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Timing and Spectral Analysis of HMXB 4U 1700-37 Observed with Insight-HXMT

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arXiv 2023年

作者： Xiao, Hua Ji, Long Zhang, Peng Ducci, Lorenzo Doroshenko, Victor Santangelo, Andrea Zhang, Shu Zhang, Shuang-Nan School of Physics and Astronomy Sun Yat-sen University Zhuhai519082 China College of Science China Three Gorges University Yichang443002 China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle Physics Eberhard Karls Universität Sand 1 TübingenD-72076 Germany ISDC Data Center for Astrophysics Université de Genève 16 chemin d'Écogia Versoix1290 Switzerland INAF - Osservatorio Astronomico di Brera via Bianchi 46 LC Merate23807 Italy Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences 19B Yuquan Road Beijing100049 China

We report timing and spectral studies of the high-mass X-ray binary 4U 1700-37 using InsightHXMT observations carried out in 2020 during its out-of-eclipse state. We found significant variations in flux on a time-scale of kilo-seconds, while the hardness (count rate ratio between 10-30 keV and 2-10 keV) remains relatively stable. No evident pulsations were found over a frequency range of 10−3-2000 Hz. During the spectral analysis, for the first time we took the configuration of different InsightHXMT detectors' orientations into account, which allows us obtaining reliable results even if a stable contamination exists in the field-of-view. We found that the spectrum could be well described by some phenomenological models that commonly used in accreting pulsars (e.g., a power law with a high energy cutoff) in the energy range of 2-100 keV. We found hints of cyclotron absorption features around ∼ 16 keV or/and ∼ 50 keV. Copyright © 2023, The Authors. All rights reserved.

关键词： Spectrum analysis

Four-dimensional differential equations for the leading divergences of dimensionally-regulated loop integrals

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arXiv 2022年

作者： Henn, Johannes Ma, Rourou Yan, Kai Zhang, Yang Max-Planck-Institut für Physik Werner-Heisenberg-Institut MünchenD-80805 Germany Interdisciplinary Center for Theoretical Study University of Science and Technology of China Anhui Hefei230026 China Peng Huanwu Center for Fundamental Theory Anhui Hefei230026 China INPAC Shanghai Key Laboratory for Particle Physics and Cosmology School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China Shanghai200240 China

We invent an automated method for computing the divergent part of Feynman integrals in dimensional regularization. Our method exploits simplifications from four-dimensional integration-by-parts identities. Leveraging algorithms from the literature, we show how to find simple differential equations for the divergent part of Feynman integrals that are free of subdivergences. We illustrate the method by an application to heavy quark effective theory at three loops. Copyright © 2022, The Authors. All rights reserved.

关键词： Differential equations

Confining Strings and the Worldsheet Axion from the Lattice

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arXiv 2024年

作者： Athenodorou, Andreas Dubovsky, Sergei Luo, Conghuan Teper, Michael Computation-based Science and Technology Research Center The Cyprus Institute Cyprus Dipartimento di Fisica Universitá di Pisa INFN Sezione di Pisa Largo Pontecorvo 3 Pisa56127 Italy Center for Cosmology and Particle Physics Department of Physics New York University New YorkNY10003 United States Institute for Advanced Study PrincetonNJ08540 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States Rudolf Peierls Centre for Theoretical Physics Clarendon Laboratory University of Oxford Parks Road OxfordOX1 3PU United Kingdom All Souls College University of Oxford High Street OxfordOX1 4AL United Kingdom

We present a major update on the spectrum of closed flux tubes in D = 3 + 1 SU(N) gauge theories. We measure the excitation spectrum of confining strings wound around a spatial dimension of a size R. We do so for the SU(N) Yang-Mills theory with N = 3,5,6 and for two different values of the lattice spacing. We employ the generalized eigenvalue problem in combination with an extended basis of operators;this enables us to project onto all possible irreducible representations characterised by spin |Jmodulo 4|, transverse parity P, longitudinal parity P as well as by longitudinal momentum p = 2Rπq, and extract accurate results for approximately 35 lightest states. Applying the Thermodynamic Bethe Ansatz (TBA) technique for calculating the finite volume spectrum, we confirm that the observed states are well described by the low energy effective theory of a long string consisting of two translational Goldstone bosons ("phonons"), along with a massive pseudoscalar ("the worldsheet axion") coupled to phonons through a θ-term. Moreover, we find that the leading axion-axion and axion-phonon interactions are well approximated by the TT¯ deformation of a free axion. © 2024, CC BY.

关键词： Phonons

Primordial black holes and induced gravitational waves from inflation in the Horndeski theory of gravity

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arXiv 2021年

作者： Chen, Pisin Koh, Seoktae Tumurtushaa, Gansukh Leung Center for Cosmology and Particle Astrophysics National Taiwan University Taipei10617 Taiwan Department of Physics Center for Theoretical Sciences National Taiwan University Taipei10617 Taiwan Kavli Institute for Particle Astrophysics and Cosmology SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States Department of Science Education Jeju National University Jeju63243 Korea Republic of

We investigate the production of primordial black holes (PBHs) and scalar-induced gravitational waves (GWs) for cosmological models in the Horndeski theory of gravity. The cosmological models of our interest incorporate the derivative self-interaction of the scalar field and the kinetic coupling between the scalar field and gravity. We show that the scalar power spectrum of the primordial fluctuations can be enhanced on small scales due to these additional interactions. Thus, the formation of PBHs and the production of induced GWs are feasible for our model. Parameterizing the scalar power spectrum with a local Gaussian peak, we first estimate the abundance of PBHs and the energy spectrum of GWs produced in the radiation-dominated era. Then, to explain the small-scale enhancement in the power spectrum, we reconstruct the inflaton potential and self-coupling functions from the power spectrum and their spectral tilt. Our results show that the small-scale enhancement in the power spectrum can be explained by the local feature, either a peak or dip, in the self-coupling function rather than the local feature in the inflaton potential. Copyright © 2021, The Authors. All rights reserved.

关键词： Power spectrum

Constraints on axionlike polarization oscillations in the cosmic microwave background with POLARBEAR

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Physical Review D 2023年第4期108卷 043017-043017页

作者： Shunsuke Adachi Tylor Adkins Kam Arnold Carlo Baccigalupi Darcy Barron Kolen Cheung Yuji Chinone Kevin T. Crowley Josquin Errard Giulio Fabbian Chang Feng Raphael Flauger Takuro Fujino Daniel Green Masaya Hasegawa Masashi Hazumi Daisuke Kaneko Nobuhiko Katayama Brian Keating Akito Kusaka Adrian T. Lee Yuto Minami Haruki Nishino Christian L. Reichardt Praween Siritanasak Jacob Spisak Osamu Tajima Satoru Takakura Sayuri Takatori Grant Paul Teply Kyohei Yamada Hakubi Center for Advanced Research Kyoto University Kyoto 606-8501 Japan Department of Physics Faculty of Science Kyoto University Kyoto 606-8502 Japan Department of Physics University of California Berkeley Berkeley California 94720 USA Department of Physics University of California San Diego La Jolla California 92093 USA Astrophysics and Cosmology The International School for Advanced Studies (SISSA) Trieste 34136 Italy Astrophysics and Cosmology Institute for Fundamental Physics of the Universe (IFPU) Trieste 34151 Italy Astrophysics and Cosmology The National Institute for Nuclear Physics (INFN) Trieste 34127 Italy Department of Physics and Astronomy University of New Mexico Albuquerque New Mexico 87131 USA Space Sciences Laboratory University of California Berkeley Berkeley California 94720 USA Computational Cosmology Center Lawrence Berkeley National Laboratory Berkeley California 94720 USA QUP (WPI) KEK Tsukuba Ibaraki 305-0801 Japan Kavli Institute for the Physics and Mathematics of the Universe (WPI) UTIAS The University of Tokyo Kashiwa Chiba 277-8583 Japan Université de Paris Cité CNRS Astroparticule et Cosmologie F-75013 Paris France Center for Computational Astrophysics Flatiron Institute New York New York 10003 USA School of Physics and Astronomy Cardiff University Cardiff CF24 3AA United Kingdom Department of Astronomy School of Physical Sciences University of Science and Technology of China Hefei 230026 China Graduate School of Engineering Science Yokohama National University Yokohama 240-8501 Japan Institute of Particle and Nuclear Studies (IPNS) High Energy Accelerator Research Organization (KEK) Tsukuba 305-0801 Japan SOKENDAI SOKENDAI Tsukuba 305-0801 Japan Institute of Space and Astronautical Science (ISAS) Japan Aerospace Exploration Agency (JAXA) Sagamihara 252-5210 Japan Physics Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA Department of Physics The University of Tokyo Tokyo 113

Very light pseudoscalar fields, often referred to as axions, are compelling dark matter candidates and can potentially be detected through their coupling to the electromagnetic field. Recently a novel detection technique using the cosmic microwave background (CMB) was proposed, which relies on the fact that the axion field oscillates at a frequency equal to its mass in appropriate units, leading to a time-dependent birefringence. For appropriate oscillation periods this allows the axion field at the telescope to be detected via the induced sinusoidal oscillation of the CMB linear polarization. We search for this effect in two years of POLARBEAR data. We do not detect a signal, and place a median 95% upper limit of 0.65° on the sinusoid amplitude for oscillation frequencies between 0.02 days−1 and 0.45 days−1, which corresponds to axion masses between 9.6×10−22 eV and 2.2×10−20 eV. Under the assumptions that (1) the axion constitutes all the dark matter and (2) the axion field amplitude is a Rayleigh-distributed stochastic variable, this translates to a limit on the axion-photon coupling gϕγ<2.4×10−11 GeV−1×(mϕ/10−21 eV).

关键词： Cosmic microwave background cosmology Dark matter particle astrophysics particle dark matter Axions

The Aemulus Project VI: Emulation of beyond-standard galaxy clustering statistics to improve cosmological constraints

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arXiv 2022年

作者： Storey-Fisher, Kate Tinker, Jeremy L. Zhai, Zhongxu DeRose, Joseph Wechsler, Risa H. Banerjee, Arka Center for Cosmology and Particle Physics Department of Physics New York University 726 Broadway New YorkNY10003 United States Department of Astronomy School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai200240 China Waterloo Center for Astrophysics University of Waterloo WaterlooONN2L 3G1 Canada Department of Physics and Astronomy University of Waterloo WaterlooONN2L 3G1 Canada Lawrence Berkeley National Laboratory 1 Cyclotron Road BerkeleyCA94720 United States Kavli Institute for Particle Astrophysics and Cosmology Department of Physics Stanford University StanfordCA94305 United States SLAC National Accelerator Laboratory Menlo ParkCA94025 United States Department of Physics Stanford University 382 Via Pueblo Mall StanfordCA94305 United States Department of Physics Indian Institute of Science Education and Research Homi Bhabha Road Pashan Pune411008 India

There is untapped cosmological information in galaxy redshift surveys in the nonlinear regime. In this work, we use the Aemulus suite of cosmological N-body simulations to construct Gaussian process emulators of galaxy clustering statistics at small scales (0.1-50 h−1 Mpc) in order to constrain cosmological and galaxy bias parameters. In addition to standard statistics-the projected correlation function wp(rp), the redshift-space monopole of the correlation function ξ0(s), and the quadrupole ξ2(s)-we emulate statistics that include information about the local environment, namely the underdensity probability function PU(s) and the density-marked correlation function M(s). This extends the model of Aemulus III for redshift-space distortions by including new statistics sensitive to galaxy assembly bias. In recovery tests, we find that the beyond-standard statistics significantly increase the constraining power on cosmological parameters of interest: including PU(s) and M(s) improves the precision of our constraints on Ωm by 27%, σ8 by 19%, and the growth of structure parameter, fσ8, by 12% compared to standard statistics. We additionally find that scales below ∼6 h−1 Mpc contain as much information as larger scales. The density-sensitive statistics also contribute to constraining halo occupation distribution parameters and a flexible environment-dependent assembly bias model, which is important for extracting the small-scale cosmological information as well as understanding the galaxy-halo connection. This analysis demonstrates the potential of emulating beyond-standard clustering statistics at small scales to constrain the growth of structure as a test of cosmic acceleration. Copyright © 2022, The Authors. All rights reserved.

关键词： Statistics

Scalars are universal: Equivariant machine learning, structured like classical physics

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arXiv 2021年

作者： Villar, Soledad Hogg, David W. Storey-Fisher, Kate Yao, Weichi Blum-Smith, Ben Department of Applied Mathematics and Statistics Johns Hopkins University United States Flatiron Institute A Divison of the Simons Foundation United States Center for Cosmology and Particle Physics Department of Physics New York University United States Department of Technology Operations and Statistics Stern School of Business New York University United States Center for Data Science New York University United States

There has been enormous progress in the last few years in designing neural networks that respect the fundamental symmetries and coordinate freedoms of physical law. Some of these frameworks make use of irreducible representations, some make use of high-order tensor objects, and some apply symmetry-enforcing constraints. Different physical laws obey different combinations of fundamental symmetries, but a large fraction (possibly all) of classical physics is equivariant to translation, rotation, reflection (parity), boost (relativity), and permutations. Here we show that it is simple to parameterize universally approximating polynomial functions that are equivariant under these symmetries, or under the Euclidean, Lorentz, and Poincaré groups, at any dimensionality d. The key observation is that nonlinear O(d)-equivariant (and related-group-equivariant) functions can be universally expressed in terms of a lightweight collection of scalars-scalar products and scalar contractions of the scalar, vector, and tensor inputs. We complement our theory with numerical examples that show that the scalar-based method is simple, efficient, and scalable. Copyright © 2021, The Authors. All rights reserved.

关键词： Tensors

Polarization Reconstruction of Cosmic Rays with the ARIANNA Neutrino Radio Detector 37

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Polarization Reconstruction of Cosmic Rays with the ARIANNA ...

37th International Cosmic Ray Conference, ICRC 2021

作者： Zhao, Leshan Anker, Astrid Baldi, Pierre Barwick, Steven W. Beise, Jakob Bernhoff, Hans Besson, Dave Z. Bingefors, Nils Cataldo, Maddalena Chen, Pisin Fernández, Daniel García Gaswint, Geoffrey Glaser, Christian Hallgren, Allan Hallmann, Steffen Hanson, Jordan C. Klein, Spencer R. Kleinfelder, Stuart A. Lahmann, Robert Liu, Jiayi Magnuson, Mitchell McAleer, Stephen Meyers, Zach Nam, Jiwoo Nelles, Anna Novikov, Alexander Paul, Manuel P. Persichilli, Christopher Plaisier, Ilse Pyras, Lilly Rice-Smith, Ryan Tatar, Joulien Wang, Shih-Hao Welling, Christoph Zhao, Leshan University of California Irvine Irvine United States Department of Physics and Astronomy University of California IrvineCA92697 United States Department of Information and Computer Science University of California IrvineCA92697 United States Uppsala University Department of Physics and Astronomy UppsalaSE-752 37 Sweden Uppsala University Department of Engineering Sciences Division of Electricity UppsalaSE-752 37 Sweden Department of Physics and Astronomy University of Kansas LawrenceKS66045 United States Moscow115409 Russia ECAP Friedrich-Alexander Universität Erlangen-Nürnberg Erlangen91058 Germany Department of Physics Leung Center for Cosmology and Particle Astrophysics National Taiwan University Taipei10617 Taiwan DESY Zeuthen15738 Germany Whittier College Department of Physics WhittierCA90602 United States Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Electrical Engineering and Computer Science University of California IrvineCA92697 United States Research Cyberinfrastructure Center University of California IrvineCA92697 United States

The ARIANNA detector is designed to detect neutrinos of energies above 1016 eV. Due to the similarities in generated radio signals, cosmic rays are often used as test beams for neutrino detectors. Some ARIANNA detector stations are equipped with antennas capable of detecting air showers. The radio emission properties of air showers are well understood, and the polarization of the radio signal can be predicted from arrival direction with high precision. For this reason, cosmic rays can be used as a proxy to assess the reconstruction capabilities of the ARIANNA neutrino detector. We report on dedicated efforts of reconstructing the polarization of cosmic-ray radio pulses. A total of 148 cosmic rays are identified from over 90,000 triggered events collected between Nov 21, 2018 and Mar 15, 2019. A cut was put on these events requiring them to have a signal-to-noise (SNR) ratio of at least 4.5 in all upward-facing channels. This was to improve the performance of arrival direction and polarization reconstruction algorithms. Polarization of these cosmic rays were reconstructed with a resolution of 3.5 degrees (68% containment), which agrees with the expected value we obtained from simulation. Furthermore, if we subselect events with zenith angle greater than 70 deg, the contribution to polarization of Askaryan effect is reduced, which reduces the error in the predicted polarization. With limited statistics, we find the polarization uncertainty is reduced to 1.3 deg (68% containment). © Copyright owned by the author(s).

关键词： Polarization

Dark energy and matter interacting scenario to relieve H_(0) and S_(8) tensions

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Chinese physics C 2024年第5期48卷 1-7页

作者：高立场薛社生张鑫 Key Laboratory of Cosmology and Astrophysics(Liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Kapteyn Astronomical Institute University of GroningenP.O.Box 8009700 AV Groningenthe Netherlands ICRANet Piazzale della Repubblica10-65122PescaraItaly ICTP-AP University of Chinese Academy of SciencesBeijing 100049China Physics Department Sapienza University of RomeP.le A.Moro 500185RomeItaly INFN Sezione di PerugiaVia A.PascoliI-06123PerugiaItaly Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

We consider a new cosmological model(calledΛCDM),in which the vacuum energy interacts with matter and radiation,and test this model using the current cosmological *** the CMB+BAO+SN(CBS)dataset to constrain the model,we find that H_(0) and S_(8) tensions are relieved to 2.87σand 2.77σ,***,in this case,theΛCDM model is not favored by the data,compared withΛ*** find that when the H_(0) and S_(8) data are added to the data combination,the situation is significantly *** the CBS+H_(0) case,the model relieves the H_(0) tension to 0.47σ,and the model is favored overΛ*** the CBS+H_(0)+S_(8) case,we obtain a synthetically best situation,in which the H_(0) and S_(8) tensions are relieved to 0.72σand 2.11σ,*** this case,the model is most favored by the ***,this cosmological model can greatly relieve the H_(0) tension and simultaneously effectively alleviate the S_(8) tension.

关键词： dark energy interacting dark energy model the Hubble constant Hubble tension cosmological constraint