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arXiv 2022年

作者： Nasim, Syeda S. Fabj, Gaia Caban, Freddy Secunda, Amy Ford, K.E. Saavik McKernan, Barry Bellovary, Jillian M. Leigh, Nathan W.C. Lyra, Wladimir Department of Physics Missouri University of Science and Technology RollaMO65409 United States Department of Astrophysics American Museum of Natural History New YorkNY10024 United States Niels Bohr International Academy The Niels Bohr Institute Blegdamsvej 17 Copenhagen2100 Denmark Department of Physics Stony Brook University State University of New York Stony BrookNY11794 United States Department of Astrophysical Sciences Princeton University Peyton Hall PrincetonNJ08544 United States Department of Science Borough of Manhattan Community College City University of New York New YorkNY10007 United States Physics Program CUNY Graduate Center City University of New York New YorkNY10016 United States Astrophysics Program CUNY Graduate Center City University of New York New YorkNY10016 United States Department of Physics Queensborough Community College City University of New York BaysideNY11364 United States Departamento de Astronomía Facultad Ciencias Físicas y Matemáticas Universidad de Concepción Concepción403000 Chile Department of Astronomy New Mexico State University Las CrucesNM88003 United States

Stars and stellar remnants orbiting a supermassive black hole (SMBH) can interact with an active galactic nucleus (AGN) disc. Over time, prograde orbiters (inclination i ◦) decrease inclination, as well as semi-major axis (a) and eccentricity (e) until orbital alignment with the gas disc (‘disc capture’). Captured stellar-origin black holes (sBH) add to the embedded AGN population which drives sBH-sBH mergers detectable in gravitational waves using LIGO-Virgo-KAGRA (LVK) or sBH-SMBH mergers detectable with LISA (Laser Interferometer Space Antenna). Captured stars can be tidally disrupted by sBH or the SMBH or rapidly grow into massive ‘immortal’ stars. Here, we investigate the behaviour of polar and retrograde orbiters (i ≥ 90◦) interacting with the disc. We show that retrograde stars are captured faster than prograde stars, flip to prograde orientation (i ◦) during capture, and decrease a dramatically towards the SMBH. For sBH, we find a critical angle iret ∼ 113◦, below which retrograde sBH decay towards embedded prograde orbits (i → 0◦), while for io > iret sBH decay towards embedded retrograde orbits (i → 180◦). sBH near polar orbits (i ∼ 90◦) and stars on nearly embedded retrograde orbits (i ∼ 180◦) show the greatest decreases in a. Whether a star is captured by the disc within an AGN lifetime depends primarily on disc density, and secondarily on stellar type and initial a. For sBH, disc capture-time is longest for polar orbits, low mass sBH and lower density discs. Larger mass sBH should typically spend more time in AGN discs, with implications for the embedded sBH spin distribution. Copyright © 2022, The Authors. All rights reserved.

关键词： Gravity waves

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Reprocessing the NEAT Dataset: Preliminary Results

arXiv

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arXiv 2025年

作者： Nugent, C.R. Bauer, J.M. Benitez, O. Blain, M. D’Souza, N. Garimella, S. Goldwater, M. Kim, Y. Larsen, H.C.G. Linder, T. Mackowiak, K. McGinnis, Z. Pan, E. Pedersen, C.C. Sadhwani, P. Spoto, F. Tan, N.J. Vereš, P. Xue, C. Olin College of Engineering 1000 Olin Way NeedhamMA02492 United States Department of Astronomy University of Maryland College ParkMD20742 United States Department of Earth and Space Sciences College of the Canyons Santa ClaritaCA91355 United States MIT-WHOI Joint Program in Applied Ocean Science & Engineering Cambridge and Woods Hole MA United States Department of Applied Ocean Physics & Engineering Woods Hole Oceanographic Institution 266 Woods Hole Road MS #55 Woods HoleMA02543-1050 United States Aalborg University Fibigerstræde 16 Aalborg9220 Denmark Planetary Science Institute TucsonAZ85719 United States Minor Planet Center Smithsonian Astrophysical Observatory 60 Garden Street CambridgeMA02138 United States School of Physical and Chemical Sciences Te Kura Matū University of Canterbury Private Bag 4800 Christchurch8140 New Zealand

We have created a new image analysis pipeline to reprocess images taken by the Near Earth Asteroid Tracking survey and have applied it to ten nights of observations. This work is the first large-scale reprocessing of images from an asteroid discovery survey in which thousands of archived images are re-calibrated, searched for minor planets, and resulting observations are reported to the Minor Planet Center. We describe the software used to extract, calibrate, and clean sources from the images, including specific techniques that accommodate the unique features of these archival images. This pipeline is able to find fainter asteroids than the original pipeline. © 2025, CC BY.

关键词： Asteroids

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Outcomes from a Workshop on a National Center for Quantum Education

arXiv

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arXiv 2024年

作者： Barnes, Edwin Bennett, Michael B. Boltasseva, Alexandra Borish, Victoria Brown, Bennett Carr, Lincoln D. Ceballos, Russell R. Dukes, Faith Easton, Emily W. Economou, Sophia E. Edwards, E.E. Finkelstein, Noah D. Fracchiolla, C. Franklin, Diana Freericks, J.K. Goss, Valerie Hannum, Mark Holincheck, Nancy Kelly, Angela M. Lanes, Olivia Lewandowski, H.J. Matsler, Karen Jo Mercurio, Emily Montaño, Inès Murdock, Maajida Peltz, Kiera Perron, Justin K. Richardson, Christopher J.K. Rosenberg, Jessica L. Ross, Richard S. Ryu, Minjung Samuel, Raymond E. Schrode, Nicole Schwamberger, Susan Searles, Thomas A. Singh, Chandralekha Tingle, Alexandra Zwickl, Benjamin M. Department of Physics Virginia Tech Center for Quantum Information Science and Engineering Virginia Tech 850 West Campus Drive BlacksburgVA24061 United States Q-SEnSE NSF QLCI University of Colorado 440 UCB BoulderCO80301 United States Elmore Family School of Electrical and Computer Engineering Birck Nanotechnology Center Purdue Quantum Science and Engineering Institute Purdue University 610 Purdue Mall West LafayetteIN47907 United States Quantum Science Center A National Quantum Information Science Research Center of The U.S. Department of Energy Oak Ridge National Laboratory 1 Bethel Valley Road Oak RidgeTN37830 United States JILA National Institute of Standards and Technology the University of Colorado BoulderCO80309 United States Department of Physics University of Colorado 390 UCB BoulderCO80309 United States QuSTEAM 510 Ronalds St. Iowa CityIA52245 United States Quantum Engineering Program Department of Physics Colorado School of Mines 1523 Illinois St. GoldenCO80401 United States QuSTEAM Non-Profit Wilbur Wright College City Colleges of Chicago 4300 N Narragansett Ave ChicagoIL60634 United States Government and Community Relations Office - K-12 Programs Lawrence Berkeley National Laboratory 1 Cyclotron Road BerkeleyCA United States Chicago Quantum Exchange 5235 S. Harper Court ChicagoIL60615 United States Department of Physics Virginia Tech 850 West Campus Drive BlacksburgVA24060 United States Department of Electrical and Computer Engineering Duke Quantum Center Duke University Duke University 130 Hudson Hall DurhamNC27708 United States American Physical Society 555 12th St. NW WashingtonDC20004 United States Computer Science University of Chicago 5730 S. Ellis Ave. ChicagoIL60637 United States Department of Physics Georgetown University 552 Reiss Science Building WashingtonDC20057 United States Chemistry Physics and Engineering Studies Chicago State University 9501 S. King Drive WSC 309 ChicagoIL606

In response to numerous programs seeking to advance quantum education and workforce development in the United States, experts from academia, industry, government, and professional societies convened for a National Science Foundation-sponsored workshop in February 2024 to explore the benefits and challenges of establishing a national center for quantum education. Broadly, such a center would foster collaboration and build the infrastructure required to develop a diverse and quantum-ready workforce. The workshop discussions centered around how a center could uniquely address gaps in public, K-12, and undergraduate quantum information science and engineering (QISE) education. Specifically, the community identified activities that, through a center, could lead to an increase in student awareness of quantum careers, boost the number of educators trained in quantum-related subjects, strengthen pathways into quantum careers, enhance the understanding of the U.S. quantum workforce, and elevate public engagement with QISE. Core proposed activities for the center include professional development for educators, coordinated curriculum development and curation, expanded access to educational laboratory equipment, robust evaluation and assessment practices, network building, and enhanced public engagement with quantum science. © 2024, CC BY.

关键词： Students

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Detections of [C ii] 158 µm and [O iii] 88 µm in a Local Lyman Continuum Emitter, Mrk 54, and its Implications to High-redshift ALMA Studies

arXiv

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arXiv 2023年

作者： Ura, Ryota Hashimoto, Takuya Inoue, Akio K. Fadda, Dario Hayes, Matthew Puschnig, Johannes Zackrisson, Erik Tamura, Yoichi Matsuo, Hiroshi Mawatari, Ken Fudamoto, Yoshinobu Hagimoto, Masato Kuno, Nario Sugahara, Yuma Yamanaka, Satoshi Bakx, Tom J.L.C. Nakazato, Yurina Usui, Mitsutaka Yajima, Hidenobu Yoshida, Naoki 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 Physics School of Advanced Science and Engineering Waseda University 3-4-1 Okubo Shinjuku Tokyo169-8555 Japan Waseda Research Institute for Science and Engineering Faculty of Science and Engineering Waseda University 3-4-1 Okubo Shinjuku Tokyo169-8555 Japan SOFIA Science Center Universities Space Research Association MS 232-11 Moffett Field CA94035 United States The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova StockholmSE-10691 Sweden Argelander-Institut für Astronomie Auf dem Hügel 71 BonnD-53121 Germany Observational Astrophysics Department of Physics and Astronomy Uppsala University Box 516 UppsalaSE-751 20 Sweden Department of Physics Graduate School of Science Nagoya University Nagoya464-8602 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan General Education Department National Institute of Technology Toba College 1-1 Ikegami-cho Toba Mie517-8501 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo Japan Department of Physics School of Science The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo113-0033 Japan Center for Computational Sciences University of Tsukuba Ten-nodai 1-1-1 Tsukuba Ibaraki305-8577 Japan UT Institute for Advanced Study The University of Tokyo Chiba Kashiwa277-8583 Japan

We present integral field, far-infrared (FIR) spectroscopy of Mrk 54, a local Lyman Continuum Emitter (LCE), obtained with FIFI-LS on the Stratospheric Observatory for Infrared astronomy. This is only the second time, after Haro 11, that [C ii] 158 µm and [O iii] 88 µm spectroscopy of the known LCEs have been obtained. We find that Mrk 54 has a strong [C ii] emission that accounts for ∼ 1% of the total FIR luminosity, whereas it has only moderate [O iii] emission, resulting in the low [O iii]/[C ii] luminosity ratio of 0.22 ± 0.06. In order to investigate whether [O iii]/[C ii] is a useful tracer of fesc (LyC escape fraction), we examine the correlations of [O iii]/[C ii] and (i) the optical line ratio of O32 ≡ [O iii] 5007 Å/[O ii] 3727 Å, (ii) specific star formation rate, (iii) [O iii] 88 µm/[O i] 63 µm ratio, (iv) gas phase metallicity, and (v) dust temperature based on a combined sample of Mrk 54 and the literature data from the Herschel Dwarf Galaxy Survey and the LITTLE THINGS Survey. We find that galaxies with high [O iii]/[C ii] luminosity ratios could be the result of high ionization (traced by O32), bursty star formation, high ionized-to-neutral gas volume filling factors (traced by [O iii] 88 µm/[O i] 63 µm), and low gas-phase metallicities, which is in agreement with theoretical predictions. We present an empirical relation between the [O iii]/[C ii] ratio and fesc based on the combination of the [O iii]/[C ii] and O32 correlation, and the known relation between O32 and fesc. The relation implies that high-redshift galaxies with high [O iii]/[C ii] ratios revealed by ALMA may have fesc & 0.1, significantly contributing to the cosmic reionization. © 2023, CC0.

关键词： Luminance

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Early Release Science of the exoplanet WASP-39b with JWST NIRCam

arXiv

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arXiv 2022年

作者： Ahrer, Eva-Maria Stevenson, Kevin B. Mansfield, Megan Moran, Sarah E. Brande, Jonathan Morello, Giuseppe Murray, Catriona A. Nikolov, Nikolay K. Petit dit de la Roche, Dominique J.M. Schlawin, Everett Wheatley, Peter J. Zieba, Sebastian Batalha, Natasha E. Damiano, Mario Goyal, Jayesh M. Lendl, Monika Lothringer, Joshua D. Mukherjee, Sagnick Ohno, Kazumasa Batalha, Natalie M. Battley, Matthew P. Bean, Jacob L. Beatty, Thomas G. Benneke, Björn Berta-Thompson, Zachory K. Carter, Aarynn L. Cubillos, Patricio E. Daylan, Tansu Espinoza, Néstor Gao, Peter Gibson, Neale P. Gill, Samuel Harrington, Joseph Hu, Renyu Kreidberg, Laura Lewis, Nikole K. Line, Michael R. López-Morales, Mercedes Parmentier, Vivien Powell, Diana K. Sing, David K. Tsai, Shang-Min Wakeford, Hannah R. Welbanks, Luis Alam, Munazza K. Alderson, Lili Allen, Natalie H. Anderson, David R. Barstow, Joanna K. Bayliss, Daniel Bell, Taylor J. Blecic, Jasmina Bryant, Edward M. Burleigh, Matthew R. Carone, Ludmila Casewell, S.L. Changeat, Quentin Chubb, Katy L. Crossfield, Ian J.M. Crouzet, Nicolas Decin, Leen Désert, Jean-Michel Feinstein, Adina D. Flagg, Laura Fortney, Jonathan J. Gizis, John E. Heng, Kevin Iro, Nicolas Kempton, Eliza M.-R. Kendrew, Sarah Kirk, James Knutson, Heather A. Komacek, Thaddeus D. Lagage, Pierre-Olivier Leconte, Jérémy Lustig-Yaeger, Jacob MacDonald, Ryan J. Mancini, Luigi May, E.M. Mayne, N.J. Miguel, Yamila Mikal-Evans, Thomas Molaverdikhani, Karan Palle, Enric Piaulet, Caroline Rackham, Benjamin V. Redfield, Seth Rogers, Laura K. Roy, Pierre-Alexis Rustamkulov, Zafar Shkolnik, Evgenya L. Sotzen, Kristin S. Taylor, Jake Tremblin, P. Tucker, Gregory S. Turner, Jake D. de Val-Borro, Miguel Venot, Olivia Zhang, Xi Centre for Exoplanets and Habitability University of Warwick Coventry United Kingdom Department of Physics University of Warwick Coventry United Kingdom Johns Hopkins APL LaurelMD United States Steward Observatory University of Arizona TucsonAZ United States NHFP Sagan Fellow United States Lunar and Planetary Laboratory University of Arizona TucsonAZ United States Department of Physics & Astronomy University of Kansas LawrenceKS United States Tenerife Spain Tenerife Spain INAF- Palermo Astronomical Observatory Piazza del Parlamento Palermo Italy Department of Astrophysical and Planetary Sciences University of Colorado BoulderCO United States Space Telescope Science Institute BaltimoreMD United States Département d'Astronomie Université de Genève Sauverny Switzerland Max Planck Institute for Astronomy Heidelberg Germany Leiden Observatory University of Leiden Leiden Netherlands NASA Ames Research Center Moffett Field CA United States Jet Propulsion Laboratory PasadenaCA United States HBNI Odisha India Department of Physics Utah Valley University OremUT United States Department of Astronomy & Astrophysics University of California Santa Cruz Santa CruzCA United States Astrobiology Program UC Santa Cruz Santa CruzCA United States Department of Astronomy & Astrophysics University of Chicago ChicagoIL United States Department of Astronomy University of Wisconsin-Madison MadisonWI United States Department of Physics Institute for Research on Exoplanets Université de Montréal MontrealQC Canada Space Research Institute Austrian Academy of Sciences Graz Austria INAF Osservatorio Astrofisico di Torino Pino Torinese Italy Department of Astrophysical Sciences Princeton University PrincetonNJ United States LSSTC Catalyst Fellow Department of Physics & Astronomy Johns Hopkins University BaltimoreMD United States Earth and Planets Laboratory Carnegie Institution for Science WashingtonDC United States School of Physics Trinity Col

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopye.g., 1,2 provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species;however, this requires broad wavelength coverage, moderate spectral resolution, and high precision that, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST’s Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0 – 4.0 µm, exhibit minimal systematics, and reveal well-defined molecular absorption features in the planet’s spectrum. Specifically, we detect gaseous H2O in the atmosphere and place an upper limit on the abundance of CH4. The otherwise prominent CO2 feature at 2.8 µm is largely masked by H2O. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1–100× solar (i.e., an enrichment of elements heavier than helium relative to the Sun) and a sub-stellar carbon-to-oxygen (C/O) ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formatione.g., 3,4 or disequilibrium processes in the upper atmospheree.g., 5,6 © 2022, CC BY.

关键词： Spectral resolution

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Spatial Heterogeneities in Structural Temperature Cause Kovacs’ Expansion Gap Paradox in Aging of Glasses

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Physical Review Letters 2020年第9期124卷 095501-095501页

作者： Matteo Lulli Chun-Shing Lee Hai-Yao Deng Cho-Tung Yip Chi-Hang Lam Department of Applied Physics Hong Kong Polytechnic University Hong Kong China Department of Mechanics and Aerospace Engineering Southern University of Science and Technology Shenzhen Guangdong 518055 China School of Physics and Astronomy The University of Manchester Manchester M13 9PL United Kingdom School of Physics and Astronomy Cardiff University The Parade Cardiff CF24 3AA United Kingdom School of Science Harbin Institute of Technology Shenzhen Graduate School Shenzhen Guangdong 518055 China

Volume and enthalpy relaxation of glasses after a sudden temperature change has been extensively studied since Kovacs’ seminal work. One observes an asymmetric approach to equilibrium upon cooling versus heating and, more counterintuitively, the expansion gap paradox, i.e., a dependence on the initial temperature of the effective relaxation time even close to equilibrium when heating. Here, we show that a distinguishable-particle lattice model can capture both the asymmetry and the paradox. We quantitatively characterize the energetic states of the particle configurations using a physical realization of the fictive temperature called the structural temperature, which, in the heating case, displays a strong spatial heterogeneity. The system relaxes by nucleation and expansion of warmer mobile domains having attained the final temperature, against cooler immobile domains maintained at the initial temperature. A small population of these cooler regions persists close to equilibrium, thus explaining the paradox.

关键词： Aging Glassy systems Lattice models in condensed matter

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Direct Measurement of the Spectral Structure of Cosmic-Ray Electrons+Positrons in the TeV Region with CALET on the International Space Station

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Physical Review Letters 2023年第19期131卷 191001-191001页

作者： O. Adriani Y. Akaike K. Asano Y. Asaoka E. Berti G. Bigongiari W. R. Binns M. Bongi P. Brogi A. Bruno J. H. Buckley N. Cannady G. Castellini C. Checchia M. L. Cherry G. Collazuol G. A. de Nolfo K. Ebisawa A. W. Ficklin H. Fuke S. Gonzi T. G. Guzik T. Hams K. Hibino M. Ichimura K. Ioka W. Ishizaki M. H. Israel K. Kasahara J. Kataoka R. Kataoka Y. Katayose C. Kato N. Kawanaka Y. Kawakubo K. Kobayashi K. Kohri H. S. Krawczynski J. F. Krizmanic P. Maestro P. S. Marrocchesi A. M. Messineo J. W. Mitchell S. Miyake A. A. Moiseev M. Mori N. Mori H. M. Motz K. Munakata S. Nakahira J. Nishimura S. Okuno J. F. Ormes S. Ozawa L. Pacini P. Papini B. F. Rauch S. B. Ricciarini K. Sakai T. Sakamoto M. Sasaki Y. Shimizu A. Shiomi P. Spillantini F. Stolzi S. Sugita A. Sulaj M. Takita T. Tamura T. Terasawa S. Torii Y. Tsunesada Y. Uchihori E. Vannuccini J. P. Wefel K. Yamaoka S. Yanagita A. Yoshida K. Yoshida W. V. Zober Department of Physics University of Florence Via Sansone 1–50019 Sesto Fiorentino Italy INFN Sezione di Florence Via Sansone 1–50019 Sesto Fiorentino Italy Waseda Research Institute for Science and Engineering Waseda University 17 Kikuicho Shinjuku Tokyo 162-0044 Japan JEM Utilization Center Human Spaceflight Technology Directorate Japan Aerospace Exploration Agency 2-1-1 Sengen Tsukuba Ibaraki 305-8505 Japan Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwa-no-Ha Kashiwa Chiba 277-8582 Japan Institute of Applied Physics (IFAC) National Research Council (CNR) Via Madonna del Piano 10 50019 Sesto Fiorentino Italy Department of Physical Sciences Earth and Environment University of Siena via Roma 56 53100 Siena Italy INFN Sezione di Pisa Polo Fibonacci Largo B. Pontecorvo 3–56127 Pisa Italy Department of Physics and McDonnell Center for the Space Sciences Washington University One Brookings Drive St. Louis Missouri 63130-4899 USA Heliospheric Physics Laboratory NASA/GSFC Greenbelt Maryland 20771 USA Center for Space Sciences and Technology University of Maryland Baltimore County 1000 Hilltop Circle Baltimore Maryland 21250 USA Astroparticle Physics Laboratory NASA/GSFC Greenbelt Maryland 20771 USA Center for Research and Exploration in Space Sciences and Technology NASA/GSFC Greenbelt Maryland 20771 USA Department of Physics and Astronomy Louisiana State University 202 Nicholson Hall Baton Rouge Louisiana 70803 USA Department of Physics and Astronomy University of Padova Via Marzolo 8 35131 Padova Italy INFN Sezione di Padova Via Marzolo 8 35131 Padova Italy Institute of Space and Astronautical Science Japan Aerospace Exploration Agency 3-1-1 Yoshinodai Chuo Sagamihara Kanagawa 252-5210 Japan Kanagawa University 3-27-1 Rokkakubashi Kanagawa Yokohama Kanagawa 221-8686 Japan Faculty of Science and Technology Graduate School of Science and Technology Hirosaki University 3 Bunkyo Hirosaki Aomori 036-8561

Detailed measurements of the spectral structure of cosmic-ray electrons and positrons from 10.6 GeV to 7.5 TeV are presented from over 7 years of observations with the CALorimetric Electron Telescope (CALET) on the International Space Station. The instrument, consisting of a charge detector, an imaging calorimeter, and a total absorption calorimeter with a total depth of 30 radiation lengths at normal incidence and a fine shower imaging capability, is optimized to measure the all-electron spectrum well into the TeV region. Because of the excellent energy resolution (a few percent above 10 GeV) and the outstanding e/p separation (105), CALET provides optimal performance for a detailed search of structures in the energy spectrum. The analysis uses data up to the end of 2022, and the statistics of observed electron candidates has increased more than 3 times since the last publication in 2018. By adopting an updated boosted decision tree analysis, a sufficient proton rejection power up to 7.5 TeV is achieved, with a residual proton contamination less than 10%. The observed energy spectrum becomes gradually harder in the lower energy region from around 30 GeV, consistently with AMS-02, but from 300 to 600 GeV it is considerably softer than the spectra measured by DAMPE and Fermi-LAT. At high energies, the spectrum presents a sharp break around 1 TeV, with a spectral index change from −3.15 to −3.91, and a broken power law fitting the data in the energy range from 30 GeV to 4.8 TeV better than a single power law with 6.9 sigma significance, which is compatible with the DAMPE results. The break is consistent with the expected effects of radiation loss during the propagation from distant sources (except the highest energy bin). We have fitted the spectrum with a model consistent with the positron flux measured by AMS-02 below 1 TeV and interpreted the electron+positron spectrum with possible contributions from pulsars and nearby sources. Above 4.8 TeV, a possible contributi

关键词： Cosmic ray acceleration Cosmic ray composition & spectra Cosmic ray propagation Cosmic ray sources Cosmic rays & astroparticles

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Recoil imaging for dark matter, neutrinos, and physics beyond the Standard Model

arXiv

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arXiv 2022年

作者： O'Hare, Ciaran A.J. Loomba, D. Altenmüller, K. Álvarez-Pol, H. Amaro, F.D. Araújo, H.M. Aristizabal Sierra, D. Asaadi, J. Attié, D. Aune, S. Awe, C. Ayyad, Y. Baracchini, E. Barbeau, P. Battat, J.B.R. Bell, N.F. Biasuzzi, B. Bignell, L.J. Boehm, C. Bolognino, I. Brunbauer, F.M. Caamaño, M. Cabo, C. Caratelli, D. Carmona, J.M. Castel, J.F. Cebrián, S. Cogollos, C. Collison, D. Costa, E. Dafni, T. Dastgiri, F. Deaconu, C. De Romeri, V. Desch, K. Dho, G. Di Giambattista, F. Díez-Ibáñez, D. D'Imperio, G. Dutta, B. Eldridge, C. Elliott, S.R. Ezeribe, A.C. Fava, A. Felkl, T. Fernández-Domínguez, B. Ferrer Ribas, E. Flöthner, K.J. Froehlich, M. Galán, J. Galindo, J. García, F. García Pascual, J.A. Gelli, B.P. Ghrear, M. Giomataris, Y. Gnanvo, K. Gramellini, E. Di Cortona, G. Grilli Hall-Wilton, R. Harton, J. Hedges, S. Higashino, S. Hill, G. Holanda, P.C. Ikeda, T. Irastorza, I.G. Jackson, P. Janssens, D. Jones, B. Kaminski, J. Katsioulas, I. Kelly, K. Kemmerich, N. Kemp, E. Korandla, H.B. Kraus, H. Lackner, A. Lane, G.J. Lewis, P.M. Lisowska, M. Luzón, G. Lynch, W.A. Maccarrone, G. Mack, K.J. Majewski, P.A. Mano, R.D.P. Margalejo, C. Markoff, D. Marley, T. Marques, D.J.G. Massarczyk, R. Mazzitelli, G. McCabe, C. McKie, L.J. McLean, A.G. McNamara, P.C. Mei, Y. Messina, A. Mills, A.F. Mirallas, H. Miuchi, K. Monteiro, C.M.B. Mosbech, M.R. Muller, H. Nakamura, K.D. da Luz, H. Natal Natochii, A. Neep, T. Newstead, J.L. Nikolopoulos, K. Obis, L. Oliveri, E. Orlandini, G. de Solórzano, A. Ortiz von Oy, J. Papaevangelou, T. Pérez, O. Perez-Gonzalez, Y.F. Pfeiffer, D. Phan, N.S. Piacentini, S. Picatoste Olloqui, E. Pinci, D. Popescu, S. Prajapati, A. Queiroz, F.S. Raaf, J.L. Resnati, F. Ropelewski, L. Roque, R.C. Ruiz-Choliz, E. Rusu, A. Ruz, J. Samarati, J. Santos, E.M. dos Santos, J.M.F. Sauli, F. Scharenberg, L. Schiffer, T. Schmidt, S. Scholberg, K. Schott, M. Schueler, J. Segui, L. Sekiya, H. Sengupta, D. Slavkovska, Z. Snowden-Ifft, D. The University of Sydney School of Physics NSW2006 Australia ARC Centre of Excellence for Dark Matter Particle Physics Sydney Australia Department of Physics and Astronomy University of New Mexico NM87131 United States Universidad de Zaragoza Zaragoza50009 Spain Instituto Galego de Física de Altas Enerxías University of Santiago de Compostela Santiago de CompostelaE-15782 Spain LIBPhys Department of Physics University of Coimbra Coimbra3004-516 Portugal Department of Physics Blackett Laboratory Imperial College London LondonSW7 2BW United Kingdom Universidad Tecnica Federico Santa Maria Departamento de Fisica Casilla 110-V Valparaiso Chile IFPA Dep. AGO Universite de Liege Liege 1 Belgium University of Texas ArlingtonTX76019 United States IRFU CEA Université Paris-Saclay Gif-sur-YvetteF-91191 France Department of Physics Duke University DurhamNC27708 United States Triangle Universities Nuclear Laboratory DurhamNC27708 United States Istituto Nazionale di Fisica Nucleare Laboratori Nazionali di Frascati I-00040 Italy Istituto Nazionale di Fisica Nucleare Sezione di Roma I-00185 Italy Department of Astroparticle Physics Gran Sasso Science Institute L'AquilaI-67100 Italy Department of Physics Wellesley College WellesleyMA02481 United States ARC Centre of Excellence for Dark Matter Particle Physics School of Physics The University of Melbourne VIC3010 Australia ARC Centre of Excellence for Dark Matter Particle Physics Research School of Physics Australian National University ACT2601 Australia ARC Centre of Excellence for Dark Matter Particle Physics Department of Physics University of Adelaide SA5005 Australia Geneva 231211 Switzerland Fermi National Accelerator Laboratory BataviaIL60510 United States Institut de Ciències del Cosmos Universitat de Barcelona Barcelona Spain INAF Istituto di Astrofisica e Planetologia Spaziali Via del Fosso del Cavaliere 100 Roma00133 Italy Department of Physics Enrico Fermi Inst. Kavli

Recoil imaging entails the detection of spatially resolved ionization tracks generated by particle interactions. This is a highly sought-after capability in many classes of detector, with broad applications across particle and astroparticle physics. However, at low energies, where ionization signatures are small in size, recoil imaging only seems to be a practical goal for micro-pattern gas detectors. This white paper outlines the physics case for recoil imaging, and puts forward a decadal plan to advance towards the directional detection of low-energy recoils with sensitivity and resolution close to fundamental performance limits. The science case covered includes: the discovery of dark matter into the neutrino fog, directional detection of sub-MeV solar neutrinos, the precision study of coherent-elastic neutrino-nucleus scattering, the detection of solar axions, the measurement of the Migdal effect, X-ray polarimetry, and several other applied physics goals. We also outline the R&D programs necessary to test concepts that are crucial to advance detector performance towards their fundamental limit: single primary electron sensitivity with full 3D spatial resolution at the ∼100 micron-scale. These advancements include: the use of negative ion drift, electron counting with high-definition electronic readout, time projection chambers with optical readout, and the possibility for nuclear recoil tracking in high-density gases such as argon. We also discuss the readout and electronics systems needed to scale-up detectors to the ton-scale and beyond. Copyright © 2022, The Authors. All rights reserved.

关键词： Galaxies

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Multi-wavelength analysis of the galactic PeVatron candidate LHAASO J2108+5157

arXiv

引用

arXiv 2023年

作者： Pirola, G. Juryšek, J. Balbo, M. Eckert, D. Tramacere, A. Walter, R. Abe, K. Abe, S. Aguasca-Cabot, A. Agudo, I. Crespo, N. Alvarez Antonelli, L.A. Aramo, C. Arbet-Engels, A. Arcaro, C. Artero, M. Asano, K. Aubert, P. Baktash, A. Bamba, A. Larriva, A. Baquero Baroncelli, L. de Almeida, U. Barres Barrio, J.A. Batkovic, I. Baxter, J. González, J. Becerra Bernardini, E. Bernardos, M.I. Medrano, J. Bernete Berti, A. Bhattacharjee, P. Biederbeck, N. Bigongiari, C. Bissaldi, E. Blanch, O. Bonnoli, G. Bordas, P. Bulgarelli, A. Burelli, I. Burmistrov, L. Buscemi, M. Cardillo, M. Caroff, S. Carosi, A. Carrasco, M.S. Cassol, F. Cauz, D. Cerasole, D. Ceribella, G. Chai, Y. Cheng, K. Chiavassa, A. Chikawa, M. Chytka, L. Cifuentes, A. Contreras, J.L. Cortina, J. Costantini, H. Dalchenko, M. Dazzi, F. De Angelis, A. de Bony de Lavergne, M. De Lotto, B. De Lucia, M. de Menezes, R. Del Peral, L. Deleglise, G. Delgado, C. Mengual, J. Delgado della Volpe, D. Dellaiera, M. Di Piano, A. Di Pierro, F. Di Pilato, A. Di Tria, R. Di Venere, L. Díaz, C. Dominik, R.M. Prester, D. Dominis Donini, A. Dorner, D. Doro, M. Eisenberger, L. Elsässer, D. Emery, G. Escudero, J. Ramazani, V. Fallah Ferrara, G. Ferrarotto, F. Fiasson, A. Foffano, L. Coromina, L. Freixas Fröse, S. Fukami, S. Fukazawa, Y. Garcia, E. López, R. Garcia Gasbarra, C. Gasparrini, D. Geyer, D. Paiva, J. Giesbrecht Giglietto, N. Giordano, F. Gliwny, P. Godinovic, N. Grau, R. Green, J. Green, D. Gunji, S. Günther, P. Hackfeld, J. Hadasch, D. Hahn, A. Hashiyama, K. Hassan, T. Hayashi, K. Heckmann, L. Heller, M. Llorente, J. Herrera Hirotani, K. Hoffmann, D. Horns, D. Houles, J. Hrabovsky, M. Hrupec, D. Hui, D. Hütten, M. Iarlori, M. Imazawa, R. Inada, T. Inome, Y. Ioka, K. Iori, M. Ishio, K. Martinez, I. Jimenez Jurysek, J. Kagaya, M. Karas, V. Katagiri, H. Kataoka, J. Kerszberg, D. Kobayashi, Y. Kohri, K. Kong, A. Kubo, H. Kushida, J. Lainez, M. Lamanna, G. Lamastra, A. Le Flour, T. Linhoff, M. Longo, F. López-Coto, R. Max-Planck-Institut für Physik Föhringer Ring 6 München80805 Germany FZU - Institute of Physics the Czech Academy of Sciences Na Slovance 1999/2 182 00 Prague 8 Czech Republic Department of Astronomy University of Geneva Chemin d’Ecogia 16 VersoixCH-1290 Switzerland Department of Physics Tokai University Japan Institute for Cosmic Ray Research University of Tokyo Japan Departament de Física Quàntica i Astrofísica Institut de Ciències del Cosmos Universitat de Barcelona IEEC-UB Spain Instituto de Astrofísica de Andalucía-CSIC Spain EMFTEL department IPARCOS Universidad Complutense de Madrid Spain INAF - Osservatorio Astronomico di Roma Italy INFN Sezione di Napoli Italy Max-Planck-Institut für Physik Germany INFN Sezione di Padova Università degli Studi di Padova Italy The Barcelona Institute of Science and Technology Spain LAPP Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS-IN2P3 Annecy France Universität Hamburg Institut für Experimentalphysik Germany Graduate School of Science University of Tokyo Japan Universidad del Azuay Ecuador INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna Italy Centro Brasileiro de Pesquisas Físicas Brazil Instituto de Astrofísica de Canarias Departamento de Astrofísica Universidad de La Laguna Spain CIEMAT Spain Department of Physics TU Dortmund University Germany INFN Sezione di Bari Politecnico di Bari Italy INAF - Osservatorio Astronomico di Brera Italy INFN Sezione di Trieste Università degli Studi di Udine Italy University of Geneva Département de physique nucléaire et corpusculaire Switzerland INFN Sezione di Catania Italy Italy Aix Marseille Univ CNRS IN2P3 CPPM France INFN Sezione di Bari Università di Bari Italy INFN Sezione di Torino Italy Palacky University Olomouc Faculty of Science Czech Republic University of Alcalá UAH Spain Port d’Informació Científica Spain University of Rijeka Department of Physics Croatia Institute for Theoretical Physics and Astrophysics Universität Wür

LHAASO J2108+5157 is a recently discovered source, detected in the Ultra-High-Energy band by the LHAASO collaboration. Two molecular clouds were identified in the direction coincident with LHAASO J2108+5157 and, from the spectra reported by LHAASO, there is no sign of an energy cutoff up to 200 TeV. This source makes a promising galactic PeVatron candidate. In 2021, the Large-Sized Telescope prototype (LST-1) of the Cherenkov Telescope Array (CTA) Observatory, collected about 50 hours of quality-selected data on LHAASO J2108+5157. Through these observations, we managed to compute stringent upper limits on the source emission in the multi-TeV band. Together with the analysis of XMM-Newton data and 12 years of Fermi-LAT data, we performed a multi-wavelength study of the source, investigating different possible scenarios of particle acceleration. In this contribution, we will present the results of the analysis, as well as the multi-wavelength modeling, and consequent interpretation of different possible scenarios of emission. © 2023, CC0.

关键词： Telescopes

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Thermal Hall Effects of Spins and Phonons in Kagome Antiferromagnet Cd-Kapellasite

引用

Physical Review X 2020年第4期10卷 041059-041059页

作者： Masatoshi Akazawa Masaaki Shimozawa Shunichiro Kittaka Toshiro Sakakibara Ryutaro Okuma Zenji Hiroi Hyun-Yong Lee Naoki Kawashima Jung Hoon Han Minoru Yamashita The Institute for Solid State Physics The University of Tokyo Kashiwa 277-8581 Japan Graduate School of Engineering Science Osaka University Toyonaka 560-8531 Japan Department of Physics Chuo University Kasuga Bunkyo-ku Tokyo 112-8551 Japan Okinawa Institute of Science and Technology Graduate University Kunigami-gun 904-0495 Japan Department of Applied Physics Graduate School Korea University Sejong 30019 Korea Division of Display and Semiconductor Physics Korea University Sejong 30019 Korea Interdisciplinary Program in E·ICT-Culture-Sports Convergence Korea University Sejong 30019 Korea Department of Physics Sungkyunkwan University Suwon 16419 Korea

We investigate the thermal-transport properties of the kagome antiferromagnet Cd-kapellasite (Cd-K). We find that a field-suppression effect on the longitudinal thermal conductivity κxx sets in below approximately 25 K. This field-suppression effect at 15 T becomes as large as 80% at low temperatures, suggesting a large spin contribution κxxsp in κxx. We also find clear thermal Hall signals in the spin liquid phase in all Cd-K samples. The magnitude of the thermal Hall conductivity κxy shows a significant dependence on the sample’s scattering time, as seen in the rise of the peak κxy value in almost linear fashion with the magnitude of κxx. On the other hand, the temperature dependence of κxy is similar in all Cd-K samples; κxy shows a peak at almost the same temperature of the peak of the phonon thermal conductivity κxxph which is estimated by κxx at 15 T. These results indicate the presence of a dominant phonon thermal Hall κxyph at 15 T. In addition to κxyph, we find that the field dependence of κxy at low fields turns out to be nonlinear at low temperatures, concomitantly with the appearance of the field suppression of κxx, indicating the presence of a spin thermal Hall κxysp at low fields. Remarkably, by assembling the κxx dependence of κxysp data of other kagome antiferromagnets, we find that, whereas κxysp stays a constant in the low-κxx region, κxysp starts to increase as κxx does in the high-κxx region. This κxx dependence of κxysp indicates the presence of both intrinsic and extrinsic mechanisms in the spin thermal Hall effect in kagome antiferromagnets. Furthermore, both κxyph and κxysp disappear in the antiferromagnetic ordered phase at low fields, showing that phonons alone do not exhibit the thermal Hall effect. A high field above approximately 7 T induces κxyph, concomitantly with a field-induced increase of κxx and the specific heat, suggesting a coupling of the phonons to the field-induced spin excitations as the origin of κxyph.

关键词： Frustrated magnetism Spin liquid Thermal Hall effect Thermal conductivity

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