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Upper Bound on Thermal Gravitational Wave Backgrounds from Hidden Sectors

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arXiv 2023年

作者： Drewes, Marco Georis, Yannis Klaric, Juraj Klose, Philipp Centre for Cosmology Particle Physics and Phenomenology Université Catholique de Louvain Louvain-la-NeuveB-1348 Belgium Institute for Theoretical Physics Amsterdam Delta Institute for Theoretical Physics University of Amsterdam Science Park 904 Amsterdam1098 XH Netherlands Nikhef Theory Group Science Park 105 Amsterdam1098 XG Netherlands University of Zagreb Faculty of Science Department of Physics Zagreb10000 Croatia Institute for Theoretical Physics Albert Einstein Center for Fundamental Physics University of Bern Switzerland Fakultät für Physik Universität Bielefeld Germany

Hot viscous plasmas unavoidably emit a gravitational wave background, similar to electromagnetic black body radiation. We study the contribution from hidden particles to the diffuse background emitted by the primordial plasma in the early universe. While this contribution can easily dominate over that from Standard Model particles, we find that both are capped by a generic upper bound that makes them difficult to detect with interferometers in the foreseeable future. We illustrate our results for axion-like particles and heavy neutral leptons. Finally, our results suggest that previous works overestimated the gravitational wave background from particle decays out of thermal equilibrium. Copyright © 2023, The Authors. All rights reserved.

关键词： Gravitational effects

Towards an Effective String Theory for the flux tube

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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 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 University of Oxford Parks Road OxfordOX1 3PU United Kingdom All Souls College University of Oxford High Street OxfordOX1 4AL United Kingdom

The quest to develop an effective string theory capable of describing the confining flux tube has been a longstanding objective within the theoretical physics community. Recent lattice results indicate that the low-lying spectrum of the flux tube in both three and four dimensions can be partially described by the Nambu-Goto string with minor deviations. However, several excitation states exhibit significant corrections that have remained unexplained until recently. Recent advancements suggest that a Thermodynamic Bethe Ansatz (TBA) analysis, expanded in both 1/R√σ and the softness of phonons i.e. p/√σ, can lead to a robust effective string theory for the flux-tube with length R. Furthermore, lattice data points to the existence of an axion field on the world-sheet of the flux-tube, implying that an Axionic String Ansatz (ASA) should accompany the Nambu-Goto framework. We will provide compelling evidence in these proceedings that this approach can closely approximate the flux tube data. We will demonstrate this by comparing results obtained for the spectrum of the closed SU(Nc) flux-tube extracted using lattice techniques in four dimensions. © 2024, CC BY-NC-ND.

关键词： String theory

β-decay half-lives of the r-process waiting-point isotones of N=81 and 82 nuclei

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Physical Review C 2023年第3期107卷 034316-034316页

作者： C. Ma Y. Lu Y. Lei Y. M. Zhao Shanghai Key Laboratory of Particle Physics and Cosmology School of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China College of Physics and Engineering Qufu Normal University Qufu 273165 China School of National Defense Science and Technology Southwest University of Science and Technology Mianyang 621010 China Collaborative Innovation Center of IFSA (CICIFSA) Shanghai Jiao Tong University Shanghai 200240 China

In this paper we perform systematic calculations of β-decay half-lives for the r-process waiting-point isotones of N=81 and 82, in the framework of nucleon-pair approximation. A phenomenological form of the Hamiltonian, which includes single-particle energies, pairing plus quadrupole interactions, and Gamow-Teller interactions is assumed, and the theoretical β-decay energies are taken based on the Bayesian machine learning. A good agreement with experimental values of half-lives is achieved by using the nucleon-pair truncated model space in which the S-pair condensation dominates. Our calculated half-lives are found to be very sensitive to β-decay energies on the one hand, and are quite robust with respect to extension of the model space and variation of interaction parameters on the other hand.

关键词： Beta decay Binding energy & masses Collective levels Energy levels & level densities Shell model 90 ≤ A ≤ 149

A novel integrated Sachs-Wolfe effect from Early Dark Energy

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arXiv 2023年

作者： Smith, Tristan L. Giblin, John T. Amin, Mustafa Gerhardinger, Mary Florio, Ericka Cerep, Matthew Daniels, Shar Department of Physics and Astronomy Swarthmore College SwarthmorePA19081 United States Center for Cosmology and Particle Physics Department of Physics New York University New YorkNY10003 United States Department of Physics Kenyon College 201 N College Rd GambierOH43022 United States Department of Physics Cerca Institute for the Science of Origins Case Western Reserve University ClevelandOH44106-7079 United States Department of Physics and Astronomy Rice University HoustonTX77005 United States Center for Particle Cosmology Department of Physics and Astronomy University of Pennsylvania PhiladelphiaPA19104 United States Department of Mathematics and Theoretical Physics University of Cambridge Wilberforce Rd CambridgeCB3 0WA United Kingdom Department of Physics and Astronomy West Virginia University P.O. Box 6315 MorgantownWV26506 United States Center for Gravitational Waves and Cosmology West Virginia University Chestnut Ridge Research Building MorgantownWV26505 United States Department of Physics and Astronomy University of Delaware NewarkDE19716 United States

We study the nonlinear effects of minimally coupled, massless, cosmological scalar fields on the cosmic microwave background (CMB). These fields can exhibit post-recombination parametric resonance and subsequent nonlinear evolution leading to novel contributions to the gravitational potential. We compute the resulting contributions to the CMB temperature anisotropies through the time-variation of the gravitational potential (i.e., the integrated Sachs-Wolfe (ISW) effect). We find that fields that constitute 5% of the total energy density and become dynamical at zc 104can produce marginally observable ISW signals at multipoles 2000. Fields that become dynamical at earlier times and/or have initial displacements at a flatter part of their potential, produce ISW contributions that are significantly larger and at higher multipoles. We calculate these dynamics and the resulting evolution of gravitational perturbations using analytic estimates alongside detailed nonlinear lattice simulations, which couple scalar fields and cosmological fluids to a perturbed metric. Finally, we discuss the possibility of detecting these features with future high-resolution CMB observations. © 2023, CC BY.

关键词： cosmology

Aemulus $ν$: Precision halo mass functions in w$ν$CDM cosmologies

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arXiv 2024年

作者： Shen, Delon Kokron, Nickolas DeRose, Joseph Tinker, Jeremy Wechsler, Risa H. Banerjee, Arka Department of Physics Stanford University 382 Via Pueblo Mall StanfordCA94305 United States Kavli Institute for Particle Astrophysics and Cosmology SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo ParkCA94025 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States School of Natural Sciences Institute for Advanced Study 1 Einstein Drive PrincetonNJ08540 United States Physics Division Lawrence Berkeley National Laboratory 1 Cyclotron Rd BerkeleyCA United States Center for Cosmology and Particle Physics Department of Physics New York University 726 Broadway New YorkNY10003 United States Department of Physics Indian Institute of Science Education and Research Homi Bhabha Road Pashan Pune411008 India

Precise and accurate predictions of the halo mass function for cluster mass Process Regression, has negligible theoretical uncertainties compared to dominant sources of error in future cluster abundance studies. Our emulator is publicly available, providing the community with a crucial tool for upcoming cosmological surveys such as LSST and Euclid. Copyright © 2024, The Authors. All rights reserved.

关键词： cosmology

Boosting Line Intensity Map Signal-to-Noise with the Ly-α Forest Cross-Correlation

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arXiv 2023年

作者： Qezlou, Mahdi Bird, Simeon Lidz, Adam Sun, Guochao Newman, Andrew B. Rudie, Gwen C. Ni, Yueying Croft, Rupert Di Matteo, Tiziana Department of Physics and Astronomy University of California Riverside 900 University Ave RiversideCA92521 United States The Observatories of the Carnegie Institution for Science 813 Santa Barbara Street PasadenaCA91101 United States Center for Particle Cosmology Department of Physics and Astronomy University of Pennsylvania PhiladelphiaPA19104 United States California Institute of Technology 1200 E. California Blvd. PasadenaCA91125 United States McWilliams Center for Cosmology Department of Physics Carnegie Mellon University PittsburghPA15213 United States Harvard–Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States NSF AI Planning Institute for Physics of the Future Carnegie Mellon University PittsburghPA15213 United States

We forecast the prospects for cross-correlating future line intensity mapping (LIM) surveys with the current and future Ly-α forest measurements. Using large cosmological hydrodynamic simulations, we model the emission from the CO rotational transition in the CO Mapping Array Project LIM experiment at the 5-yr benchmark and the Ly-α forest absorption signal for extended Baryon Acoustic Oscillations (BOSS), Dark energy survey instrument (DESI), and Prime Focus multiplex Spectroscopy survey (PFS). We show that CO × Ly-α forest significantly enhances the detection signal-to-noise ratio (S/N) of CO, with up to 300 per cent improvement when correlated with the PFS Ly-α forest survey and a 50–75 per cent enhancement with the available eBOSS or the upcoming DESI observations. This is competitive with even CO × spectroscopic galaxy surveys. Furthermore, our study suggests that the clustering of CO emission is tightly constrained by CO × Ly-α forest due to the increased sensitivity and the simplicity of Ly-α absorption modelling. Foreground contamination or systematics are expected not to be shared between LIM and Ly-α forest observations, providing an unbiased inference. Ly-α forest will aid in detecting the first LIM signals. We also estimate that [C II] × Ly-α forest measurements from Experiment for Cryogenic Large-Aperture Intensity Mapping and DESI/eBOSS should have a larger S/N than planned [C II] × quasar observations by about an order of magnitude. © 2023, CC BY.

关键词： Galaxies

The 2.5-meter Wide Field Survey Telescope Real-time data Processing Pipeline I: From raw data to alert distribution

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arXiv 2025年

作者： Cai, Minxuan Xu, Zelin Fan, Lulu Wan, Zhen Kong, Xu Hu, Weida Jiang, Ji-An Hu, Lei Zhu, Qing-Feng Li, Guoliang Lin, Jie Fang, Min Xue, Yongquan Zhen, Xianzhong Wang, Tinggui Department of Astronomy University of Science and Technology of China Hefei230026 China School of Astronomy and Space Science University of Science and Technology of China Hefei230026 China Deep Space Exploration Laboratory Hefei230088 China Department of Physics and Astronomy Texas A&M University College StationTX77843-4242 United States George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy Texas A&M University College StationTX77843-4242 United States McWilliams Center for Cosmology Department of Physics Carnegie Mellon University 5000 Forbes Ave PittsburghPA15213 United States Purple Mountain Observatory Chinese Academy of Sciences Nanjing210023 China Institute and Key Laboratory for Particle Physics Astrophysics and Cosmology Ministry of Education Shanghai Jiao Tong University Shanghai201210 China

The Wide Field Survey Telescope (WFST) is a dedicated photometric surveying facility built jointly by the University of science and Technology of China (USTC) and the Purple Mountain Observatory (PMO). Since many of its scientific objectives rely on near-real-time data for effective analysis, prompt processing of WFST images is of great significance. To meet this need, we adapted the Rubin Observatory Legacy Survey of Space and Time (LSST) science pipelines to handle the data collected by WFST. This paper presents the complete data processing workflow, from ingestion of raw images to the distribution of alerts, and details the primary data products generated by our pipeline. Researchers using data processed by this pipeline can refer to this document to fully understand the data processing procedures. © 2025, CC BY-NC-ND.

关键词： data reduction

Probing the sign-changeable interaction between dark energy and dark matter with DESI baryon acoustic oscillations and DES supernovae data

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arXiv 2025年

作者： Li, Tian-Nuo Du, Guo-Hong Li, Yun-He Wu, Peng-Ju Jin, Shang-Jie Zhang, Jing-Fei Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China School of Physics Ningxia University Yinchuan750021 China Department of Physics University of Western Australia PerthWA6009 Australia MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

There is a possibility of interaction between dark energy and dark matter, and this interaction may also undergo a sign change during the evolution of the universe. In this paper, we utilize the latest observational data to constrain models of a sign-changeable interaction. The data we employ, in addition to the cosmic microwave background data, also encompass the first-year baryon acoustic oscillation data from DESI and the type Ia supernova data of the full 5-year observation from DES. To achieve high generality, we investigate four interacting dark energy (IDE) models with different forms of the interaction term Q: (i) IDE1 with Q = β(a)Hρde;(ii) IDE2 with Q = β(a)Hρc;(iii) IDE3 with Q = β(a)H0ρde;(iv) IDE4 with Q = β(a)H0ρc. From the analysis, we observe that β(z) > 0 at early times and β(z) Copyright © 2025, The Authors. All rights reserved.

关键词： Supernovae

Insight-HXMT, NICER and NuSTAR views to the newly discovered black hole X-ray binary Swift J151857.0–572147

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arXiv 2025年

作者： Peng, Jing-Qiang Zhang, Shu Shui, Qing-Cang Chen, Yu-Peng Zhang, Shuang-Nan Kong, Ling-Da Santangelo, A. Yu, Zhuo-Li Ji, Long Wang, Peng-Ju Chang, Zhi Li, Jian Li, Zhao-Sheng Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing100049 China Institute für Astronomie und Astrophysik Kepler Center for Astro and Particle Physics Eberhard Karls Universität Sand 1 TübingenD-72076 Germany School of Physics and Astronomy Sun Yat-Sen University Zhuhai519082 China CAS Key Laboratory for Research in Galaxies and Cosmology Department of Astronomy University of Science and Technology of China Hefei230026 China School of Astronomy and Space Science University of Science and Technology of China Hefei230026 China Key Laboratory of Stars and Interstellar Medium Xiangtan University Hunan Xiangtan411105 China

The systematic properties are largely unknown for the black hole X-ray binary Swift J151857.0–572147 newly discovered in the 2024 outburst. The nature of a black hole can be completely defined by specifying the mass and dimensionless spin parameter. Therefore, accurate measurement of the two fundamental parameters is important for understanding the nature of black holes. The joint spectral fitting of a reflection component with simultaneous observations from Insight-HXMT, NICER and NuSTAR reveals for the first time a black hole dimensionless spin of 0.84+0−01726 and an inclination angle of 21.1+4−356 degree for this system. Monitoring of the soft state by NICER results in disk flux and temperature following Fdisk ∝ Tin3.83±0.17. For the standard thin disk, Ldisk ≈ 4πRin2 σTin4 , so the relationship between the flux and temperature of the disk we measured indicates that the inner radius of the disk is stable and the disk is in the Innermost Stable Circular Orbit. With an empirical relation built previously between the black hole outburst profile and the intrinsic power output, the source distance is estimated as 5.8 ± 2.5 kpc according to the outburst profile and peak flux observed by Insight-HXMT and NICER. Finally, a black hole mass of 3.67 ± 1.79 − 8.07 ± 4.20M☉ can be inferred from a joint diagnostic of the aforementioned parameters measured for this system. This system is also consistent with most black hole X-ray binaries with high spin and a mass in the range of 5–20 M☉ Copyright © 2025, The Authors. All rights reserved.

关键词： Black holes