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Unraveling the early universe’s equation of state and primordial black hole production with PTA,BBN,and CMB observations

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Chinese physics C 2024年第12期48卷 212-220页

作者： Qing-Hua Zhu Zhi-Chao Zhao Sai Wang Xin Zhang Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Department of Applied Physics College of ScienceChina Agricultural UniversityQinghua East RoadBeijing 100083China Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China

Pulsar timing array(PTA)data releases show strong evidence for a stochastic gravitational-wave background in the nanohertz *** the signal is interpreted by a scenario of scalar-induced gravitational waves(SIGWs),we encounter overproduction of primordial black holes(PBHs).We wonder if varying the equation of state(EoS)of the early Universe can resolve this issue and thereby lead to a consistent interpretation of the PTA *** a data combination of PTA,big-bang nucleosynthesis,and cosmic microwave background,we find that an epoch with EoS w~O(10^(-2))between the end of inflation and the onset of radiation domination can significantly suppress the production of PBHs,leading to alleviation of the PBH-overproduction *** the inferred interval w=0.44_(-0.40)^(+0.52)at 95%confidence level,our scenario can interpret the PTA data just as well as the conventional scenario of SIGWs produced during the radiation domination.

关键词： physics of the early universe gravitational waves primordial black hole pulsar timing arrays

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Single inclusive hadron production at the LHC with an improved impact parameter dependent saturation model

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Chinese physics C 2023年第6期47卷 89-98页

作者：弓晓锋蔡燕兵周代翠向文昌 Guizhou Science and Technology Information Center Guiyang 550002China Guizhou Key Laboratory of Big Data Statistic Analysis and Guizhou Key Laboratory in Physics and Related AreasGuizhou University of Finance and EconomicsGuiyang 550025China Key Laboratory of Quark and Lepton Physics(MOE) and Institute of Particle PhysicsCentral China Normal UniversityWuhan 430079China Physics Division Guangzhou Maritime UniversityGuangzhou 510725China

To obtain a reasonable description of the hadron production at the LHC energies,the impact parameter dependent saturation model is modified by inclusion of an anomalous dimensionγ,which controls the slope of the scattering amplitude in the transition from the dilute region to the saturation *** calculate the transverse momentum distribution and nuclear modification factor of theπ^(0)and charged hadrons with the improved model,and the results are consistent with measurements performed at the ***,we use the original impact parameter dependent model to study the aforementioned measurements performed at the LHC by adjusting its *** find that the improved model is more consistent with the experimental data than the original one,as the anomalous dimension plays a significant role in the suppression of the evolution of the scattering amplitude.

关键词： gluon saturation high energy heavy ion collisions small-x physics

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Evolution and detection of vector superradiant instabilities

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Physical Review D 2024年第8期110卷 083029页

作者： Yin-Da Guo Nayun Jia Shou-Shan Bao Hong Zhang Xin Zhang Key Laboratory of Particle Physics and Particle Irradiation (Ministry of Education) Institute of Frontier and Interdisciplinary Science Department of Physics Key Laboratory of Cosmology and Astrophysics (Liaoning) and College of Sciences Key Laboratory of Data Analytics and Optimization for Smart Industry (Ministry of Education) National Frontiers Science Center for Industrial Intelligence and Systems Optimization

Ultralight vectors can extract energy and angular momentum from a Kerr black hole (BH) due to superradiant instability, resulting in the formation of a BH-condensate system. In this work, we carefully investigate the evolution of this system numerically with multiple superradiant modes. Simple formulas are obtained to estimate important timescales, maximum masses of different modes, as well as the BH mass and spin at various times. Due to the coexistence of modes with small frequency differences, the BH-condensate system emits gravitational waves with a unique beat signature, which could be directly observed by current and projected interferometers. Besides, the current BH spin-mass data from the binary BH merger events already exclude the vector mass in the range 5×10−15 eV<μ<9×10−12 eV.

关键词： Gravitational wave sources Phenomenology Vector mesons

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Stochastic interpolants with data-dependent couplings 24

Stochastic interpolants with data-dependent couplings

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Proceedings of the 41st International Conference on Machine Learning

作者： Michael S. Albergo Mark Goldstein Nicholas M. Boffi Rajesh Ranganath Eric Vanden-Eijnden Center for Cosmology and Particle Physics New York University Courant Institute of Mathematical Sciences New York University Courant Institute of Mathematical Sciences New York University and Center for Data Science New York University

Generative models inspired by dynamical transport of measure - such as flows and diffusions - construct a continuous-time map between two probability densities. Conventionally, one of these is the target density, only accessible through samples, while the other is taken as a simple base density that is data-agnostic. In this work, using the framework of stochastic interpolants, we formalize how to couple the base and the target densities, whereby samples from the base are computed conditionally given samples from the target in a way that is different from (but does not preclude) incorporating information about class labels or continuous embeddings. This enables us to construct dynamical transport maps that serve as conditional generative models. We show that these transport maps can be learned by solving a simple square loss regression problem analogous to the standard independent setting. We demonstrate the usefulness of constructing dependent couplings in practice through experiments in super-resolution and in-painting. The code is available at https://***/interpolants/couplings.

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Reconstruction of aether scalar tensor theory for variouscosmological scenarios

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Chinese physics C 2024年第4期48卷 202-208页

作者：付启铭何梦慈眭陶陶张鑫 Institute of Physics Shaanxi University of TechnologyHanzhong 723000China College of Physics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China 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

In this paper,we present several explicit reconstructions for the aether scalar tensor(AeST)theory derived from the background of the Friedmann-Lemaître-Robertson-Walker cosmological *** is shown that the Einstein-Hilbert Lagrangian with a positive cosmological constant is the only Lagrangian capable of accurately replicating the exact expansion history of theΛcold dark matter(ΛCDM)universe filled solely with dust-like ***,theΛCDM-era can be produced within the framework of the AeST theory for some other fluids,including a perfect fluid with p=−(1/3)ρ,multifluids,and nonisentropic perfect ***,we demonstrate that theΛCDM-era can be replicated with no real matter field for the AeST *** cosmic evolution resulting from both the power-law and de-Sitter solutions can also be obtained.

关键词： reconstruction modified gravity cosmology

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Joint constraints on cosmological parameters using future multi-band gravitational wave standard siren observations

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Chinese physics C 2023年第6期47卷 188-198页

作者：金上捷邢双双邵悦张敬飞张鑫 Key Laboratory of Cosmology and Astrophysics(Liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China 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

Gravitational waves(GWs)from compact binary coalescences can be used as standard sirens to explore the cosmic expansion *** the next decades,it is anticipated that we could obtain the multi-band GW standard siren data(from nanohertz to a few hundred hertz),which are expected to play an important role in cosmological parameter *** this work,we provide,for the first time to the best of our knowledge,joint constraints on cosmological parameters using the future multi-band GW standard siren *** simulate the multi-band GW standard sirens based on the SKA-era pulsar timing array(PTA),Taiji observatory,and Cosmic Explorer(CE)to perform cosmological *** theΛCDM model,we find that the joint PTA+Taiji+CE data could provide a tight constraint on the Hubble constant with a 0.5%***,PTA+Taiji+CE could break the cosmological parameter degeneracies generated by CMB,especially in the dynamical dark energy *** combining the PTA+Taiji+CE data with the CMB data,the constraint precisions of?_(m)and H_(0)are 1.0%and 0.3%,respectively,meeting the standard of precision *** joint CMB+PTA+Taiji+CE data giveσ(_(w))=0.028 in the wCDM model andσ(w_(0))=0.11 andσ(w_(a))=0.32 in the w_(0)w_(a)CDM model,which are comparable with or close to the latest constraint results by CMB+BAO+*** conclusion,the future multi-band GW observations are expected to be used for exploring the nature of dark energy and measuring the Hubble constant.

关键词： gravitational wave standard siren multi-band observations cosmological parameters dark energy

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Maximal flavor violating U(1)Lμ−Lτ model with a singly charged scalar

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Physical Review D 2024年第11期110卷 115047-115047页

作者： Fei Huang Jin Sun School of Physics and Technology University of Jinan 250022 Jinan China Particle Theory and Cosmology Group Center for Theoretical Physics of the Universe Institute for Basic Science (IBS) Daejeon 34126 Korea

The U(1)Lμ−Lτ Z′ model has emerged as a promising candidate to address the longstanding muon (g−2)μ anomaly. Flavor-conserving Z′ interactions are subject to stringent constraints from the neutrino trident process and NA64μ experiments, which limit the Z′ mass to mZ′<40 MeV. To circumvent these constraints, flavor-conserving Z′ interactions can be converted into maximal flavor-violating interactions through a discrete exchange symmetry. Maximal flavor-violating Z′ interactions contribute to τ→μνν¯ via the neutral current, yet the parameter space for this process conflicts with the (g−2)μ allowed regions. To resolve this conflict, we propose introducing a singly charged scalar that mediates via charged current interactions. This scalar is anticipated to produce a negative contribution to the lepton (g−2)l while concurrently inducing the tau decay τ→μνν¯. Three distinct scenarios arise from the introduction of singly charged scalars: the OLL operator, driven by weak singlet and triplet, and the OLR operator, driven by weak doublet. Our analysis of the phenomenology in these three cases reveals that the tension between the muon (g−2)μ anomaly and τ→μνν¯ for large Z′ masses can be effectively alleviated only by the singly charged scalars from the weak triplet, whereas the singlet and doublet scenarios fall short. Furthermore, the singly charged scalars from the weak triplet offer an additional explanation for the electron (g−2)e anomaly. Our findings indicate that weak triplets could play a crucial role in Z′ models, potentially providing valuable insights for future research into U(1) frameworks.

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Elucidating galaxy assembly bias in SDSS

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science China(physics,Mechanics & Astronomy) 2022年第10期65卷 130-150页

作者： Andres N.Salcedo Ying Zu Youcai Zhang Huiyuan Wang Xiaohu Yang Yiheng Wu Yipeng Jing Houjun Mo David HWeinberg Department of Astronomy and Center for Cosmology and AstroParticle Physics The Ohio State UniversityColumbus OH 43210USA Department of Astronomy School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryShanghai 200030China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy University of Massachusetts AmherstAmherst MA 01003USA

We investigate the level of galaxy assembly bias in the Sloan Digital Sky Survey (SDSS) main galaxy sample using ELUCID,a state-of-the-art constrained simulation that accurately reconstructed the initial density perturbations within the SDSS *** top of the ELUCID haloes,we develop an extended HOD model that includes the assembly bias of central and satellite galaxies,parameterized as Q_(cen)and Q_(sat),respectively,to predict a suite of one-and two-point *** particular,our fiducial constraint employs the probability distribution of the galaxy number counts measured on 8 h^(-1)Mpc scales N_8^(g) and the projected cross-correlation functions of quintiles of galaxies selected by N_(8)^(g) with our entire galaxy *** perform extensive tests of the efficacy of our method by fitting the same observables to mock data using both constrained and non-constrained *** discover that in many cases the level of cosmic variance between the two simulations can produce biased constraints that lead to an erroneous detection of galaxy assembly bias if the non-constrained simulation is *** applying our method to the SDSS data,the ELUCID reconstruction effectively removes an otherwise strong degeneracy between cosmic variance and galaxy assembly bias in SDSS,enabling us to derive an accurate and stringent constraint on the *** fiducial ELUCID constraint,for galaxies above a stellar mass threshold M_(*)=10^(10.2)h^(-2)M_(⊙),is Q_(cen)=-0.09±0.05 and Q_(sat)=0.09±0.10,indicating no evidence for a significant (>2σ) galaxy assembly bias in the local Universe probed by ***,our method provides a promising path to the robust modelling of the galaxy-halo connection within future surveys like DESI and PFS.

关键词： spatial distribution of galaxies large scale structure of the Universe numerical simulation

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Measurement of the neutron total cross section of^(9)Be at the Back-n white neutron source of CSNS

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Chinese physics C 2024年第8期48卷 140-152页

作者： Jiangbo Bai Jingyu Tang Liqun Shi Yonghao Chen Han Yi Jie Bao Yu Bao Ping Cao Haolei Chen Zhen Chen Zengqi Cui Ruirui Fan Changqing Feng Keqing Gao Xiaolong Gao MinHao Gu Changcai Han Guozhu He Yongcheng He Yang Hong Yiwei Hu Hanxiong Huang Xiru Huang Haoyu Jiang Wei Jiang Zhijie Jiang Hantao Jing Ling Kang Bo Li Chao Li Jiawen Li Qiang Li Xiao Li Yang Li Jie Liu Shubin Liu Ze Long Guangyuan Luan Changjun Ning Mengchen Niu Binbin Qi Jie Ren Xichao Ruan Zhaohui Song Kang Sun Zhijia Sun Zhixin Tan Xinyi Tang Binbin Tian Lijiao Wang Pengcheng Wang Zhaohui Wang Xiaoguang Wu Xuan Wu Likun Xie Xiaoyun Yang Li Yu Tao Yu Yongji Yu Guohui Zhang Linhao Zhang Qiwei Zhang Xianpeng Zhang Yuliang Zhang Zhiyong Zhang Luping Zhou Zhihao Zhou Kejun Zhu Institute of Modern Physics Fudan UniversityShanghai 200433China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Sate Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Northwest Institute of Nuclear Technology Xi’an 710024China University of Chinese Academy of Sciences Beijing 100049China

The neutron total cross section data of^(9)Be are essential in the nuclear structure model research of light nuclei and nuclear power *** neutron total cross section of^(9)Be in the 0.3 eV−120 MeV energy region has been measured using time-of-flight and transmission methods with the Neutron Total Cross Sectional Spectrometer(NTOX)based on the multi-cell fast fission chamber at the China Spallation Neutron Source(CSNS)-Back-n white neutron source(Back-n).The fission count-neutron energy distributions of ^(235)U and ^(238)U without samples and with Be samples with three thicknesses were measured in the double-bunch operation mode for a beam power of 100 *** Bayesian method was used to eliminate the influence of the double-bunch problem on neutron measurement in the energy region above 10 *** neutron total cross section of^(9)Be results was consistent with ENDF/B-VIII.0 evaluation library data in the 0.3 eV−20 MeV energy *** the energy ranges of 0.3 eV to 10 keV and 0.01 to 20 MeV,the deviations between our results and the evaluation results of ENDF/B-VIII.0 were within 2.5%and 15%,*** the resonance energy region,the measured resonance energies in our experiment were 0.63,0.82,and 2.8 MeV,*** results showed that the total cross section uncertainties of three Be samples were within 2.2%in the energy region below 1 *** total cross section uncertainty of 30 mm Be from ^(235)U was the smallest and less than 5%in the energy region of 0.3 eV−120 *** results of this experiment can provide technical support for further data analysis and related nuclear data evaluation.

关键词： ^(9)Be neutron total cross section CSNS Back-n time-of-flight method transmission method multi-cell fast fission chamber

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Determination of Double Beta Decay Half-Life of 136Xe with the PandaX-4T Natural Xenon Detector

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Research 2023年第2期2022卷 33-41页

作者： Lin Si Zhaokan Cheng Abdusalam Abdukerim Zihao Bo Wei Chen Xun Chen Yunhua Chen Chen Cheng Yunshan Cheng Xiangyi Cui Yingjie Fan Deqing Fang Changbo Fu Mengting Fu Lisheng Geng Karl Giboni Linhui Gu Xuyuan Guo Ke Han Changda He Jinrong He Di Huang Yanlin Huang Zhou Huang Ruquan Hou Xiangdong Ji Yonglin Ju Chenxiang Li Jiafu Li Mingchuan Li Shu Li Shuaijie Li Qing Lin Jianglai Liu Xiaoying Lu Lingyin Luo Yunyang Luo Wenbo Ma Yugang Ma Yujun Mao Yue Meng Nasir Shaheed Xiaofeng Shang Xuyang Ning Ningchun Qi Zhicheng Qian Xiangxiang Ren Changsong Shang Guofang Shen Wenliang Sun Andi Tan Yi Tao Anqing Wang Meng Wang Qiuhong Wang Shaobo Wang Siguang Wang Wei Wang Xiuli Wang Zhou Wang Yuehuan Wei Mengmeng Wu Weihao Wu Jingkai Xia Mengjiao Xiao Xiang Xiao Pengwei Xie Binbin Yan Xiyu Yan Yong Yang Chunxu Yu Jumin Yuan Ying Yuan Zhe Yuan Dan Zhang Minzhen Zhang Peng Zhang Shibo Zhang Shu Zhang Tao Zhang Li Zhao Qibin Zheng Jifang Zhou Ning Zhou Xiaopeng Zhou Yong Zhou IMOE Key Laboratory for Particle Astrophysics and Cosmology Shanghai Key Laboratory for Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Sichuan Research Institute Shanghai Jiao Tong UniversityChengdu 610213China Yalong River Hydropower Development Company Ltd.288 Shuanglin RoadChengdu 610051China School of Physics Sun Yat-sen UniversityGuangzhou 510275China Research Center for Particle Science and Technology Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao266237 ShandongChina Key Laboratory of Particle Physics and Particle Irradiation of Ministry of Education Shandong UniversityQingdao266237 ShandongChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China School of Physics Nankai UniversityTianjin 300071China Key Laboratory NuclearPyics and Ionampplication(MOE)Instituteof ModenPysics Fun Universty Shanghai 200433China School of Physics Peking UniversityBeijing 100871China Schol of Physics Beihang UniversityBejing 100191China International Research Center for Nuclei and Particles in the Cosmos Beijing key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 100191China School of Medical Instrument and Food Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Physics University of MarylandCollge ParkMaryland 20742USA School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratoryof Particle Detetion and Electronics University of Scienceand Technology of ChinaHefei230026China Department of Modern Physics University of Science and Technology of ChinaHefei230026China SJTU ParisElite Instute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

Precise measurement of two-neutrino double beta decay(DBD)half-life is an important step for the searches of Majorana neutrinos with neutrinoless double beta *** report the measurement of DBD half-life of 136xe using the Pandax-4T dual-phase Time Projection Chamber(TPC)with 3.7-tonne natural xenon and the first 94.9-day physics data release.

关键词： decay double Determination

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