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Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 43-50页

作者： Ligong Bian Shuailiang Ge Changhong Li Jing Shu Junchao Zong department of physics and Chongqing Key Laboratory for Strongly Coupled physics Chongqing University Center for High Energy physics Peking University School of physics and State Key Laboratory of Nuclear physics and Technology Peking University department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan Province School of Physics and AstronomyYunnan University Beijing Laser Acceleration Innovation Center department of physics Nanjing University CAS Key Laboratory of theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences

We explore the possibility that domain wall networks generate the stochastic gravitational wave background（SGWB） observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σDW～（29-414 TeV）3and wall-decay temperature within Td～ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ?GW（fp, T0）h2～ ?radh2(?ν?Neff)2,to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.

关键词： domain wall gravitational waves Hubble tension

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Cholesterol-induced deformation of the gramicidin A channel inhibiting potassium ion binding and transport

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Chinese physics B 2024年第5期33卷 696-702页

作者：肖盼曹宇朱瑾梁清 Center for Statistical and theoretical Condensed Matter physics & department of physics Zhejiang Normal UniversityJinhua 321004China Zhejiang institute of Photoelectronics & Zhejiang institute for Advanced Light Source Zhejiang Normal UniversityJinhua 321004China

Gramicidin A(gA)is a kind of antibiotic peptide produced by bacillus brevis and it can dimerize across lipid bilayers to form a monovalent cation *** this work,we investigate the impact of cholesterol in the lipid bilayer on the binding of potassium ions with the gA channel and the transport of the ions across the *** results indicate that cholesterol can significantly influence the conformational stability of the gA channel and cause the channel deformation which inhibits the potassium ion binding with the channel and transport across the *** work provides some molecular insights into understanding of influence of lipids on the activity of gA channel in both model membranes and plasma membranes of intact cells.

关键词： gramicidin A lipid bilayer molecular dynamics interaction

Unveiling the Re,Cr,and I diffusion in saturated compacted bentonite using machine-learning methods

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Nuclear Science and Techniques 2024年第6期35卷 65-77页

作者： Zheng-Ye Feng Jun-Lei Tian Tao Wu Guo-Jun Wei Zhi-Long Li Xiao-Qiong Shi Yong-Jia Wang Qing-Feng Li department of Engineering Huzhou UniversityHuzhou 313000China institute of theoretical physics Shanxi UniversityTaiyuan 030006China College of physics Science and Technology Shenyang Normal UniversityShenyang 110034China

The safety assessment of high-level radioactive waste repositories requires a high predictive accuracy for radionuclide diffusion and a comprehensive understanding of the diffusion *** this study,a through-diffusion method and six machine-learning methods were employed to investigate the diffusion of ReO_(4)^(−),HCrO_(4)^(−),and I−in saturated compacted bentonite under different salinities and compacted dry *** machine-learning models were trained using two *** dataset contained six input features and 293 instances obtained from the diffusion database system of the Japan Atomic Energy Agency(JAEA-DDB)and 15 *** other dataset,comprising 15,000 pseudo-instances,was produced using a multi-porosity model and contained eight input *** results indicate that the former dataset yielded a higher predictive accuracy than the *** gradient-boosting exhibited a higher prediction accuracy(R2=0.92)and lower error(MSE=0.01)than the other machine-learning *** addition,Shapley Additive Explanations,Feature Importance,and Partial Dependence Plot analysis results indicate that the rock capacity factor and compacted dry density had the two most significant effects on predicting the effective diffusion coefficient,thereby offering valuable insights.

关键词： Machine learning Effective diffusion coefficient Through-diffusion experiment Multi-porosity model Global analysis

Revisiting the N = 1 supersymmetric trinification models from intersecting D6-branes

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Communications in theoretical physics 2024年第9期76卷 29-38页

作者： Adeel Mansha Tianjun Li Mudassar Sabir department of physics Zhejiang Normal University Zhejiang institute of Photoelectronics Zhejiang Normal University Centre For High Energy physics University of the Punjab CAS Key Laboratory of theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences School of physics University of Electronic Science and Technology of China

We revisit the construction of the N= 1 supersymmetric trinification models with gauge group U（3）C× U（3）L× U（3）Rin Type ⅡA string theory on T6（Z2×Z2）orientifold with intersecting D6-branes. The non-trivial K-theory conditions and tadpole cancellation conditions severely restrict the number of allowed models even for the case of rectangular two-tori. Using a supervised search algorithm, we find a few four-family models where the highest wrapping number is 2. For these models, we present the complete particle spectra and the gauge coupling relations at the string-scale.

关键词： D branes string phenomenology trinification

Exploring hidden-charm and hidden-strange hexaquark states from lattice QCD

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Science China(physics,Mechanics & Astronomy) 2024年第1期67卷 30-37页

作者： Hang Liu Jinchen He Liuming Liu Peng Sun Wei Wang Yi-Bo Yang Qi-An Zhang INPAC Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologySchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Maryland Center for Fundamental physics Department of PhysicsUniversity of MarylandCollege ParkMaryland 20742USA institute of Modern physics Chinese Academy of SciencesLanzhou 730000China university of Chinese Academy of Sciences Beijing 100049China department of physics and institute of theoretical physics Nanjing Normal UniversityNanjing 210023China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China CAS Key Laboratory of theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for theoretical physics Asia-Pacific Beijing 100049/Hangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of physics Beihang UniversityBeijing 102206China

Based on five different ensembles of newly generated(2+1)-flavor configurations with pion mass of approximately mπ■(140-310)MeV,we present a lattice analysis of hidden-charm and hidden-strange hexaquarks with the quark content■.The correlation matrices of two types of operators with JPC=0++,0-+,1++and 1--are simulated to extract the masses of the hexaquark candidates,which are subsequently extrapolated to the physical pion mass and continuum *** results indicate that ground state masses are below the■threshold and provide a characteristic signal for the experimental discovery of hexaquark candidates,which may enrich the versatile structure of multiquarks;moreover,it is an indispensable step to decipher the nonperturbative nature of the fundamental interactions of quarks and gluons.

关键词： quantum chromodynamics lattice QCD multiquark states

Footprints of axion-like particle in pulsar timing array data and James Webb Space Telescope observations

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Science China(physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 59-66页

作者： Shu-Yuan Guo Maxim Khlopov Xuewen Liu Lei Wu Yongcheng Wu Bin Zhu department of physics Yantai University institute of physics Southern Federal University National Research Nuclear university MEPhI (Moscow Engineering physics institute) Virtual institute of Astroparticle physics department of physics and institute of theoretical physics Nanjing Normal University

Several pulsar timing array(PTA) collaborations have recently reported the evidence for a stochastic gravitational-wave background(SGWB), which can unveil the formation of primordial seeds of inhomogeneities in the early universe. With the SGWB parameters inferred from PTAs data, we can make a prediction of the seeds for early galaxy formation from the domain walls in the axion-like particles(ALPs) field distribution. This also naturally provides a solution to the observation of high redshifts by the James Webb Space Telescope. The predicted photon coupling of the ALP is within the reach of future experimental searches.

关键词： stochastic gravitational-wave background pulsar timing array axion-like particle JWST

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Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： Yu-Mei Wu Zu-Cheng Chen Qing-Guo Huang School of Fundamental physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China department of physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

Weak Merging Scenario of CLASH Cluster A209

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Research in Astronomy and Astrophysics 2024年第4期24卷 174-182页

作者： Wen-Cheng Feng Heng Yu Hai-Hui Zhao Xiao-Lan Hou Shu-Mei Jia Cheng-Kui Li Yu-Lin Cheng Paolo Tozzi Ming Sun Yong Chen department of physics and institute of theoretical physics Nanjing Normal UniversityNanjing 210023China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China department of Astronomy Beijing Normal UniversityBeijing 100875China department of Astronomy Yunnan UniversityKunming 650091China INAF—Osservatorio Astrofisico di Arcetri Largo E.Fermi50122 FirenzeItaly department of Astronomy University of VirginiaP.O.Box 400325CharlottesvilleVA 22904-4325USA

We study the structural and dynamical properties of A209 based on Chandra and XMM-Newton *** obtain detailed temperature,pressure,and entropy maps with the contour binning method,and find a hot region in the NW *** X-ray brightness residual map and corresponding temperature profiles reveal a possible shock front in the NW direction and a cold front feature in the SE *** with the galaxy luminosity density map we propose a weak merger scenario.A young sub-cluster passing from the SE to NW direction could explain the optical subpeak,the intracluster medium temperature map,the X-ray surface brightness excess,and the X-ray peak offset together.

关键词： X rays:galaxies:clusters galaxies:clusters:intracluster medium galaxies:clusters:Abell 209

Supermassive black holes triggered by QCD axion bubbles

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Communications in theoretical physics 2024年第5期76卷 134-139页

作者： Hai-Jun Li Ying-Quan Peng Wei Chao Yu-Feng Zhou Key Laboratory of theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for theoretical physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion