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arXiv 2025年

作者： Ahmadova, F. André, K. Armesto, N. Azuelos, G. Behnke, O. Boonekamp, M. Bonvini, M. Britzger, D. Brüning, O. Bud, T.A. Cooper-Sarkar, A.M. D’Hondt, J. D’Onofrio, M. Fischer, O. Forthomme, L. Giuli, F. Gwenlan, C. Hammou, E. Holzer, B. Khanpour, H. Klein, U. Kostka, P. Lappi, T. Mäntysaari, H. Mellado, B. Newman, P.R. Olness, F.I. Osborne, J.A. Papaphilippou, Y. Paukkunen, H. Piotrzkowski, K. Polini, A. Rojo, J. Schott, M. Schumann, S. Schwanenberger, C. Staśto, A.M. Stocchi, A. Tentori, S. Tevio, M. Wang, C. Yamazaki, Y. Max-Planck-Institut für Physik Boltzmannstr. 8 Garching85748 Germany Department of Physics Universität Zürich Winterthurerstrasse 190 ZürichCH-8057 Switzerland CERN Meyrin Switzerland Instituto Galego de Física de Altas Enerxías IGFAE Universidade de Santiago de Compostela Galicia Santiago de Compostela15782 Spain Group of Particle Physics Université de Montréal MontréalQC Canada TRIUMF VancouverBC Canada Deutsches Elektronen-Synchrotron DESY Notkestr. 85 Hamburg22607 Germany CEA/IRFU Gif-sur-Yvette France INFN Sezione di Roma Piazzale Aldo Moro 5 Roma00185 Italy Department of Physics University of Oxford Denys Wilkinson Building Keble Road OxfordOX1 3RH United Kingdom Nikhef Science Park 105 Amsterdam1098 XG Netherlands Department of Physics University of Liverpool Oxford Street LiverpoolL69 7ZE United Kingdom Department of Mathematical Sciences University of Liverpool LiverpoolL69 3BX United Kingdom AGH University Faculty of Physics and Applied Computer Science Al. Mickiewicza 30 Kraków30-055 Poland Dipartimento di Fisica Università degli Studi di Roma Tor Vergata INFN Sezione di Roma Tor Vergata Via della Ricerca Scientifica 1 Rome00133 Italy DAMTP University of Cambridge Wilberforce Road CambridgeCB3 0WA United Kingdom University of Jyväskylä Department of Physics P.O. Box 35 FI-40014 Finland Helsinki Institute of Physics University of Helsinki P.O. Box 64 FI-00014 Finland School of Physics and Astronomy University of Birmingham B15 2TT United Kingdom Department of Physics Southern Methodist University DallasTX75275 United States INFN Sezione di Bologna Via C. Berti Pichat 4/2 Bologna40127 Italy Department of Physics and Astronomy Vrije Universiteit AmsterdamNL-1081 HV Netherlands Physikalisches Institut Universität Bonn Nussallee 12 Bonn53115 Germany Institut für Theoretische Physik Universität Göttingen Friedrich-Hund-Platz 1 Göttingen37077 Germany Universität Hamburg Luruper Chaussee 149 Hamburg22761

The LHeC is the project for delivering electron-nucleon collisions at CERN using the HL-LHC beams. An Energy Recovery Linac in racetrack configuration will provide 50 GeV electrons to achieve centre-of-mass energies around 1 TeV/nucleon and instantaneous luminosities around 1034 cm−2s−1. The LHeC program elaborated in the CDR of 2021 included a phase with concurrent operation of electron-hadron and hadron-hadron collisions, followed by a standalone phase of electron-hadron collisions only. In view of the current HL-LHC schedule, in this paper we have examined the possibilities of a program after the regular HL-LHC program with only electron-proton operation. In this operation mode, the LHeC would serve as an impactful bridge project between major colliders at CERN. The standalone physics program comprises electroweak, Higgs, top-quark, BSM and strong-interaction physics. In addition, it empowers the physics analyses at the HL-LHC by retrofitting measurements and searches with significantly more precise knowledge of the proton structure and αs. The accelerator technology deployed in the Energy Recovery Linac for the LHeC is a major stepping-stone for the performance, cost reduction and training for future colliders. The capital investments in the LHeC electron accelerator can be reused in a cost-efficient way as the injector for the FCC-ee. Finally, data from the LHeC are essential to enable the physics potential of any new high-energy hadron collider. The operational plan of 6 years easily fits in the period between two major colliders at CERN. Similar to the LHeC empowering the HL-LHC physics program, the FCC-eh would be an impactful addition to the FCC physics program. © 2025, CC BY.

关键词： Hadrons

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Two-dimensional perovskites with maximum symmetry enable exciton diffusion length exceeding 2 micrometers

arXiv

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arXiv 2025年

作者： Hou, Jin Fletcher, Jared Hall, Siedah J. Zhang, Hao Zacharias, Marios Volonakis, George Welton, Claire Mandani, Faiz Metcalf, Isaac Sun, Shuo Zhang, Bo Guo, Yinsheng Reddy, G.N. Manjunatha Katan, Claudine Even, Jacky Sfeir, Matthew Y. Kanatzidis, Mercouri G. Mohite, Aditya D. Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States Department of Chemistry Department of Materials Science and Engineering Northwestern University EvanstonIL60208 United States Photonics Initiative Advanced Science Research Center City University of New York New York10031 United States Department of Physics The Graduate Center City University of New York New York10016 United States Department of Chemical and Biomolecular Engineering Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley‐Curl Institute Rice University HoustonTX77005 United States Univ Rennes INSA Rennes CNRS Institut FOTON UMR 6082 Rennes35708 France UMR 6226 RennesF-35000 France University of Lille CNRS Centrale Lille Institute Univ. Artois UMR 8181−UCCS− Unité de Catalyse et Chimie du Solide LilleF-59000 France Department of Chemistry University of Nebraska-Lincoln LincolnNE68588 United States

Realizing semiconductors with high symmetry of their crystallographic structures has been a virtue of inorganic materials and has resulted in novel physical behaviors. In contrast, hybrid (organic and inorganic) crystals such as two-dimensional metal halide perovskites exhibit much lower crystal symmetry due to in-plane or out-of-plane octahedral distortions. Despite their amazing ability for photoinduced light emission at room temperature, the Achilles' heel of this attractive class of 2D materials for optoelectronics remains the poor control and lack of performance for charge carrier transport. Inspired by the tremendous charge carrier properties of the 3D cubic perovskite phase (α) of FAPbI3 and combining the use of the appropriate cage cation, the spacer molecule and the temperature and rate of crystallization, we report a new series of FA-based layered two-dimensional perovskites that exhibits the highest theoretically predicted symmetry with a tetragonal P4/mmm space group, resulting in no octahedral distortion in both in-plane and out-of-plane directions. These 2D perovskites present the shortest interlayer distances (4 Å), which results in systematically lower bandgaps (1.7 to 1.8 eV). Finally, the absence of octahedral distortions, results in an exciton diffusion length of 2.5 µm, and a diffusivity of 4.4 cm2s-1, both of which are an order of magnitude larger compared to previously reported 2D perovskites and on par with monolayer transition metal dichalcogenides. © 2025, CC BY.

关键词： Charge carriers

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The broadband 3-year monitoring of the blazar 1ES 1959+650: a SED analysis of the low state

The broadband 3-year monitoring of the blazar 1ES 1959+650: ...

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38th International Cosmic Ray Conference, ICRC 2023

作者： Nanci, Cristina Nigro, Cosimo Arcaro, Cornelia Prandini, Elisa Dorner, Daniela Zanin, Roberta Arbet-Engels, Axel Rosillo, Mireia Nievas D'Ammando, Filippo Bronzini, Ettore Sakurai, Shunsuke 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. Babic, A. Baquero, A. de Almeida, U. Barres Barrio, J.A. Batkovic, I. Baxter, J. Becerra González, J. Bednarek, W. Bernardini, E. Bernardos, M. Bernete, J. Berti, A. Besenrieder, J. Bigongiari, C. Biland, A. Blanch, O. Bonnoli, G. Bošnjak, Z. Bronzini, E. 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'Ammando, F. 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. Godinovic, 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. MartínezChicharro, M. Mas-Aguilar, A. Mazin, D. Menchiari, S. Mender, S. Micanovic, S. Miceli, D. Miener, T. Miranda, J.M. The University of Tokyo Kashiwa Chiba277-8582 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 RomeI-00136 Italy Università di Udine INFN Trieste UdineI- 33100 Italy Max-Planck-Institut für Physik MünchenD-80805 Germany Università di Padova INFN PadovaI-35131 Italy Bellaterra BarcelonaE-08193 Spain Technische Universität Dortmund DortmundD-44221 Germany Zagreb10000 Croatia IPARCOS Institute and EMFTEL Department Universidad Complutense de Madrid MadridE-28040 Spain 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 Bellaterra E-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 INFN Sezione di Bari Dipartimento Interateneo di Fisica dell'Università e del Politecnico di Bari BariI-70125 Italy Croatian MAGIC Group University of Rijeka Faculty of Physics Rijeka51000 Croatia Universität Würzburg WürzburgD-97074 Germany University of Geneva Chemin d'Ecogia 16 VersoixCH-1290 Switzerland Japanese MAGIC Group Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Hiroshima739-8526 Japan Zeuthe

Blazars' Spectral Energy Distribution (SED) consists of two components. In a leptonic interpretation, the low-energy bump is due to synchrotron radiation from accelerated electrons while the high-energy one is produced via inverse Compton scattering of the electrons by lower-energy photons. These come from the synchrotron radiation produced by the same population of electrons emitting at low energy (Synchrotron Self-Compton, SSC, scenario) or from an external photon field. According to hadronic models, the high-energy emission is due to processes involving the protons in the source. Multiwavelength (MWL) long-term monitoring of blazars is key since the SED modelling over time allows the study of the radiative processes during different source states. The blazar 1ES 1959+650 represents an ideal laboratory for that, being bright at all wavelengths and located at low redshift (z=0.047) allowing its detection up to TeV energies. Also, it underwent some flaring episodes in the past. Long-term monitoring of 1ES 1959+650 is ongoing under the coordination of the MAGIC Collaboration. During the last years, the source is experiencing its lowest state ever reached, mainly at very high energies (VHE;E > 100 GeV). This contribution presents the MAGIC+MWL observations of the last 3 years, and the preliminary study focusing on an SSC interpretation of the data. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Synchrotron radiation

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New evidence supporting past dust ejections from active asteroid (4015) Wilson–Harrington

arXiv

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arXiv 2024年

作者： Jin, Sunho Ishiguro, Masateru Geem, Jooyeon Naito, Hiroyuki Takahashi, Jun Akitaya, Hiroshi Kuroda, Daisuke Urakawa, Seitaro Takagi, Seiko Oono, Tatsuharu Sekiguchi, Tomohiko Perna, Davide Ieva, Simone Bach, Yoonsoo P. Imazawa, Ryo Kawabata, Koji S. Watanabe, Makoto Jo, Hangbin Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of SNU Astronomy Research Center Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of Nayoro Observatory 157-1 Nisshin Nayoro Hokkaido096-0066 Japan Center for Astronomy University of Hyogo 407-2 Nishigaichi Sayo Hyogo679-5313 Japan Astronomical Research Center Chiba Institute of Technology 2-17-1 Tsudanuma Narashino Chiba275-0016 Japan Planetary Exploration Research Center Chiba Institute of Technology 2-17-1 Tsudanuma Narashino Chiba275-0016 Japan Hiroshima Astrophysical Science Center Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima Hiroshima739-8526 Japan Bisei Spaceguard Center Japan Spaceguard Association 1716-3 Okura Bisei-cho Ibara Okayama714-1411 Japan Department of Earth and Planetary Sciences Faculty of Science Hokkaido University Kita-ku Sapporo Hokkaido060-0810 Japan Department of Cosmosciences Graduate School of Science Hokkaido University Kita-ku Sapporo Hokkaido060-0810 Japan Asahikawa Campus Hokkaido University of Education Hokumon Hokkaido Asahikawa070-8621 Japan INAF - Osservatorio Astronomico di Roma Via Frascati 33 Monte Porzio CatoneI-00078 Italy 776 Daedeok-daero Yuseong-gu Daejeon34055 Korea Republic of Physics Program Graduate School of Advanced Science and Engineering Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima Hiroshima739-8526 Japan Department of Physics Okayama University of Science 1-1 Ridai-cho Kita-ku Okayama Okayama700-0005 Japan

Context. (4015) Wilson–Harrington (hereafter, WH) was discovered as a comet in 1949 but has a dynamical property consistent with that of a near-Earth asteroid. Although there is a report that the 1949 activity is associated with an ion tail, the cause of the activity has not yet been identified. Aims. This work aims to reveal the mysterious comet-like activity of the near-Earth asteroid. Methods. We conducted new polarimetric observations of WH from May 2022 to January 2023, reanalyses of the photographic plate images taken at the time of its discovery in 1949, and dust tail simulation modelings, where the dust terminal velocity and ejection epoch are taken into account. Results. We found that this object shows polarization characteristics similar to those of low-albedo asteroids. We derived the geometric albedo ranging from pV = 0.076 ± 0.010 to pV = 0.094 ± 0.018 from our polarimetry (the values vary depending on the data used for fitting and the slope-albedo relationship coefficients). In addition, the 1949 image showed an increase in brightness around the nucleus. Furthermore, we found that the color of the tail is consistent with sunlight, suggesting that the 1949 activity is associated with dust ejection. From the dust tail analysis, ∼ 9 × 105 kg of material was ejected episodically at a low velocity equivalent to or even slower than the escape velocity. Conclusions. We conclude that WH is most likely an active asteroid of main belt origin and that the activity in 1949 was likely triggered by mass shedding due to fast rotation. © 2024, CC BY.

关键词： Asteroids

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Benchmarking Diamond Surface Preparation and Fluorination Via Inductively Coupled Plasma-Reactive Ion Etching

SSRN

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SSRN 2024年

作者： Gray, Tia Zhang, Xiang Biswas, Abhijit Terlier, Tanguy Oliveira, Eliezer F. Puthirath, Anand B. Li, Chenxi Pieshkov, Tymofii S. Garratt, Elias J. Neupane, Mahesh R. Pate, Bradford B. Glen, A. Birdwell Ivanov, Tony G. Vajtai, Robert Ajayan, Pulickel M. Department of Materials Science and Nanoengineering Rice University HoustonTX77005 United States SIMS laboratory Shared Equipment Authority Rice University HoustonTX77005 United States SP Bauru17033-360 Brazil Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States DEVCOM Army Research Laboratory RF Devices and Circuits AdelphiMD20783 United States Chemistry Division U.S. Naval Research Laboratory WashingtonDC20375 United States

Diamond, renowned for its exceptional semiconducting properties, stands out as a promising material for high-performance power electronics, optics, quantum, and biosensing technologies. This study methodically investigates the optimization of polycrystalline diamond (PCD) substrate surfaces through Inductively Coupled Plasma Reactive Ion Etching (ICP-RIE). Various parameters, including gaseous species, flow rate, coil power, and bias power were tuned to understand their impact on surface morphology and chemistry. A thorough characterization, encompassing chemical, spectroscopic, and microscopic methods, shed light on the effects of different ICP-RIE conditions on surface properties. CF4/O2 plasma emerged as a viable treatment for achieving smooth PCD surfaces with minimal etch pit formation. Most notably, surface fluorination, a critical aspect of increasing chemical and thermal stability, was successfully accomplished using CF4, SF6, and other F-containing plasmas. The fluorine concentration and surface chemistry variations were studied, with high resolution X-ray Photoelectron Spectroscopy unveiling differences amongst the sp2 C phase, sp3 C phase, C-O, C=O, and C-F bonds. Time-of-flight secondary Ion Mass Spectrometry (ToF-SIMS) and depth-profile analysis unveiled a consistent surface fluorination pattern with CF4/O2 treatment. Furthermore, contact angle measurements showcased heightened hydrophobicity. This study provides valuable insights into precise diamond surface engineering, important for the development of future diamond-based semiconductor technologies. © 2024, The Authors. All rights reserved.

关键词： Surface morphology

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The TESS-Keck Survey. XIX. A Warm Transiting Sub-Saturn Mass Planet and a non-Transiting Saturn Mass Planet Orbiting a Solar Analog

arXiv

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arXiv 2024年

作者： Hill, Michelle L. Kane, Stephen R. Dalba, Paul A. MacDougall, Mason Fetherolf, Tara Li, Zhexing Pidhorodetska, Daria Batalha, Natalie M. Crossfield, Ian J.M. Dressing, Courtney Fulton, Benjamin Howard, Andrew W. Huber, Daniel Isaacson, Howard Petigura, Erik A. Robertson, Paul Weiss, Lauren M. Behmard, Aida Beard, Corey Chontos, Ashley Dai, Fei Giacalone, Steven Hirsch, Lea A. Holcomb, Rae Lubin, Jack Mayo, Andrew W. Močnik, Teo Murphy, M. Joseph Akana Polanski, Alex S. Rosenthal, Lee J. Rubenzahl, Ryan A. Scarsdale, Nicholas Turtelboom, Emma V. Van Zandt, Judah Bieryla, Allyson Ciardi, David R. Eastman, Jason D. Falk, Ben Hesse, Katharine M. Latham, David W. Livingston, John Matson, Rachel A. Matthews, Elisabeth Ricker, George R. Rudat, Alexander Schlieder, Joshua E. Seager, S. Winn, Joshua N. Department of Earth and Planetary Sciences University of California RiversideCA92521 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Department of Physics & Astronomy University of California Los Angeles Los AngelesCA90095 United States Department of Physics California State University San MarcosCA92096 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95060 United States Department of Physics & Astronomy University of Kansas 1082 Malott 1251 Wescoe Hall Dr. LawrenceKS66045 United States 501 Campbell Hall University of California at Berkeley BerkeleyCA94720 United States NASA Exoplanet Science Institute Caltech-IPAC MC 314-6 1200 E. California Blvd. PasadenaCA91125 United States Department of Astronomy California Institute of Technology PasadenaCA91125 United States Institute for Astronomy University of Hawai‘i 2680 Woodlawn Drive HonoluluHI96822 United States School of Physics University of Sydney NSW2006 Australia Department of Astronomy University of California Berkeley BerkeleyCA94720 United States Centre for Astrophysics University of Southern Queensland ToowoombaQLD Australia Department of Physics & Astronomy University of California Irvine IrvineCA92697 United States Department of Astrophysics American Museum of Natural History 200 Central Park West ManhattanNY10024 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08540 United States Division of Geological and Planetary Sciences 1200 E California Blvd PasadenaCA91125 United States Kavli Institute for Particle Astrophysics and Cosmology Stanford University StanfordCA94305 United States Gemini Observatory NSF’s NOIRLab 670 N. A’ohoku Place HiloHI96720 United States Department of Physics and Astronomy University of Kansas LawrenceKS66045 United States Department of Astronomy 501 Campbell Hall Universit

The Transiting Exoplanet Survey Satellite (TESS) continues to dramatically increase the number of known transiting exoplanets, and is optimal for monitoring bright stars amenable to radial velocity (RV) and atmospheric follow-up observations. TOI-1386 is a solar-type (G5V) star that was detected via TESS photometry to exhibit transit signatures in three sectors with a period of 25.84 days. We conducted follow-up RV observations using Keck/HIRES as part of the TESS-Keck Survey (TKS), collecting 64 RV measurements of TOI-1386 with the HIRES spectrograph over 2.5 years. Our combined fit of the TOI-1386 photometry and RV data confirm the planetary nature of the detected TESS signal, and provide a mass and radius for planet b of 0.148 ±0.019 MJ and 0.540 ±0.017 RJ, respectively, marking TOI-1386 b as a warm sub-Saturn planet. Our RV data further reveal an additional outer companion, TOI-1386 c, with an estimated orbital period of 227.6 days and a minimum mass of 0.309±0.038 MJ. The dynamical modeling of the system shows that the measured system architecture is long-term stable, although there may be substantial eccentricity oscillations of the inner planet due to the dynamical influence of the outer planet. Copyright © 2024, The Authors. All rights reserved.

关键词： Satellites

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Components of star formation in NGC 253: Non-negative Matrix Factorization Analysis with the ALCHEMI integrated intensity images

arXiv

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arXiv 2024年

作者： Kishikawa, Ryo Harada, Nanase Saito, Toshiki Aalto, Susanne Colzi, Laura Gorski, Mark Henkel, Christian Mangum, Jeffrey G. Martín, Sergio Muller, Sebastian Nishimura, Yuri Rivilla, Víctor M. Sakamoto, Kazushi der Werf, Paul VAN Viti, Serena Department of Physics Tokyo Metropolitan University 1-1 Minami-Osawa Hachioji Tokyo192-0397 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Astronomical Science Program Graduate Institute for Advanced Studies SOKENDAI 2-21-1 Osawa Mitaka Tokyo181-1855 Japan Faculty of Global Interdisciplinary Science and Innovation Shizuoka University 836 Ohya Suruga-ku Shizuoka422-8529 Japan Department of Space Earth and Environment Chalmers University of Technology Onsala Space Observatory OnsalaSE-439 92 Sweden CSIC-INTA Ctra. de Ajalvir Km. 4 Torrejón de Ardoz Madrid28850 Spain Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 Bonn53121 Germany Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi830011 China National Radio Astronomy Observatory 520 Edgemont Road CharlottesvilleVA22903-2475 United States European Southern Observatory Alonso de Córdova 3107 Vitacura Santiago763-0355 Chile Joint ALMA Observatory Alonso de Córdova 3107 Vitacura Santiago763-0355 Chile Institute of Astronomy Graduate School of Science The University of Toky 2-21-1 Osawa Mitaka Tokyo181-0015 Japan Institute of Astronomy and Astrophysics Academia Sinica 11F of AS/NTU Astronomy-Mathematics Building No.1 Sec. 4 Roosevelt Rd Taipei106216 Taiwan Leiden Observatory Leiden University P.O. Box 9513 Leiden2300 RA Netherlands Physics and Astronomy Department University College London Gower St LondonWC1E 6BT United Kingdom

It is essential to examine the physical or chemical properties of molecular gas in starburst galaxies to reveal the underlying mechanisms characterizing starbursts. We used non-negative matrix factorization (NMF) to extract individual molecular or physical components involved in the star formation process in NGC 253. We used images of 148 transitions from 44 different species of the ALMA large program ALCHEMI. Additionally, we included the continuum images at ALMA Bands 3 and 7 from the same dataset. For the five NMF components (NF1–5), we obtained that their distributions correspond to various basic phenomena related to star formation: i) low-density gas extended through the galactic central molecular zone (NF2), ii) shocks (NF3), iii) starburst regions (NF4), and iv) young star-forming regions (NF5). The other component (NF1) is related to excitation;three components obtained by NMF (NF3, 1, and 5) show a strong dependence upon the upper state energies of transitions, and represent low-, intermediate-, and high-excitation, respectively. We also compared our results using principal component analysis (PCA) previously applied to the same dataset. Molecular components extracted from NMF are similar to the ones obtained from PCA. However, NMF is better at extracting components associated with a single physical component, while a single component in PCA usually contains information on multiple physical components. This is especially true for features with weak intensities like emission from outflows. Our results suggest that NMF can be one of promising methods interpreting molecular line survey data, especially in the upcoming era of wide-band receivers. © 2024, CC BY.

关键词： Non-negative matrix factorization

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JWST/NIRSpec spectroscopy of intermediate-mass quiescent galaxies at z ∼ 3–4

arXiv

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arXiv 2024年

作者： Sato, Riku A. Inoue, Akio K. Harikane, Yuichi Shimakawa, Rhythm Sugahara, Yuma Tamura, Yoichi Hashimoto, Takuya Ito, Kei Yamanaka, Satoshi Mawatari, Ken Fudamoto, Yoshinobu Ren, Yi W. Department of Pure and Applied Physics Graduate School of Advanced Science and Engineering Faculty of Science and Engineering Waseda University 3-4-1 Okubo Shinjuku Tokyo169-8555 Japan Waseda research Institute of Science and Engineering Faculty of Science and Engineering Waseda University 3-4-1 Okubo Shinjuku Tokyo169-8555 Japan Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwanoha Chiba Kashiwa277-8582 Japan Waseda University 1-21-1 Nishi-Waseda Shinjuku Tokyo169-0051 Japan Center for Data Science Waseda University 1-6-1 Nishi-Waseda Shinjuku Tokyo169-0051 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181–8588 Japan Department of Physics Graduate School of Science Nagoya University Furo Chikusa Aichi Nagoya464-8602 Japan Division of Physics Faculty of Pure and Applied Sciences University of Tsukuba Ibaraki Tsukuba305-8571 Japan Faculty of Pure and Applied Sciences University of Tsukuba Ibaraki Tsukuba305-8571 Japan Department of Astronomy Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-0033 Japan General Education Department National Institute of Technology Toba College 1-1 Ikegami-cho Mie Toba517-8501 Japan Center for Frontier Science Chiba University 1-33 Yayoi-cho Inage-ku Chiba263-8522 Japan

We present the analysis of three intermediate-mass quiescent galaxies (QGs) with stellar masses of ∼ 1010M☉ at redshifts z ∼ 3–4 using NIRSpec low-resolution spectroscopy. Utilising the SED fitting code BAGPIPES, we confirm these target galaxies are consistent with quiescent population, with their specific star formation rates (sSFR) falling below 2-dex the star-forming main sequence at the same redshifts. Additionally, we identify these QGs to be less massive than those discovered in previous works, particularly prior to the JWST era. Two of our target galaxies exhibit the potentially-blended Hα+[NII] emission line within their spectra with S/N > 5. We discuss whether this feature comes from an Active Galactic Nucleus (AGN) or star formation although future high-resolution spectroscopy is required to reach a conclusion. One of the target galaxies is covered by JWST/NIRCam imaging of the PRIMER survey. Using the 2D profile fitting code Galfit, we examine its morphology, revealing a disc-like profile with a Sérsic index of n = 1.1 ± 0.1. On the size–mass relation, we find a potential distinction between less-massive (log10 (M∗/M☉) 10 (M∗/M☉) > 10.3) QGs in their evolutionary pathways. The derived quenching timescales for our targets are less than 1 Gyr. This may result from these galaxies being quenched by AGN feedback, supporting the AGN scenario of the emission line features. Copyright © 2024, The Authors. All rights reserved.

关键词： Stars

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Identified charged-hadron production in p+Al, He3+Au, and Cu+Au collisions at sNN=200GeV and in U+U collisions at sNN=193GeV

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Physical Review C 2024年第5期109卷 054910-054910页

作者： N. J. Abdulameer U. Acharya A. Adare C. Aidala N. N. Ajitanand Y. Akiba R. Akimoto J. Alexander M. Alfred V. Andrieux K. Aoki N. Apadula H. Asano E. T. Atomssa T. C. Awes B. Azmoun V. Babintsev M. Bai X. Bai N. S. Bandara B. Bannier K. N. Barish S. Bathe V. Baublis C. Baumann S. Baumgart A. Bazilevsky M. Beaumier S. Beckman R. Belmont A. Berdnikov Y. Berdnikov L. Bichon D. Black B. Blankenship D. S. Blau J. S. Bok V. Borisov K. Boyle M. L. Brooks J. Bryslawskyj H. Buesching V. Bumazhnov S. Butsyk S. Campbell V. Canoa Roman R. Cervantes C.-H. Chen D. Chen M. Chiu C. Y. Chi I. J. Choi J. B. Choi S. Choi P. Christiansen T. Chujo V. Cianciolo Z. Citron B. A. Cole M. Connors R. Corliss Y. Corrales Morales N. Cronin N. Crossette M. Csanád T. Csörgő L. D'Orazio T. W. Danley A. Datta M. S. Daugherity G. David C. T. Dean K. DeBlasio K. Dehmelt A. Denisov A. Deshpande E. J. Desmond L. Ding A. Dion P. B. Diss D. Dixit V. Doomra J. H. Do O. Drapier A. Drees K. A. Drees J. M. Durham A. Durum H. En'yo T. Engelmore A. Enokizono R. Esha K. O. Eyser B. Fadem W. Fan N. Feege D. E. Fields M. Finger, Jr. M. Finger D. Firak D. Fitzgerald F. Fleuret S. L. Fokin J. E. Frantz A. Franz A. D. Frawley Y. Fukao Y. Fukuda T. Fusayasu K. Gainey P. Gallus C. Gal P. Garg A. Garishvili I. Garishvili H. Ge M. Giles F. Giordano A. Glenn X. Gong M. Gonin Y. Goto R. Granier de Cassagnac N. Grau S. V. Greene M. Grosse Perdekamp Y. Gu T. Gunji T. Guo H. Guragain T. Hachiya J. S. Haggerty K. I. Hahn H. Hamagaki H. F. Hamilton J. Hanks S. Y. Han M. Harvey S. Hasegawa T. O. S. Haseler K. Hashimoto R. Hayano T. K. Hemmick T. Hester X. He J. C. Hill K. Hill A. Hodges R. S. Hollis K. Homma B. Hong T. Hoshino N. Hotvedt J. Huang T. Ichihara Y. Ikeda K. Imai Y. Imazu M. Inaba A. Iordanova D. Isenhower A. Isinhue D. Ivanishchev B. V. Jacak S. J. Jeon M. Jezghani X. Jiang Z. Ji B. M. Johnson K. S. Joo D. Jouan D. S. Jumper J. Kamin S. Kanda B. H. Kang J. H. Kang J. S. Kang D. Kapukchyan J. Kapustinsky S. Karthas D. Kawall A. V. Kazantsev J. A. Key V. Khachatrya Debrecen University H-4010 Debrecen Egyetem tér 1 Hungary Georgia State University Atlanta Georgia 30303 USA University of Colorado Boulder Colorado 80309 USA Los Alamos National Laboratory Los Alamos New Mexico 87545 USA Department of Physics University of Michigan Ann Arbor Michigan 48109 USA Chemistry Department State University of New York at Stony Brook Stony Brook New York 11794 USA RIKEN Nishina Center for Accelerator-Based Science Wako Saitama 351-0198 Japan RIKEN BNL Research Center Brookhaven National Laboratory Upton New York 11973 USA Center for Nuclear Study Graduate School of Science University of Tokyo 7-3-1 Hongo Bunkyo Tokyo 113-0033 Japan Department of Physics and Astronomy Howard University Washington DC 20059 USA KEK High Energy Accelerator Research Organization Tsukuba Ibaraki 305-0801 Japan Iowa State University Ames Iowa 50011 USA Department of Physics and Astronomy State University of New York at Stony Brook Stony Brook New York 11794 USA Kyoto University Kyoto 606-8502 Japan Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Physics Department Brookhaven National Laboratory Upton New York 11973 USA IHEP Protvino State Research Center of Russian Federation Institute for High Energy Physics Protvino 142281 Russia Collider-Accelerator Department Brookhaven National Laboratory Upton New York 11973 USA Science and Technology on Nuclear Data Laboratory China Institute of Atomic Energy Beijing 102413 People's Republic of China Department of Physics University of Massachusetts Amherst Massachusetts 01003 USA University of California-Riverside Riverside California 92521 USA Baruch College City University of New York New York New York 10010 USA Petersburg Nuclear Physics Institute Gatchina Leningrad Region 188300 Russia Physics and Astronomy Department University of North Carolina at Greensboro Greensboro North Carolina 27412 USA Vanderbilt University Nashville Tennessee 37235 USA Saint Petersburg Stat

The PHENIX experiment has performed a systematic study of identified charged-hadron (π±, K±, p, p¯) production at midrapidity in p+Al, He3+Au, and Cu+Au collisions at sNN=200GeV and U+U collisions at sNN=193GeV. Identified charged-hadron invariant transverse-momentum (pT) and transverse-mass (mT) spectra are presented and interpreted in terms of radially expanding thermalized systems. The particle ratios of K/π and p/π have been measured in different centrality ranges of large (Cu+Au and U+U) and small (p+Al and He3+Au) collision systems. The values of K/π ratios measured in all considered collision systems were found to be consistent with those measured in p+p collisions. However, the values of p/π ratios measured in large collision systems reach the values of ≈0.6, which is a factor of ≈2 larger than in p+p collisions. These results can be qualitatively understood in terms of the baryon enhancement expected from hadronization by recombination. Identified charged-hadron nuclear-modification factors (RAB) are also presented. Enhancement of proton RAB values over meson RAB values was observed in central He3+Au, Cu+Au, and U+U collisions. The proton RAB values measured in the p+Al collision system were found to be consistent with RAB values of ϕ, π±, K±, and π0 mesons, which may indicate that the size of the system produced in p+Al collisions is too small for recombination to cause a noticeable increase in proton production.

关键词： Hadron production Relativistic heavy-ion collisions Hadrons Kaons Pions Protons

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Polarimetric signature of the oceans as detected by near-infrared Earthshine observations

arXiv

引用

arXiv 2021年

作者： Takahashi, Jun Itoh, Y. Matsuo, T. Oasa, Y. Bach, Y.P. Ishiguro, M. Center for Astronomy University of Hyogo 407-2 Nishigaichi Sayo Hyogo679-5313 Japan Graduate School of Science Nagoya University Furo-cho Chikusa-ku Nagoya464-8602 Japan Faculty of Education Graduate School of Science and Engineering Saitama University 255 Shimo-Okubo Sakura-ku Saitama338-8570 Japan Astronomy Program Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of SNU Astronomy Research Center Department of Physics and Astronomy Seoul National University 1 Gwanak-ro Gwanak-gu Seoul08826 Korea Republic of

Context. The discovery of an extrasolar planet with an ocean has crucial importance in the search for life beyond Earth. The polarimetric detection of specularly reflected light from a smooth liquid surface is anticipated theoretically, though the polarimetric signature of Earth's oceans has not yet been conclusively detected in disk-integrated planetary light. Aims. We aim to detect and measure the polarimetric signature of the Earth's oceans. Methods. We conducted near-infrared polarimetry for lunar Earthshine and collected data on 32 nights with a variety of ocean fractions in the Earthshine-contributing region. Results. A clear positive correlation was revealed between the polarization degree and ocean fraction. We found hourly variations in polarization in accordance with rotational transition of the ocean fraction. The ratios of the variation to the typical polarization degree were as large as ∼0.2-1.4. Conclusions. Our observations provide plausible evidence of the polarimetric signature attributed to Earth's oceans. Near-infrared polarimetry may be considered a prospective technique in the search for exoplanetary oceans. Copyright © 2021, The Authors. All rights reserved.

关键词： Polarimeters

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