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arXiv 2024年

作者： Chen, Michael Chun-Yuan Fissel, Laura M. Sadavoy, Sarah I. Rosolowsky, Erik Doi, Yasuo Arzoumanian, Doris Bastien, Pierre Coudé, Simon Di Francesco, James Friesen, Rachel Furuya, Ray S. Hwang, Jihye Inutsuka, Shu-Ichiro Johnstone, Doug Karoly, Janik Kwon, Jungmi Kwon, Woojin Le Gouellec, Valentin J.M. Liu, Hong-Li Mairs, Steve Onaka, Takashi Pattle, Kate Rawlings, Mark G. Tahani, Mehrnoosh Tamura, Motohide Wang, Jia-Wei Department of Physics Engineering Physics and Astronomy Queen’s University KingstonONK7L 3N6 Canada Department of Physics University of Alberta EdmontonABT6G 2E1 Canada Department of Earth Science and Astronomy The University of Tokyo 3-8-1 Komaba Meguro Tokyo153-8902 Japan National Astronomical Observatory of Japan Osawa 2-21-1 Mitaka Tokyo181-8588 Japan Université de Montréal Département de Physique 1375 Avenue Thérèse-Lavoie-Roux MontréalQCH2V 0B3 Canada Department of Earth Environment and Physics Worcester State University WorcesterMA01602 United States Center for Astrophysics | Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States NRC Herzberg Astronomy and Astrophysics 5071 West Saanich Rd VictoriaBCV9E 2E7 Canada Department of Physics and Astronomy University of Victoria VictoriaBCV8P 5C2 Canada David A. Dunlap Department of Astronomy and Astrophysics University of Toronto 50 St. George Street TorontoONM5S 3H4 Canada Institute of Liberal Arts and Sciences Tokushima University Minami Jousanajima-machi 1-1 Tokushima770-8502 Japan Korea Astronomy and Space Science Institute 776 Daedeokdae-ro Yuseong-gu Daejeon34055 Korea Republic of University of Science and Technology Korea 217 Gajeong-ro Yuseong-gu Daejeon34113 Korea Republic of Department of Physics Graduate School of Science Nagoya University Furo-cho Chikusa-ku Nagoya464-8602 Japan Jeremiah Horrocks Institute University of Central Lancashire PrestonPR1 2HE United Kingdom Department of Astronomy Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-0033 Japan Department of Earth Science Education Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of SNU Astronomy Research Center Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of NASA Ames Research Center Space Science and Astrobiology Division M.S. 245-6 Moffett FieldCA94035 United States NASA Postdoc

Magnetic fields play an important role in shaping and regulating star formation in molecular clouds. Here, we present one of the first studies examining the relative orientations between magnetic (B) fields and the dust emission, gas column density, and velocity centroid gradients on the 0.02 pc (core) scales, using the BISTRO and VLA+GBT observations of the NGC 1333 star-forming clump. We quantified these relative orientations using the Project Rayleigh Statistic (PRS) and found preferential global parallel alignment between the B field and dust emission gradients, consistent with large-scale studies with Planck. No preferential global alignments, however, are found between the B field and velocity gradients. Local PRS calculated for subregions defined by either dust emission or velocity coherence further revealed that the Bfield does not preferentially align with dust emission gradients in most emission-defined subregions, except in the warmest ones. The velocity-coherent structures, on the other hand, also showed no preferred B field alignments with velocity gradients, except for one potentially bubble-compressed region. Interestingly, the velocity gradient magnitude in NGC 1333 ubiquitously features prominent ripple-like structures that are indicative of magnetohydrodynamic (MHD) waves. Finally, we found B field alignments with the emission gradients to correlate with dust temperature and anticorrelate with column density, velocity dispersion, and velocity gradient magnitude. The latter two anticorrelations suggest that alignments between gas structures and B fields can be perturbed by physical processes that elevate velocity dispersion and velocity gradients, such as infall, accretions, and MHD waves. © 2024, CC BY.

关键词： Plasma magnetohydrodynamic waves

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TOI-2458 b: A mini-Neptune consistent with in situ hot Jupiter formation

arXiv

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arXiv 2024年

作者： Šubjak, Jan Gandolfi, Davide Goffo, Elisa Rapetti, David Jankowski, Dawid Mizuki, Toshiyuki Dai, Fei Serrano, Luisa M. Wilson, Thomas G. Goździewski, Krzysztof Nowak, Grzegorz Jenkins, Jon M. Twicken, Joseph D. Winn, Joshua N. Bieryla, Allyson Ciardi, David R. Cochran, William D. Collins, Karen A. Deeg, Hans J. Garcia, Rafael A. Guenther, Eike W. Hatzes, Artie P. Kabath, Petr Korth, Judith Latham, David W. Livingston, John H. Lund, Michael B. Mathur, Savita Narita, Norio Orell-Miquel, Jaume Palle, Enric Persson, Carina M. Redfield, Seth Schwarz, Richard P. Watanabe, David Ziegler, Carl Astronomical Institute Czech Academy of Sciences Fričova 298 Ondřejov251 65 Czech Republic Center for Astrophysics | Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Dipartimento di Fisica Universita degli Studi di Torino via Pietro Giuria 1 TorinoI-10125 Italy Thuringer Landessternwarte Tautenburg Sternwarte 5 Tautenburg07778 Germany NASA Ames Research Center Moffett FieldCA94035 United States Research Institute for Advanced Computer Science Universities Space Research Association WashingtonDC20024 United States Institute of Astronomy Faculty of Physics Astronomy and Informatics Nicolaus Copernicus University Grudziadzka 5 Toruń87-100 Poland Astrobiology Center of NINS 2-21-1 Osawa Mitaka Tokyo181-8588 Japan National Astronomical Observatory of Japan 2-21-2 Osawa Mitaka Tokyo181-8588 Japan Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Department of Physics University of Warwick Gibbet Hill Road CoventryCV4 7AL United Kingdom SETI Institute Mountain ViewCA94043 United States Department of Astrophysical Sciences Princeton University PrincetonNJ08544 United States NASA Exoplanet Science Institute-Caltech/IPAC PasadenaCA91125 United States McDonald Observatory The University of Texas AustinTX United States Center for Planetary Systems Habitability The University of Texas AustinTX United States C. Via Lactea S/N Tenerife La LagunaE-38205 Spain Dept. de Astrofisica Tenerife La LagunaE-38206 Spain Universite Paris-Saclay Universite Paris Cite CEA CNRS AIM Gif-sur-Yvette91191 France Lund Observatory Division of Astrophysics Department of Physics Lund University Box 118 Lund22100 Sweden Astronomical Science Program Graduate University for Advanced Studies SOKENDAI 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Komaba Institute for Science The University of Tokyo 3-8-1 Komaba Meguro Tokyo153-8902 Japan Chalmers University of Technology Departmen

We report on the discovery and spectroscopic confirmation of TOI-2458 b, a transiting mini-Neptune around an F-type star leaving the mainsequence with a mass of M*= 1.05 ± 0.03Mo, a radius of R*= 1.31 ± 0.03 Ro, an effective temperature of Teff = 6005 ± 50 K, and a metallicity of -0.10 ± 0.05 dex. By combining TESS photometry with high-resolution spectra acquired with the HARPS spectrograph, we found that the transiting planet has an orbital period of ∼3.74 days, a mass of Mp = 13.31±0.99M⊕ and a radius of Rp = 2.83±0.20 R⊕. The host star TOI-2458 shows a short activity cycle of ∼54 days revealed in the HARPS S-index and Hα times series. We took the opportunity to investigate other F stars showing activity cycle periods comparable to that of TOI-2458 and found that they have shorter rotation periods than would be expected based on the gyrochronology predictions. In addition, we determined TOI-2458's stellar inclination angle to be i*= 10.6+13.3 -10.6 degrees. We discuss that both phenomena (fast stellar rotation and planet orbit inclination) could be explained by in situ formation of a hot Jupiter interior to TOI-2458 b. It is plausible that this hot Jupiter was recently engulfed by the star. Analysis of HARPS spectra has identified the presence of another planet with a period of P = 16.55 ± 0.06 days and a minimum mass of Mp sin i = 10.22 ± 1.90M⊕. Using dynamical stability analysis, we constrained the mass of this planet to the range Mc (10, 25)M⊕. © 2024, CC BY.

关键词： Stars

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A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b

arXiv

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arXiv 2023年

作者： Coulombe, Louis-Philippe Benneke, Björn Challener, Ryan Piette, Anjali A.A. Wiser, Lindsey S. Mansfield, Megan MacDonald, Ryan J. Beltz, Hayley Feinstein, Adina D. Radica, Michael Savel, Arjun B. Dos Santos, Leonardo A. Bean, Jacob L. Parmentier, Vivien Wong, Ian Rauscher, Emily Komacek, Thaddeus D. Kempton, Eliza M.-R. Tan, Xianyu Hammond, Mark Lewis, Neil T. Line, Michael R. Lee, Elspeth K.H. Shivkumar, Hinna Crossfield, Ian J.M. Nixon, Matthew C. Rackham, Benjamin V. Wakeford, Hannah R. Welbanks, Luis Zhang, Xi Batalha, Natalie M. Berta-Thompson, Zachory K. Changeat, Quentin Désert, Jean-Michel Espinoza, Néstor Goyal, Jayesh M. Harrington, Joseph Knutson, Heather A. Kreidberg, Laura López-Morales, Mercedes Shporer, Avi Sing, David K. Stevenson, Kevin B. Aggarwal, Keshav Ahrer, Eva-Maria Alam, Munazza K. Bell, Taylor J. Blecic, Jasmina Caceres, Claudio Carter, Aarynn L. Casewell, Sarah L. Crouzet, Nicolas Cubillos, Patricio E. Decin, Leen Fortney, Jonathan J. Gibson, Neale P. Heng, Kevin Henning, Thomas Iro, Nicolas Kendrew, Sarah Lagage, Pierre-Olivier Leconte, Jérémy Lendl, Monika Lothringer, Joshua D. Mancini, Luigi Mikal-Evans, Thomas Molaverdikhani, Karan Nikolov, Nikolay K. Ohno, Kazumasa Palle, Enric Piaulet, Caroline Redfield, Seth Roy, Pierre-Alexis Tsai, Shang-Min Venot, Olivia Wheatley, Peter J. Department of Physics Trottier Institute for Research on Exoplanets Université de Montréal MontréalQC Canada Department of Astronomy University of Michigan Ann ArborMI United States Earth and Planets Laboratory Carnegie Institution for Science WashingtonDC United States School of Earth and Space Exploration Arizona State University TempeAZ United States Steward Observatory University of Arizona TucsonAZ United States NHFP Sagan Fellow United States Department of Astronomy Carl Sagan Institute Cornell University NY United States Department of Astronomy and Astrophysics University of Chicago ChicagoIL United States NSF Graduate Research Fellow United States Department of Astronomy University of Maryland College ParkMD United States Center for Computational Astrophysics Flatiron Institute New YorkNY United States Space Telescope Science Institute BaltimoreMD United States Université Côte d’Azur Observatoire de la Côte d’Azur CNRS Laboratoire Lagrange France NASA Goddard Space Flight Center GreenbeltMD United States NASA Postdoctoral Program Fellow United States Tsung-Dao Lee Institute Shanghai Jiao Tong University Shanghai China School of Physics and Astronomy Shanghai Jiao Tong University Shanghai China Atmospheric Oceanic and Planetary Physics Department of Physics University of Oxford Oxford United Kingdom Department of Mathematics and Statistics Faculty of Environment Science and Economy University of Exeter Exeter United Kingdom Center for Space and Habitability University of Bern Bern Switzerland Anton Pannekoek Institute for Astronomy University of Amsterdam Amsterdam Netherlands Department of Physics & Astronomy University of Kansas LawrenceKS United States Department of Earth Atmospheric and Planetary Sciences Massachusetts Institute of Technology CambridgeMA United States Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA United States 51 Pegasi b Fellow France School of

Close-in giant exoplanets with temperatures greater than 2,000 K ("ultra-hot Jupiters") have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble and Spitzer space Telescopes1;2;3. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis3;4;5;6;7;8;9;10;11;12. Here we present a dayside thermal emission spectrum of the ultrahot Jupiter WASP-18b obtained with the NIRISS13 instrument on JWST. The data span 0.85 to 2.85 µm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6σ confidence) and evidence for optical opacity, possibly due to H−, TiO, and VO (combined significance of 3.8σ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy element abundance ("metallicity", M/H = 1.03+1.11−0.51 × solar), and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the sub-stellar point that decreases steeply and symmetrically with longitude toward the terminators. © 2023, CC BY.

关键词： Molecular oxygen

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Accuracy assessment of several classification algorithms with and without hue saturation intensity input features on object analyses on benthic habitat mapping in the Pajenekang Island Waters, South Sulawesi

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IOP Conference Series: Earth and Environmental science 2020年第1期429卷

作者： T Pragunanti B Nababan H Madduppa D Kushardono Marine Technology Study Program Graduate School IPB University Bogor Department of Marine Technology Faculty of Fisheries and Marine Science IPB University Bogor Remote Sensing Center National Aeronautics and Space Agency Jakarta

Object-based image analysis (OBIA) method has been proven to improve the accuracy value on benthic habitat mapping. The purpose of this study was to assess the accuracy of several classification algorithms on benthic habitat mapping based on OBIA method with and without input feature of Hue Saturation Intensity (HSI) in the Pajenekang island waters, South Sulawesi, Indonesia. Sentinel-2A satellite imagery with 10 m2 spatial resolution acquired on 3 September 2018 was used in this study. During OBIA analyses, we segmented the object into 5, 10, and 15 classes and treated each of them with input features of mean+ratio vs mean+ratio+hue saturation intensity (HSI). We later classified the benthic habitat by applying several classification algorithms such as the Bayes, K-Nearest Neighbour (KNN), Support Vector Machine (SVM), and Decision Tree (DT). The results showed that the Bayes algorithm produced highest accuracy of 78.35% within 10 segmentation classes and input features of mean+ratio+HSI followed by the KNN of 71.13% with 5 segmentation classes and input features of mean+ration+HSI. The addition of HSI input features into OBIA analyses increased the accuracy of benthic habitat classification mapping of 4.13% with the Bayes classification algorithm.

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Three short-period Earth-sized planets around M dwarfs discovered by TESS: TOI-5720 b, TOI-6008 b, and TOI-6086 b

arXiv

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arXiv 2024年

作者： Barkaoui, K. Schwarz, R.P. Narita, N. Mistry, P. Magliano, C. Hirano, T. Maity, M. Burgasser, A.J. Rackham, B.V. Murgas, F. Pozuelos, F.J. Stassun, K.G. Everett, M.E. Ciardi, D.R. Lamman, C. Pass, E.K. Bieryla, A. Aganze, C. Esparza-Borges, E. Collins, K.A. Covone, G. de Leon, J. Dévora-Pajares, M. de Wit, J. Fukuda, Izuru Fukui, A. Gerasimov, R. Gillon, M. Hayashi, Y. Howell, S.B. Ikoma, M. Ikuta, K. Jenkins, J.M. Karpoor, P.R. Kawai, Y. Kimura, T. Kotani, T. Latham, D.W. Mori, M. Pallé, E. Parviainen, H. Patel, Y.G. Ricker, G. Relles, H.M. Shporer, A. Seager, S. Softich, E. Srdoc, G. Tamura, M. Theissen, C.A. Twicken, J.D. Vanderspek, R. Watanabe, N. Watkins, C.N. Winn, J.N. Wohler, B. Astrobiology Research Unit Université de Liège Allée du 6 Août 19C LiègeB-4000 Belgium Department of Earth Atmospheric and Planetary Science Massachusetts Institute of Technology 77 Massachusetts Avenue CambridgeMA02139 United States Calle Vía Láctea s/n Tenerife La Laguna38200 Spain Center for Astrophysics Harvard & Smithsonian 60 Garden St CambridgeMA02138 United States Komaba Institute for Science The University of Tokyo 3-8-1 Komaba Meguro Tokyo153-8902 Japan Astrobiology Center 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Department of Physics Sardar Vallabhbhai National Institute of Technology Gujarat Surat395007 India Dipartimento di Fisica "Ettore Pancini" Università di Napoli Federico II Napoli Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo Via Cintia Edificio 6 Napoli80126 Italy INAF - Osservatorio Astronomico di Capodimonte via Moiariello 16 Napoli80131 Italy National Astronomical Observatory 2-21-1 Osawa Mitaka-shi Tokyo181-8588 Japan Department of Physics Presidency University West Bengal Kolkata700073 India Department of Astronomy & Astrophysics University of California San Diego La Jolla CA92093 United States Department of Physics Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Tenerife La LagunaE-38206 Spain Glorieta de la Astronomía s/n Granada18008 Spain Department of Physics and Astronomy Vanderbilt University NashvilleTN37235 United States NSF’s National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Ave. TucsonAZ85719 United States NASA Exoplanet Science Institute-Caltech/IPAC PasadenaCA91125 United States Department of Physics Center for Astrophysics & Space Sciences University of California San Diego La Jolla CA92093 United States Department of Physics & Astronomy Stanford University StanfordCA94305 United States Department of Multi-Disciplinary Sciences Graduate School of Arts

One of the main goals of the NASA Transiting Exoplanet Survey Satellite (TESS) mission is the discovery of Earth-like planets around nearby M-dwarf stars. We present the discovery and validation of three new short-period Earth-sized planets orbiting nearby M dwarfs: TOI-5720 b, TOI-6008 b, and TOI-6086 b. We combined TESS data, ground-based multicolor light curves, ground-based optical and near-infrared spectroscopy, and Subaru/IRD radial velocity data to validate the planetary candidates and constrain the physical parameters of the systems. In addition, we used archival images, high-resolution imaging, and statistical validation techniques to support the planetary validation. TOI-5720 b is an Earth-sized planet with a radius of Rp = 1.09 ± 0.07 R☉. It orbits a nearby (36 pc) M2.5 host with an orbital period of P = 1.4344555 ± 0.0000036 days. It has an equilibrium temperature of Teq = 708 ± 19 K (assuming a null albedo) and an incident flux of S p = 41.7 ± 4.5 S☉. TOI-6008 b is a short-period planet of P = 0.8574347 ± 0.0000424 day. It has a radius of Rp = 1.03 ± 0.05 R☉, an equilibrium temperature of Teq = 707 ± 19 K, and an incident flux of S p = 41.5 ± 4.5 S☉. The host star (TOI-6008) is a nearby (23 pc) M5 with an effective temperature of Teff = 3075 ± 75 K. Based on the radial velocity measurements collected with Subaru/IRD, we set a 3σ upper limit of Mp ☉, thus ruling out a star or brown dwarf as the transiting companion. TOI-6086 b orbits its nearby (32 pc) M3 host star (Teff = 3200 ± 75 K) every 1.3888725 ± 0.0000827 days and has a radius of Rp = 1.18 ± 0.07 R☉, an equilibrium temperature of Teq = 634 ± 16 K, and an incident flux of S p = 26.8 ± 2.7 S☉. Additional high-precision radial velocity measurements are needed to derive the planetary masses and bulk densities and to search for additional planets in the systems. Moreover, short-period Earth-sized planets orbiting around nearby M dwarfs are suitable targets for an atmospheric characterization with the

关键词： Stars

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SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES). V. Confusion-limited Submillimeter Galaxy Number Counts at 450 µm and Data Release for the COSMOS Field

arXiv

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arXiv 2024年

作者： Gao, Zhen-Kai Lim, Chen-Fatt Wang, Wei-Hao Chen, Chian-Chou Smail, Ian Chapman, Scott C. Zheng, Xian Zhong Shim, Hyunjin Kodama, Tadayuki Ao, Yiping Chang, Siou-Yu Clements, David L. Dunlop, James S. Ho, Luis C. Hsu, Yun-Hsin Hwang, Chorng-Yuan Hwang, Ho Seong Koprowski, M.P. Scott, Douglas Serjeant, Stephen Toba, Yoshiki Urquhart, Sheona A. No. 1 Section 4 Roosevelt Rd. Taipei10617 Taiwan Graduate Institute of Astronomy National Central University 300 Zhongda Road Zhongli Taoyuan32001 Taiwan Centre for Extragalactic Astronomy Department of Physics Durham University South Road DurhamDH1 3LE United Kingdom Department of Physics and Atmospheric Science Dalhousie University Halifax HalifaxNSB3H 3J5 Canada Purple Mountain Observatory Key Laboratory for Radio Astronomy Chinese Academy of Sciences 10 Yuanhua Road Nanjing210023 China School of Astronomy and Space Science University of Science and Technology of China Anhui Hefei230026 China Department of Earth Science Education Kyungpook National University 80 Daehak-ro Buk-gu Daegu41566 Korea Republic of Astronomical Institute Tohoku University 6-3 Aramaki Aoba Miyagi Sendai980-8578 Japan Institute of Astronomy Department of Physics National Tsing Hua University Hsinchu30013 Taiwan Imperial College London Blackett Laboratory Prince Consort Road LondonSW7 2AZ United Kingdom SUPA Institute for Astronomy University of Edinburgh Royal Observatory EdinburghEH9 3HJ United Kingdom Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China Department of Astronomy School of Physics Peking University Beijing100871 China Department of Philosophy National Taiwan University No. 1 Section 4 Roosevelt Rd. Taipei10617 Taiwan Astronomy Program Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of SNU Astronomy Research Center Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of Institute of Astronomy Faculty of Physics Astronomy and Informatics Nicolaus Copernicus University Grudziadzka 5 Torun87-100 Poland Department of Physics and Astronomy University of British Columbia 6224 Agricultural Road VancouverBCV6T 1Z1 Canada School of Physical Sciences The Open University Milton KeynesMK7 6AA United Kingdom

We present confusion-limited SCUBA-2 450-µm observations in the COSMOS-CANDELS region as part of the JCMT Large program, SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES). Our maps at 450 and 850 µm cover an area of 450 arcmin2. We achieved instrumental noise levels of σ450 = 0.59 mJy beam−1 and σ850 = 0.09 mJy beam−1 in the deepest area of each map. The corresponding confusion noise levels are estimated to be 0.65 and 0.36 mJy beam−1. Above the 4 (3.5) σ threshold, we detected 360 (479) sources at 450 µm and 237 (314) sources at 850 µm. We derive the deepest blank-field number counts at 450 µm, covering the flux-density range of 2 to 43 mJy. These are in agreement with other SCUBA-2 blank-field and lensing-cluster observations, but are lower than various model counts. We compare the counts with those in other fields and find that the field-to-field variance observed at 450 µm at the R = 6′ scale is consistent with Poisson noise, so there is no evidence of strong 2-D clustering at this scale. Additionally, we derive the integrated surface brightness at 450 µm down to 2.1 mJy to be (Equation presented) Jy deg−2, contributing to (41±4)% of the 450-µm extragalactic background light (EBL) measured by COBE and Planck. Our results suggest that the 450-µm EBL may be fully resolved at (Equation presented) mJy, which extremely deep lensing-cluster observations and next-generation submillimeter instruments with large aperture sizes may be able to achieve. © 2024, CC BY.

关键词： Galaxies

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The Black Hole Explorer: Motivation and Vision

arXiv

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arXiv 2024年

作者： Johnson, Michael D. Akiyama, Kazunori Baturin, Rebecca Bilyeu, Bryan Blackburn, Lindy Boroson, Don Cárdenas-Avendaño, Alejandro Chael, Andrew Chan, Chi-Kwan Chang, Dominic Cheimets, Peter Chou, Cathy Doeleman, Sheperd S. Farah, Joseph Galison, Peter Gamble, Ronald Gammie, Charles F. Gelles, Zachary Gómez, José L. Gralla, Samuel E. Grimes, Paul Gurvits, Leonid I. Hadar, Shahar Haworth, Kari Hada, Kazuhiro Hecht, Michael H. Honma, Mareki Houston, Janice Hudson, Ben Issaoun, Sara Jia, He Jorstad, Svetlana Kauffmann, Jens Kovalev, Yuri Y. Kurczynski, Peter Lafon, Robert Lupsasca, Alexandru Lehmensiek, Robert Ma, Chung-Pei Marrone, Daniel P. Marscher, Alan P. Melnick, Gary J. Narayan, Ramesh Niinuma, Kotaro Noble, Scott C. Palmer, Eric J. Palumbo, Daniel C.M. Paritsky, Lenny Peretz, Eliad Pesce, Dominic Plavin, Alexander Quataert, Eliot Rana, Hannah Ricarte, Angelo Roelofs, Freek Shtyrkova, Katia Sinclair, Laura C. Small, Jeffrey Kumara, Sridharan Tirupati Srinivasan, Ranjani Strominger, Andrew Tiede, Paul Tong, Edward Wang, Jade Weintroub, Jonathan Wielgus, Maciek Wong, George Zhang, Xinyue Alice Center for Astrophysics | Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Black Hole Initiative Harvard University 20 Garden Street CambridgeMA02138 United States Haystack Observatory Massachusetts Institute of Technology WestfordMA01886 United States Mizusawa VLBI Observatory National Astronomical Observatory of Japan Iwate023-0861 Japan MIT Lincoln Laboratory LexingtonMA02421 United States Princeton Gravity Initiative Princeton University PrincetonNJ08544 United States Steward Observatory and Department of Astronomy University of Arizona 933 N. Cherry Ave. TucsonAZ85721 United States Data Science Institute University of Arizona 1230 N. Cherry Ave. TucsonAZ85721 United States Program in Applied Mathematics University of Arizona 617 N. Santa Rita TucsonAZ85721 United States Las Cumbres Observatory 6740 Cortona Drive GoletaCA93117-5575 United States Department of Physics University of California Santa BarbaraCA93106-9530 United States Department of History of Science Harvard University CambridgeMA02138 United States Department of Physics Harvard University CambridgeMA02138 United States NASA Goddard Space Flight Center GreenbeltMD20771 United States Departments of Astronomy and of Physics University of Illinois UrbanaIL61801 United States Instituto de Astrofísica de Andalucía CSIC Glorieta de la Astronomía s/n GranadaE-18008 Spain Department of Physics University of Arizona TucsonAZ85719 United States Joint Institute for VLBI ERIC Dwingeloo7991PD Netherlands Faculty of Aerospace Engineering Delft University of Technology Delft2629 HS Netherlands Department of Mathematics and Physics University of Haifa at Oranim Kiryat Tivon3600600 Israel Haifa Research Center for Theoretical Physics and Astrophysics University of Haifa Haifa3498838 Israel 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Department of Astronomy Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-

We present the Black Hole Explorer (BHEX), a mission that will produce the sharpest images in the history of astronomy by extending submillimeter Very-Long-Baseline Interferometry (VLBI) to space. BHEX will discover and measure the bright and narrow "photon ring" that is predicted to exist in images of black holes, produced from light that has orbited the black hole before escaping. This discovery will expose universal features of a black hole's spacetime that are distinct from the complex astrophysics of the emitting plasma, allowing the first direct measurements of a supermassive black hole's spin. In addition to studying the properties of the nearby supermassive black holes M87*and Sgr A*, BHEX will measure the properties of dozens of additional supermassive black holes, providing crucial insights into the processes that drive their creation and growth. BHEX will also connect these supermassive black holes to their relativistic jets, elucidating the power source for the brightest and most efficient engines in the universe. BHEX will address fundamental open questions in the physics and astrophysics of black holes that cannot be answered without submillimeter space VLBI. The mission is enabled by recent technological breakthroughs, including the development of ultra-high-speed downlink using laser communications, and it leverages billions of dollars of existing ground infrastructure. We present the motivation for BHEX, its science goals and associated requirements, and the pathway to launch within the next decade. © 2024, CC BY.

关键词： Photons

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Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy

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Astrophysical Journal Letters 2024年第2期967卷 L21-L21页

作者： Kuzuhara, Masayuki Fukui, Akihiko Livingston, John H. Caballero, José A. de Leon, Jerome P. Hirano, Teruyuki Kasagi, Yui Murgas, Felipe Narita, Norio Omiya, Masashi Orell-Miquel, Jaume Palle, Enric Changeat, Quentin Esparza-Borges, Emma Harakawa, Hiroki Hellier, Coel Hori, Yasunori Ikuta, Kai Ishikawa, Hiroyuki Tako Kodama, Takanori Kotani, Takayuki Kudo, Tomoyuki Morales, Juan C. Mori, Mayuko Nagel, Evangelos Parviainen, Hannu Perdelwitz, Volker Reiners, Ansgar Ribas, Ignasi Sanz-Forcada, Jorge Sato, Bun’ei Schweitzer, Andreas Tabernero, Hugo M. Takarada, Takuya Uyama, Taichi Watanabe, Noriharu Zechmeister, Mathias García, Néstor Abreu Aoki, Wako Beichman, Charles Béjar, Víctor J. S. Brandt, Timothy D. Calatayud-Borras, Yéssica Carleo, Ilaria Charbonneau, David Collins, Karen A. Currie, Thayne Doty, John P. Dreizler, Stefan Fernández-Rodríguez, Gareb Fukuda, Izuru Galán, Daniel Geraldía-González, Samuel González-Garcia, Josafat Hayashi, Yuya Hedges, Christina Henning, Thomas Hodapp, Klaus Ikoma, Masahiro Isogai, Keisuke Jacobson, Shane Janson, Markus Jenkins, Jon M. Kagetani, Taiki Kambe, Eiji Kawai, Yugo Kawauchi, Kiyoe Kokubo, Eiichiro Konishi, Mihoko Korth, Judith Krishnamurthy, Vigneshwaran Kurokawa, Takashi Kusakabe, Nobuhiko Kwon, Jungmi Laza-Ramos, Andrés Libotte, Florence Luque, Rafael Madrigal-Aguado, Alberto Matsumoto, Yuji Mawet, Dimitri McElwain, Michael W. Gallardo, Pedro Pablo Meni Morello, Giuseppe Torres, Sara Muñoz Nishikawa, Jun Nugroho, Stevanus K. Ogihara, Masahiro Peláez-Torres, Alberto Rapetti, David Sánchez-Benavente, Manuel Schlecker, Martin Seager, Sara Serabyn, Eugene Serizawa, Takuma Stangret, Monika Takahashi, Aoi Teng, Huan-Yu Tamura, Motohide Terada, Yuka Ueda, Akitoshi Usuda, Tomonori Vanderspek, Roland Vievard, Sébastien Watanabe, David Winn, Joshua N. Zapatero Osorio, Maria Rosa Astrobiology Center NINS 2-21-1 Osawa Mitaka Tokyo 181-8588 Japan National Astronomical Observatory of Japan NINS 2-21-1 Osawa Mitaka Tokyo 181-8588 Japan Komaba Institute for Science The University of Tokyo 3-8-1 Komaba Meguro Tokyo 153-8902 Japan Instituto de Astrofísica de Canarias (IAC) La Laguna Tenerife E-38200 Spain Astronomical Science Program Graduate University for Advanced Studies (SOKENDAI) 2-21-1 Osawa Mitaka Tokyo 181-8588 Japan Centro de Astrobiología CSIC-INTA Camino Bajo del Castillo s/n Villanueva de la Cañada Madrid E-28692 Spain Department of Multi-Disciplinary Sciences Graduate School of Arts and Sciences The University of Tokyo 3-8-1 Komaba Meguro Tokyo 153-8902 Japan Departamento de Astrofísica Universidad de La Laguna (ULL) La Laguna Tenerife E-38206 Spain European Space Agency (ESA) ESA Office Space Telescope Science Institute (STScI) Baltimore 21218 MD United States Department of Physics and Astronomy University College London Gower Street London WC1E 6BT United Kingdom National Astronomical Observatory of Japan 650 North A‘ohōkū Place Hilo 96720 HI United States Astrophysics Group Keele University Staffordshire ST5 5BG United Kingdom Department of Physics and Astronomy The University of Western Ontario 1151 Richmond Street London N6A 3K7 ON Canada Earth-Life Science Institute (ELSI) Tokyo Institute of Technology 2-12-1-I7E-315 Ookayama Meguro-ku Tokyo 152-8550 Japan Institut de Ciències de l’Espai (ICE CSIC) Campus UAB Can Magrans s/n Bellaterra Barcelona 08193 Spain Institut d’Estudis Espacials de Catalunya (IEEC) c/ Gran Capità 2-4 Barcelona 08034 Spain Institut für Astrophysik und Geophysik Georg-August-Universität Friedrich-Hund-Platz 1 Göttingen 37077 Germany Department of Physics Ariel University Ariel 40700 Israel Department of Earth and Planetary Sciences School of Science Tokyo Institute of Technology 2-12-1 Ookayama Meguro-ku Tokyo 152-8551 Japan Hamburger Sternwarte Goje

Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period (P _orb) of 12.76 days. The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous P _orb from TESS data. We confirmed the transit signal and P _orb using ground-based photometry with MuSCAT2 and MuSCAT3, and validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host star is inactive, with an X-ray-to-bolometric luminosity ratio of log L X / L bol ≈ − 5.7 . Joint analysis of the light curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 ± 0.05 R _⊕, a 3σ mass upper limit of 3.9 M _⊕, and an equilibrium temperature of 315 ± 6 K assuming zero albedo. The transmission spectroscopy metric (TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST. © 2024. The Author(s). Published by the American Astronomical Society.

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MAGIC observation of BL Lacertae flaring period in 2020 38

MAGIC observation of BL Lacertae flaring period in 2020

引用

38th International Cosmic Ray Conference, ICRC 2023

作者： Imazawa, R. Strišković, J. Jormanainen, J. Truzzi, S. Lindfors, E. Dominis Prester, D. Bonnoli, G. Fukazawa, Y. Suda, Y. Abe, H. Abe, S. Abhir, J. Acciari, V.A. Agudo, I. Aniello, T. Ansoldi, S. Antonelli, L.A. Arbet Engels, A. Arcaro, C. Artero, M. Asano, K. Baack, D. Babić, A. Baquero, A. Barres de Almeida, U. Barrio, J.A. Batković, I. Baxter, J. Becerra González, J. Bednarek, W. Bernardini, E. Bernardos, M. Bernete, J. Berti, A. Besenrieder, J. Bigongiari, C. Biland, A. Blanch, O. Bošnjak, Ž. Burelli, I. Busetto, G. Campoy-Ordaz, A. Carosi, A. Carosi, R. Carretero-Castrillo, M. Castro-Tirado, A.J. Ceribella, G. Chai, Y. Chilingarian, A. Cifuentes, A. Cikota, S. Colombo, E. Contreras, J.L. Cortina, J. Covino, S. D’Amico, G. D’Elia, V. Da Vela, P. Dazzi, F. De Angelis, A. De Lotto, B. Del Popolo, A. Delfino, M. Delgado, J. Delgado Mendez, C. Depaoli, D. Di Pierro, F. Di Venere, L. Dominis Prester, D. Donini, A. Dorner, D. Doro, M. Elsaesser, D. Emery, G. Escudero, J. Fariña, L. Fattorini, A. Foffano, L. Font, L. Fröse, S. Fukami, S. Fukazawa, Y. García López, R.J. Garczarczyk, M. Gasparyan, S. Gaug, M. Giesbrecht Paiva, J.G. Giglietto, N. Giordano, F. Gliwny, P. Godinović, N. Grau, R. Green, D. Green, J.G. Hadasch, D. Hahn, A. Hassan, T. Heckmann, L. Herrera, J. Hrupec, D. Hütten, M. Imazawa, R. Inada, T. Iotov, R. Ishio, K. Jiménez Martínez, I. Jormanainen, J. Kerszberg, D. Kluge, G.W. Kobayashi, Y. Kouch, P.M. Kubo, H. Kushida, J. Láinez Lezáun, M. Lamastra, A. Lelas, D. Leone, F. Lindfors, E. Linhoff, L. Lombardi, S. Longo, F. López-Coto, R. López-Moya, M. López-Oramas, A. Loporchio, S. Lorini, A. Lyard, E. Machado de Oliveira Fraga, B. Majumdar, P. Makariev, M. Maneva, G. Mang, N. Manganaro, M. Mangano, S. Mannheim, K. Mariotti, M. Martínez, M. Martínez-Chicharro, M. Mas-Aguilar, A. Mazin, D. Menchiari, S. Mender, S. Mićanović, S. Miceli, D. Miener, T. Miranda, J.M. Mirzoyan, R. Molero González, M. Molina, E. Mondal, H.A. Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Hiroshima739-8526 Japan Josip Juraj Strossmayer University of Osijek Department of Physics Osijek31500 Croatia Finnish Centre for Astronomy with ESO University of Turku TurkuFI-20014 Finland Università di Siena INFN Pisa SienaI-53100 Italy INFN Sezione di Bari Dipartimento Interateneo di Fisica dell’Università e del Politecnico di Bari BariI-70125 Italy RomeI-00136 Italy The University of Tokyo Chiba Kashiwa277-8582 Japan ETH Zürich ZürichCH-8093 Switzerland Instituto de Astrofísica de Canarias Dpto. de Astrofísica Universidad de La Laguna Tenerife La LagunaE-38200 Spain Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n Granada18008 Spain Università di Udine INFN Trieste UdineI-33100 Italy Max-Planck-Institut für Physik MünchenD-80805 Germany Università di Padova INFN PadovaI-35131 Italy Barcelona BellaterraE-08193 Spain Technische Universität Dortmund DortmundD-44221 Germany Zagreb10000 Croatia IPARCOS Institute EMFTEL Department Universidad Complutense de Madrid MadridE-28040 Spain URCA RJ Rio de Janeiro22290-180 Brazil University of Lodz Faculty of Physics and Applied Informatics Department of Astrophysics Lodz90-236 Poland Centro de Investigaciones Energéticas Medioambientales y Tecnológicas MadridE-28040 Spain Departament de Física CERES-IEEC Universitat Autònoma de Barcelona BellaterraE-08193 Spain Università di Pisa INFN Pisa PisaI-56126 Italy Universitat de Barcelona ICCUB IEEC-UB BarcelonaE-08028 Spain Armenian MAGIC Group A. Alikhanyan National Science Laboratory Yerevan0036 Armenia Department for Physics and Technology University of Bergen Norway INFN MAGIC Group INFN Sezione di Catania Dipartimento di Fisica e Astronomia University of Catania CataniaI-95123 Italy INFN MAGIC Group INFN Sezione di Torino Università degli Studi di Torino TorinoI-10125 Italy INFN MAGIC Group INF

BL Lacertae (BL Lac) is one of the low-frequency peaked BL Lac object (LBL). Since August 2020, BL Lac has shown a historically high activity in HE (high-energy, 0.1 GeV 100 GeV) gamma-ray range, BL Lac was detected in several nights during an especially bright flare simultaneous with a HE flare. In the long-term light curves, X-ray and HE gamma-ray flux overall show correlation, but sometimes only HE gamma-ray was bright. These multi-wavelength (MWL) correlations may relate to the emission mechanisms and the origin of the observed flaring activity. In this contribution we will present some of the preliminary results on the MWL campaign of BL Lac in September 2020, with a focus on the X-ray and gamma-ray activity, based on the data collected by Swift-XRT, MAGIC and Fermi-LAT telescopes. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Cosmic rays

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EMPRESS. IX. Extremely Metal-Poor Galaxies are Very Gas-Rich Dispersion-Dominated Systems: Will JWST Witness Gaseous Turbulent High-z Primordial Galaxies?

arXiv

引用

arXiv 2022年

作者： Isobe, Yuki Ouchi, Masami Nakajima, Kimihiko Ozaki, Shinobu Bouché, Nicolas F. Wise, John H. Xu, Yi Emsellem, Eric Kusakabe, Haruka Hattori, Takashi Nagao, Tohru Chiaki, Gen Fukushima, Hajime Harikane, Yuichi Hayashi, Kohei Hirai, Yutaka Kim, Ji Hoon Maseda, Michael V. Nagamine, Kentaro Shibuya, Takatoshi Sugahara, Yuma Yajima, Hidenobu Aoyama, Shohei Fujimoto, Seiji Fukushima, Keita Hatano, Shun Inoue, Akio K. Ishigaki, Tsuyoshi Kawasaki, Masahiro Kojima, Takashi Komiyama, Yutaka Koyama, Shuhei Koyama, Yusei Lee, Chien-Hsiu Matsumoto, Akinori Mawatari, Ken Moriya, Takashi J. Motohara, Kentaro Murai, Kai Nishigaki, Moka Onodera, Masato Ono, Yoshiaki Rauch, Michael Saito, Tomoki Sasaki, Rin Suzuki, Akihiro Takeuchi, Tsutomu T. Umeda, Hiroya Umemura, Masayuki Watanabe, Kuria Yabe, Kiyoto Zhang, Yechi Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwanoha Chiba Kashiwa277-8582 Japan Department of Physics Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo113-0033 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan University of Tokyo Chiba Kashiwa277-8583 Japan Univ Lyon Univ Lyon1 ENS de Lyon CNRS Centre de Recherche Astrophysique de Lyon UMR5574 Saint-Genis-LavalF-69230 France Center for Relativistic Astrophysics School of Physics Georgia Institute of Technology AtlantaGA30332 United States Department of Astronomy Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo113-0033 Japan European Southern Observatory Karl-Schwarzschild-Straße 2 Garching85748 Germany Observatoire de Genéve Université de Genéve 51 Ch. des Maillettes Versoix1290 Switzerland 650 North A'ohoku Place HiloHI96720 United States Research Center for Space and Cosmic Evolution Ehime University Bunkyo-cho 2-5 Ehime Matsuyama790-8577 Japan Center for Computational Sciences University of Tsukuba Ten-nodai 1-1-1 Tsukuba Ibaraki305-8577 Japan Department of Physics and Astronomy University College London Gower Street LondonWC1E 6BT United Kingdom National Institute of Technology Ichinoseki College Hagisho Ichinoseki021-8511 Japan Astronomical Institute Tohoku University 6-3 Aoba Aramaki Aoba-ku Miyagi Sendai980-8578 Japan Department of Physics and Astronomy University of Notre Dame 225 Nieuwland Science Hall Notre DameIN46556 United States Astronomy Program Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of SNU Astronomy Research Center Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of Department of Astronomy University of Wisconsin-Madison 475 N. Charter Street MadisonWI53706 United States Theoretical Astrophysics Department of Earth & Space S

We present kinematics of 6 local extremely metal-poor galaxies (EMPGs) with low metallicities (0.016 − 0.098 Z☉) and low stellar masses (104.7 − 107.6M☉). Taking deep medium-high resolution (R ∼ 7500) integral-field spectra with 8.2-m Subaru, we resolve the small inner velocity gradients and dispersions of the EMPGs with Hα emission. Carefully masking out sub-structures originated by inflow and/or outflow, we fit 3-dimensional disk models to the observed Hα flux, velocity, and velocity-dispersion maps. All the EMPGs show rotational velocities (vrot) of 5-23 km s−1 smaller than the velocity dispersions (σ0) of 17-31 km s−1, indicating dispersion-dominated (vrot/σ0 = 0.29−0.80 gas 0.9 − 1.0. Comparing our results with other Hα kinematics studies, we find that vrot/σ0 decreases and fgas increases with decreasing metallicity, decreasing stellar mass, and increasing specific star-formation rate. We also find that simulated high-z (z ∼ 7) forming galaxies have gas fractions and dynamics similar to the observed EMPGs. Our EMPG observations and the simulations suggest that primordial galaxies are gas-rich dispersion-dominated systems, which would be identified by the forthcoming James Webb space Telescope (JWST) observations at z ∼ 7. Copyright © 2022, The Authors. All rights reserved.

关键词： Galaxies

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