avenue BoulderCO80309 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA16802 United States Center for Astrostatistics 525 Davey Lab The Pennsylvania State University University ParkPA16802 United States Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive PasadenaCA91109 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08540 United States Space Vehicles Directorate Air Force Research Laboratory 3550 Aberdeen Ave SE Kirtland AFBNM87117 United States Department of Physics & Astronomy The University of California Irvine IrvineCA92697 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Department of Physics and Astronomy Johns Hopkins University 3400 N Charles St BaltimoreMD21218 United States Department of Physics and Astronomy Macquarie University Balaclava Road North RydeNSW2109 Australia

We validate the planetary nature of an ultra-short period planet orbiting the M dwarf KOI-4777. We use a combination of space-based photometry from Kepler, high-precision, near-infrared Doppler spectroscopy from the Habitable-zone Planet Finder, and adaptive optics imaging to characterize this system. KOI-4777.01 is a Mars-sized exoplanet (Rp = 0.51 ± 0.03R⊕) orbiting the host star every 0.412-days (∼ 9.9-hours). This is the smallest validated ultra-short period planet known and we see no evidence for additional massive companions using our HPF RVs. We constrain the upper 3σ mass to Mp ⊕ by assuming the planet is less dense than iron. Obtaining a mass measurement for KOI-4777.01 is beyond current instrumental capabilities. © 2021, CC BY.

关键词： Extrasolar planets

Photodisintegration cross sections for resonant states and virtual states

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Physical Review C 2019年第3期99卷 034312-034312页

作者： Myagmarjav Odsuren Yuma Kikuchi Takayuki Myo Hiroshi Masui Kiyoshi Katō School of Engineering and Applied Sciences and Nuclear Research Center National University of Mongolia Ulaanbaatar 210646 Mongolia Tokuyama College National Institute of Technology Yamaguchi 745-8585 Japan Faculty of Engineering General Education Osaka Institute of Technology Osaka 535-8585 Japan Research Center for Nuclear Physics (RCNP) Osaka University Ibaraki 567-0047 Japan Information Processing Center Kitami Institute of Technology Kitami 090-8507 Japan Nuclear Reaction Data Centre Faculty of Science Hokkaido University Sapporo 060-0810 Japan

The s-wave photodisintegration cross sections observed just above the neutron breakup threshold energy are calculated for resonant and virtual states by using a complex-scaled two-body model, which simulates the Be9 nucleus with a Be8+ns-wave channel. We investigate the differences between behaviors of the resonance and virtual states in the photodisintegration cross sections near threshold energy in detail. It is shown that, in the present two-body model, resonant states very near the threshold energy produce a peak structure in the photodisintegration cross section that is similar that of the virtual state.

关键词： Energy levels & level densities Few-body systems Photonuclear reactions Resonance reactions 6 ≤ A ≤ 19

Classical novae at radio wavelengths

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arXiv 2021年

作者： Chomiuk, Laura Linford, Justin D. Aydi, Elias Bannister, Keith W. Krauss, Miriam I. Mioduszewski, Amy J. Mukai, Koji Nelson, Thomas J. Rupen, Michael P. Ryder, Stuart D. Sokoloski, Jennifer L. Sokolovsky, Kirill V. Strader, Jay Filipović, Miroslav D. Finzell, Tom Kawash, Adam Kool, Erik C. Metzger, Brian D. Nyamai, Miriam M. Ribeiro, Valério A.R.M. Roy, Nirupam Urquhart, Ryan Weston, Jennifer Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States National Radio Astronomy Observatory P.O. Box O SocorroNM87801 United States CSIRO Astronomy and Space Science PO Box 76 EppingNSW1710 Australia Pasadena City College 1570 E. Colorado Blvd. PasadenaCA91106 United States Center for Space Science and Technology University of Maryland Baltimore County BaltimoreMD21250 United States CRESST and X-ray Astrophysics Laboratory NASA/GSFC GreenbeltMD20771 United States Department of Physics and Astronomy University of Pittsburgh 3941 OHara St. PittsburghPA15260 United States Herzberg Institute of Astrophysics National Research Council of Canada PentictonBCV2A 6J9 Canada Department of Physics and Astronomy Macquarie University NSW2109 Australia Macquarie University Research Centre for Astronomy Astrophysics & Astrophotonics SydneyNSW2109 Australia Columbia Astrophysics Laboratory Columbia University New YorkNY United States Sternberg Astronomical Institute Moscow State University Universitetskii pr. 13 Moscow119992 Russia Western Sydney University Locked Bag 1797 Penrith South DCNSW2751 Australia Department of Computational Math Science and Engineering Michigan State University East LansingMI48824 United States The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova StockholmSE-106 91 Sweden Center for Computational Astrophysics Flatiron Institute 162 W. 5th Avenue New YorkNY10011 United States Department of Astronomy University of Cape Town Private Bag X3 Rondebosch7701 South Africa Instituto de Telecomunicações Campus Universitário de Santiago Aveiro3810-193 Portugal Department of Physics Indian Institute of Science Bangalore560012 India Federated IT 1201 Wilson Blvd 27th Floor ArlingtonVA22209 United States

We present radio observations (1–40 GHz) for 36 classical novae, representing data from over five decades compiled from the literature, telescope archives, and our own programs. Our targets display a striking diversity in their optical parameters (e.g., spanning optical fading timescales, t2 = 1–263 days), and we find a similar diversity in the radio light curves. Using a brightness temperature analysis, we find that radio emission from novae is a mixture of thermal and synchrotron emission, with non-thermal emission observed at earlier times. We identify high brightness temperature emission (TB > 5 × 104 K) as an indication of synchrotron emission in at least 9 (25%) of the novae. We find a class of synchrotron-dominated novae with mildly evolved companions, exemplified by V5589 Sgr and V392 Per, that appear to be a bridge between classical novae with dwarf companions and symbiotic binaries with giant companions. Four of the novae in our sample have two distinct radio maxima (the first dominated by synchrotron and the later by thermal emission), and in four cases the early synchrotron peak is temporally coincident with a dramatic dip in the optical light curve, hinting at a common site for particle acceleration and dust formation. We publish the light curves as tables and encourage use of these data by the broader community in multi-wavelength studies and modeling efforts. © 2021, CC BY.

关键词： Radio astronomy

Highly ionized clumps shooting out from a quasar at relativistic speeds

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arXiv 2025年

作者： Audard, Marc Awaki, Hisamitsu Ballhausen, Ralf Bamba, Aya Behar, Ehud Boissay-Malaquin, Rozenn Brenneman, Laura Brown, Gregory V. Corrales, Lia Costantini, Elisa Cumbee, Renata Trigo, María Díaz Done, Chris Dotani, Tadayasu Ebisawa, Ken Eckart, Megan Eckert, Dominique Enoto, Teruaki Eguchi, Satoshi Ezoe, Yuichiro Foster, Adam Fujimoto, Ryuichi Fujita, Yutaka Fukazawa, Yasushi Fukushima, Kotaro Furuzawa, Akihiro Gallo, Luigi García, Javier A. Gu, Liyi Guainazzi, Matteo Hagino, Kouichi Hamaguchi, Kenji Hatsukade, Isamu Hayashi, Katsuhiro Hayashi, Takayuki Hell, Natalie Hodges-Kluck, Edmund Hornschemeier, Ann Ichinohe, Yuto Ishida, Manabu Ishikawa, Kumi Ishisaki, Yoshitaka Kaastra, Jelle Kallman, Timothy Kara, Erin Katsuda, Satoru Kanemaru, Yoshiaki Kelley, Richard Kilbourne, Caroline Kitamoto, Shunji Kobayashi, Shogo Kohmura, Takayoshi Kubota, Aya Leutenegger, Maurice Loewenstein, Michael Maeda, Yoshitomo Markevitch, Maxim Matsumoto, Hironori Matsushita, Kyoko McCammon, Dan McNamara, Brian Mernier, François Miller, Eric D. Miller, Jon M. Mitsuishi, Ikuyuki Mizumoto, Misaki Mizuno, Tsunefumi Mori, Koji Mukai, Koji Murakami, Hiroshi Mushotzky, Richard Nakajima, Hiroshi Nakazawa, Kazuhiro Ness, Jan-Uwe Nobukawa, Kumiko Nobukawa, Masayoshi Noda, Hirofumi Odaka, Hirokazu Ogawa, Shoji Ogorzalek, Anna Okajima, Takashi Ota, Naomi Paltani, Stephane Petre, Robert Plucinsky, Paul Porter, Frederick Scott Pottschmidt, Katja Sato, Kosuke Sato, Toshiki Sawada, Makoto Seta, Hiromi Shidatsu, Megumi Simionescu, Aurora Smith, Randall Suzuki, Hiromasa Szymkowiak, Andrew Takahashi, Hiromitsu Takeo, Mai Tamagawa, Toru Tamura, Keisuke Tanaka, Takaaki Tanimoto, Atsushi Tashiro, Makoto Terada, Yukikatsu Terashima, Yuichi Tsuboi, Yohko Tsujimoto, Masahiro Tsunemi, Hiroshi Tsuru, Takeshi G. Uchida, Hiroyuki Uchida, Nagomi Uchida, Yuusuke Uchiyama, Hideki Ueda, Yoshihiro Uno, Shinichiro Vink, Jacco Watanabe, Shin Williams, Brian J. Yamada, Satoshi Yamada, Shinya Yamaguchi, Hiroya Yamaoka, Kazutaka Yamasaki, Noriko Yamauchi, Makoto Yamauchi, S Department of Astronomy University of Geneva VersoixCH-1290 Switzerland Department of Physics Ehime University Ehime790-8577 Japan Department of Astronomy University of Maryland College ParkMD20742 United States NASA / Goddard Space Flight Center GreenbeltMD20771 United States Center for Research and Exploration in Space Science and Technology NASA / GSFC CRESST II GreenbeltMD20771 United States Department of Physics University of Tokyo Tokyo113-0033 Japan Department of Physics Technion Technion City Haifa3200003 Israel BaltimoreMD21250 United States Center for Astrophysics — Harvard-Smithsonian MA02138 United States Lawrence Livermore National Laboratory CA94550 United States Department of Astronomy University of Michigan MI48109 United States SRON Netherlands Institute for Space Research Leiden Netherlands ESO Karl-Schwarzschild-Strasse 2 Garching bei München85748 Germany Centre for Extragalactic Astronomy Department of Physics University of Durham South Road DurhamDH1 3LE United Kingdom Kanagawa252-5210 Japan Department of Physics Kyoto University Kyoto606-8502 Japan Department of Economics Kumamoto Gakuen University Kumamoto862-8680 Japan Department of Physics Tokyo Metropolitan University Tokyo192-0397 Japan Department of Physics Hiroshima University Hiroshima739-8526 Japan Department of Physics Fujita Health University Aichi470-1192 Japan Department of Astronomy and Physics Saint Mary’s University NSB3H 3C3 Canada Cahill Center for Astronomy and Astrophysics California Institute of Technology PasadenaCA91125 United States Noordwijk2200 AG Netherlands Faculty of Engineering University of Miyazaki Miyazaki889-2192 Japan RIKEN Nishina Center Saitama351-0198 Japan Leiden Observatory University of Leiden P.O. Box 9513 LeidenNL-2300 RA Netherlands Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology MA02139 United States Department of Physics Saitama University Sai

Evidence indicates that supermassive black holes exist at the centers of virtually all galaxies. Their mass correlates with the galactic bulge mass1, suggesting a co-evolution with their host galaxies2, most likely through powerful outflows/winds3. X-ray observations have revealed the presence of highly ionized winds outflowing at sub-relativistic speeds from the accretion disks around supermassive black holes4,5. However, the limited spectral resolution of current X-ray instruments has left the physical structure of the winds poorly understood, as well as their location, both of which are essential for estimating the wind kinetic power6,7. Here, the first XRISM observation of the luminous quasar, PDS 456, is reported. The high-resolution spectrometer Resolve onboard XRISM enabled the discovery of five discrete velocity components outflowing at 20–30% of the speed of light. This demonstrates that the wind structure is highly inhomogeneous, which is inferred to consist of up to a million clumps of size (0.2–1.2) × 1015 cm located (2–4) × 1016 cm away from the X-ray source. The mass outflow rate is estimated to be 60–170 solar masses per year. Subsequently, the wind kinetic power is more than 1047 erg s−1, exceeding the Eddington luminosity limit. This is more than enough to significantly impact the galaxy. Copyright © 2025, The Authors. All rights reserved.

关键词： X ray detectors