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Elastic Scattering of Cosmological Gravitational Wave Backgrounds: Primordial Black Holes and Stellar Objects

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arXiv 2023年

作者： Howard, Marcell König, Morgane Pittsburgh Particle Physics Astrophysics and Cosmology Center Department of Physics and Astronomy University of Pittsburgh PittsburghPA15260 United States Laboratory of Nuclear Science Center for Theoretical Physics Massachusetts Institute of Technology CambridgeMA02139 United States

Primordial black holes (PBHs) are plausible dark matter candidates that formed from the gravitational collapse of primordial density fluctuations. Current observational constraints allow asteroid-mass PBHs to account for all of the cosmological dark matter. We show that elastic scattering of a cosmological gravitational wave background, these black holes generate spectral distortions on the background of 0.3% for cosmologically relevant frequencies without considering coherent scattering and 5% when the coherent enhancement is included. Scattering from stellar objects induce much smaller distortions. Detectability of this signal depends on our ultimate understanding of the unperturbed background spectrum. Copyright © 2023, The Authors. All rights reserved.

关键词： Gravity waves

Axion cosmology with post-Newtonian corrections

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Physical Review D 2023年第8期107卷 083508-083508页

We present first-order post-Newtonian (1PN) approximations of a general imperfect fluid and of an axion as a coherently oscillating massive scalar field, both in the cosmological context. For the axion, using the Klein transformation and Madelung transformation we derive the Schrödinger and Madelung hydrodynamic formulations, respectively, in an exact covariant way and to 1PN order. Complete sets of equations for the 1PN formulations are derived without fixing the temporal gauge condition. We study the linear instability in cosmology and a static limit for both fluid and axion; these are presented independently of the gauge condition to 1PN order, thus are naturally gauge invariant.

关键词： cosmology

The Dependence of Dark Matter Halo Properties on the Morphology of Their Central Galaxies from Weak Lensing

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arXiv 2024年

作者： Liu, Zhenjie Xu, Kun Zhang, Jun Wang, Wenting Liu, Cong Department of Astronomy Shanghai Jiao Tong University Shanghai200240 China Division of Physics and Astrophysical Science Graduate School of Science Nagoya University Nagoya464-8602 Japan Center for Particle Cosmology Department of Physics and Astronomy University of Pennsylvania PhiladelphiaPA19104 United States Institute for Computational Cosmology Department of Physics Durham University South Road DurhamDH1 3LE United Kingdom Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai200240 China

Xu & Jing (2022) reported a monotonic relationship between host halo mass (Mh) and the morphology of massive central galaxies, characterized by the Sérsic index (n), at fixed stellar mass, suggesting that morphology could serve as a good secondary proxy for halo mass. Since their results were derived using the indirect abundance matching method, we further investigate the connection between halo properties and central galaxy morphology using weak gravitational lensing. We apply galaxy-galaxy lensing to measure the excess surface density around CMASS central galaxies with stellar masses in the range of 11.3 ∗/M☉ h, and observe a possible evidence of the positive correlation of n and halo concentration. After accounting for color, we find that neither color nor morphology alone can determine halo mass, suggesting that a combination of both may serve as a better secondary proxy. In comparison to hydrodynamic simulations, we find that TNG300 produce much weaker correlations between Mh and n. Furthermore, disabling jet-mode active galactic nuclei feedback in SIMBA simulations results in the disappearance of the positive n−Mh relationship, suggesting that the star formation history influenced by black holes may be a contributing factor. Copyright © 2024, The Authors. All rights reserved.

关键词： Dark Matter

Cosmological collider non-Gaussianity from multiple scalars and R2 gravity

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arXiv 2024年

作者： Aoki, Shuntaro Ghoshal, Anish Strumia, Alessandro Particle Theory and Cosmology Group Center for Theoretical Physics of the Universe Institute for Basic Science Daejeon34126 Korea Republic of Institute of Theoretical Physics Faculty of Physics University of Warsaw Poland Dipartimento di Fisica Università di Pisa Pisa Italy

Cosmological collider signals of primordial non-Gaussianity arise at tree level when an extra scalar has Hubble mass during inflation. We critically review the formalism finding that a large class of inflationary theories, based on Planck-scale physics, predict a scalar bi-spectrum around the gravitational floor level. This mild signal arises for example in R2 gravity, in the regime where its gravitational scalar has Hubble-scale mass. Signals much above the gravitational floor arise in theories where scalars undergo multiple turns during inflation, thanks to sub-Planckian physics. Copyright © 2024, The Authors. All rights reserved.

关键词： cosmology

On the renormalization of entanglement entropy

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AAPPS Bulletin 2021年第1期31卷 1-7页

作者： Pang, Jin-Yi Chen, Jiunn-Wei College of Science University of Shanghai for Science and Technology Shanghai 200093 China Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universität Bonn Bonn 53115 Germany Department of Physics Center for Theoretical Physics and Leung Center for Cosmology and Particle Astrophysics National Taiwan University Taipei Taiwan Physics Division National Center for Theoretical Sciences Taipei Taiwan

The renormalization of entanglement entropy of quantum field theories is investigated in the simplest setting with a λ ϕ 4 scalar field theory. The 3+1 dimensional spacetime is separated into two regions by an infini... 详细信息

The renormalization of entanglement entropy of quantum field theories is investigated in the simplest setting with a λ ϕ ⁴ scalar field theory. The 3+1 dimensional spacetime is separated into two regions by an infinitely flat 2-dimensional interface. The entanglement entropy of the system across the interface has an elegant geometrical interpretation using the replica trick, which requires putting the field theory on a curved spacetime background. We demonstrate that the theory, and hence the entanglement entropy, is renormalizable at order λ once all the relevant operators up to dimension 4 are included in the action. This exercise has a one-to-one correspondence to entanglement entropy interpretation of the black hole entropy which suggests that our treatment is sensible. Our study suggests that entanglement entropy is renormalizable and is a physical quantity. © 2021, The Author(s).

关键词： Back hole Entanglement entropy Quantum field theory Renormalization

Suppression of accidental backgrounds with deep neural networks in the PandaX-II experiment

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arXiv 2023年

作者： Shaheed, Nasir Chen, Xun Wang, Meng Research Center for Particle Science and Technology Institute of Frontier and Interdisciplinary Science Shandong University Shandong Qingdao266237 China INPAC School of Physics and Astronomy Shanghai Jiao Tong University MOE Key Lab for Particle Physics Astrophysics and Cosmology Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai200240 China Shanghai Jiao Tong University Sichuan Research Institute Chengdu610213 China

The PandaX dark matter detection project searches for dark matter particles using the technology of dual phase xenon time projection chamber. The low expected rate of the signal events makes the control of backgrounds crucial for the experiment success. In addition to reducing external and internal backgrounds during the construction and operation of the detector, special techniques are employed to suppress the background events during the data analysis. In this article, we demonstrate the use of deep neural networks (DNNs) for suppressing the accidental backgrounds, as an alternative to the boosted-decision-tree method used in previous analysis of PandaX-II. A new data preparation approach is proposed to enhance the stability of the machine learning algorithms to be run and ultimately the sensitivity of the final data analysis. Copyright © 2023, The Authors. All rights reserved.

关键词： Deep neural networks

Optimization of performance of the KM2A full array using the Crab Nebula

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Chinese physics C 2024年第6期48卷 169-178页

作者：曹臻 F.Aharonian 安琪阿西克古白云翔包逸炜 D.Bastieri 毕效军毕玉江蔡金庭曹晴曹文羽曹喆常进常劲帆陈尚明陈恩生陈亮陈林陈龙陈明君陈玛丽陈起辉陈素弘陈天禄陈阳程宁程耀东崔明阳崔树旺崔晓红崔昱东戴本忠代洪亮戴子高单增罗布 D.della Volpe 董绪强段凯凯樊军辉范一中方军方堃冯存峰封莉冯少辉丰晓婷冯有亮 S.Gabici 高博高川东高林青高启高卫高伟康葛茂茂耿利斯 G.Giacinti 龚光华苟全补顾旻皓郭福来郭晓磊郭义庆郭莹莹韩毅昂何会海贺昊宁何佳银何新波何钰 M.Heller 贺远强侯博文侯超侯贤胡红波胡铨胡世聪黄代绘黄天奇黄文俊黄性涛黄晓渊黄勇黄志成季筱璐贾焕玉贾康江琨姜晓巍姜泽军金敏康明铭柯通 D.Kuleshov.K.Kurinov 李兵兵李澄李骢李丹李飞李海波李会财李华阳李军李剑李捷李凯李文龙李文莲李秀荣李昕李一卓李哲黎卓梁恩维梁云峰林苏杰刘冰刘成刘栋刘虎刘海东刘佳刘江来刘金艳刘茂元柳若愚刘四明刘伟刘怡刘以农鲁睿罗晴吕洪魁马伯强马玲玲马欣华毛基荣闵振 W.Mitthumsiri 穆慧君南云程 A.Neronov 区子维庞彬宇 P.Pattarakijwanich 裴致远齐孟尧祁业情乔冰强秦家军 D.Ruffolo A.Sáiz D.Semikoz 邵澄宇邵琅 O.Shchegolev 盛祥东舒富文宋慧超 Yu.V.Stenkin V.Stepanov 苏扬孙秦宁孙晓娜孙志斌谭柏轩唐庆文唐泽波田文武王超王昌贝王广威王洪光王惠惠王建成汪凯王利苹王玲玉王培汉王冉王为王祥高王祥玉王阳王玉东王岩谨王忠海王仲翔王振王铮韦大明魏俊杰魏永健文韬吴超勇吴含荣武莎吴雪峰吴雨生席邵强夏捷夏君集项光漫肖迪泫肖刚辛广广辛玉良邢祎熊峥徐东莲徐仁峰徐仁新徐伟立薛良闫大海颜景志颜田杨朝文杨帆杨冯帆杨何文杨佳盈杨莉莉杨明洁杨睿智杨深邦姚玉华姚志国叶一锰尹丽巧尹娜游晓浩游智勇于艳红袁强岳华曾厚敦曾婷轩曾玮查敏张彬彬张丰张海明张恒英张建立张丽霞张力张鹏飞张佩佩张瑞张少博张少如张寿山张潇张笑鹏张云峰张毅张勇赵兵赵静赵雷赵立志赵世平郑福周斌周浩周佳能周猛周平周荣周勋秀祝成光祝凤荣朱辉朱科军左雄 LHAASO Collaboration Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Tianfu Cosmic Ray Research Center Chengdu 610000China Dublin Institute for Advanced Studies 31 Fitzwilliam Place2 DublinIreland Max-Planck-Institut for Nuclear Physics P.O.Box 10398069029 HeidelbergGermany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Hefei 230026China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Hebei Normal University Shijiazhuang 050024China Key Laboratory of Dark Matter and Space Astronomy&Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000TibetChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Physics and Astronomy(Zhuhai)&School of Physics(Guangzhou)&Sino-French Institute of Nuclear Engineering and Technology(Zhuhai) Sun Yat-sen UniversityZhuhai 519000&Guangzhou 510275China School of Physics and Astronomy Yunnan UniversityKunming 650091China Département de Physique Nucléaire et Corpusculaire Facultéde SciencesUniversitéde Genève24 Quai Ernest Ansermet1211 GenevaSwitzerland Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China APC Universit'e Paris Cit'eCNRS/IN2P3CEA/IRFUObservat

The full array of the Large High Altitude Air Shower Observatory(LHAASO)has been in operation since July *** its kilometer-square array(KM2A),we optimized the selection criteria for very high and ultrahigh energyγ-rays using data collected from August 2021 to August 2022,resulting in an improvement in significance of the detection in the Crab Nebula of approximately 15%,compared with that of previous *** the implementation of these new selection criteria,the angular resolution was also significantly improved by approximately 10%at tens of *** aspects of the full KM2A array performance,such as the pointing error,were also calibrated using the Crab *** resulting energy spectrum of the Crab Nebula in the energy range of 10-1000 TeV are well fitted by a log-parabola model,which is consistent with the previous results from LHAASO and other experiments.

关键词： γ-ray Crab Nebula significance

Supernovae Time Profiles as a Probe of New physics at Neutrino Telescopes

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arXiv 2024年

作者： Lazar, Jeff Li, Ying-Ying Argüelles, Carlos A. Brdar, Vedran Department of Physics Laboratory for Particle Physics and Cosmology Harvard University CambridgeMA02138 United States Department of Physics Wisconsin IceCube Particle Astrophysics Center University of Wisconsin-Madison MadisonWI53706 United States Peng Huanwu Center for Fundamental Theory Anhui Hefei230026 China Interdisciplinary Center for Theoretical Study University of Science and Technology of China Anhui Hefei230026 China Department of Physics Oklahoma State University StillwaterOK74078 United States

Neutrino telescopes, including IceCube, can detect galactic supernova events by observing the collective rise in photomultiplier count rates with a sub-second time resolution. Leveraging precise timing, we demonstrate the ability of neutrino telescopes to explore new weakly coupled states emitted from supernovae and subsequently decaying to neutrinos. Our approach utilizes publicly available packages, ASTERIA and SNEWPY, for simulating detector responses and parametrizing neutrino fluxes originating from Standard Model and new physics. We present results for two beyond the Standard Model scenarios and introduce the tool developed for testing a diverse range of new physics models. © 2024, CC BY.

关键词： Supernovae

Black Hole Complementarity and ER/EPR

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arXiv 2025年

作者： Bao, Ning Remmen, Grant N. Department of Physics Northeastern University BostonMA02115 United States Computational Science Initiative Brookhaven National Laboratory UptonNY11973 United States Center for Cosmology and Particle Physics Department of Physics New York University New YorkNY10003 United States

We demonstrate that wormholes must be entangled regardless of asymptotic boundary conditions. Assuming black hole complementarity, we argue that traversable wormholes instantiate entanglement-assisted quantum channels and that this entanglement must be present between the stretched horizons as an initial condition prior to traversability. This result demonstrates the forward direction of the ER/EPR conjectures. © 2025, CC BY.

关键词： Quantum channel