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高能重离子碰撞中心快度区鉴别粒子的平均横动量

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物理学报 2024年第18期73卷 98-111页

作者：谢浈李景行郑华张文超朱励霖刘星泉谭志光周代梅 bonasera aldo 陕西师范大学物理学与信息技术学院西安710119 华中师范大学夸克与轻子物理教育部重点实验室武汉430079 四川大学物理学院成都610064 四川大学原子核科学技术研究所成都610064 长沙学院电子信息与电气工程学院长沙410003 华中师范大学粒子物理研究所武汉430079 德州农工大学回旋加速器实验室美国得克萨斯州大学城TX 77843 意大利南方国家实验室意大利卡塔尼亚95123

末态粒子的平均横动量T>是高能重离子碰撞实验中的一个重要观测量.它反映了软质强子的特性和热核物质的性质,对其研究有助于获取碰撞系统的演化信息与规律.基于相对论重离子对撞机(RHIC)上的STAR、PHENIX实验组和大型强子对撞机(LHC)的A... 详细信息

末态粒子的平均横动量T>是高能重离子碰撞实验中的一个重要观测量.它反映了软质强子的特性和热核物质的性质,对其研究有助于获取碰撞系统的演化信息与规律.基于相对论重离子对撞机(RHIC)上的STAR、PHENIX实验组和大型强子对撞机(LHC)的ALICE实验组提供的金核-金核(Au+Au)和铅核-铅核(Pb+Pb)碰撞中心快度区实验数据,唯象公式能很好地描述不同碰撞能量下,鉴别粒子平均横动量T>随碰撞中心度、每核子对的平均碰撞次数、每核子对平均产生的带电粒子多重数赝快度密度及每次碰撞平均产生的带电粒子多重数赝快度密度的依赖关系.结果表明,鉴别粒子平均横动量T>与碰撞中心度呈线性关系,而与每核子对的平均碰撞次数2N_(coll)/N_(part)、每核子对平均产生的带电粒子多重数赝快度密度2/N_(part)dN_(ch)/dη及每次碰撞平均产生的带电粒子多重数赝快度密度1/N_(coll)dN_(ch)/dη呈幂律关系.同时,发现鉴别粒子平均横动量T>与碰撞中心度以及每核子对的平均碰撞次数唯象公式中的拟合参数与碰撞能量呈现非常好的幂律函数关系.因此,碰撞中心度及每核子对的平均碰撞次数是研究鉴别粒子平均横动量的优选物理量.本文结果可用于对实验上在其他碰撞能量下鉴别粒子平均横动量的预测.

关键词：重离子碰撞平均横动量鉴别粒子中心快度区

Density and temperature of fermions and bosons from quantum fluctuations

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Nuclear Science and Techniques 2013年第5期24卷 59-66页

作者： ZHENG Hua GIULIANI Gianluca bonasera aldo Cyclotron Institute Texas A & M UniversityCollege Station Department of Physics and Astronomy Texas A & M UniversityCollege Station Laboratori Nazionali del Sud INFNvia Santa Sofia.62Catania 95123Italy

A novel method to determine the density and temperature of a system constituted by fermions and/or bosons is proposed based on quantum *** fermions system,the results in the limit where the reached temperature T is small and where there is no constraint for the reached temperature T compared to the Fermi energy εf at a given density ρ are given,*** and multiplicity fluctuation relations are derived in terms of T/ε*** compared the two set results in the limit when T is much smaller compared to Fermi energy εf and they are consistent,as *** classical limit is also obtained for high temperatures and low *** bosons system,quadrupole and multiplicity fluctuations using Landau's theory of fluctuations near the critical point for a Bose-Einstein condensate(BEC) at a given density ρ are *** an example,we apply our approach to heavy ion collisions using the Constrained Molecular Dynamics model(CoMD) which includes the fermionic *** multiplicity fluctuation quenching for fermions is found in the model and confirmed by experimental *** reproduce the available experimental data better,we propose a modification of the collision term in the approach to include the possibility of α-α *** relevant Bose-Einstein factor in the collision term is properly taken into *** approach increases the yields of bosons relative to fermions closer to *** fluctuations become larger than one as expected.

关键词：量子涨落玻色子费米子温度密度分子动力学模型爱因斯坦凝聚重离子碰撞

Number-of-constituent-quark scaling of elliptic flow:a quantitative study

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Nuclear Science and Techniques 2022年第3期33卷 152-159页

作者： Meng Wang Jun-Qi Tao Hua Zheng Wen-Chao Zhang Li-Lin Zhu aldo bonasera School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Department of Physics Sichuan UniversityChengdu 610064China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFNVia Santa Sofia6295123 CataniaItaly

The number-of-constituent-quark(NCQ)scaling behavior of the elliptic flow of identified particles produced in A+A collisions is studied quantitatively using an empirical function that fits the experimental v_(2) data available from the RHIC and *** most common approach for NCQ scaling involves(1)doing a scaling of the experimental v_(2) data of an identified particle with its NCQ,(2)doing the same to its transverse momentum or energy,then(3)combining all the scaled data and identifying the NCQ behavior by intuitively looking(since the measured experimental data are discrete).We define two variables(d_(1),d_(2))to describe NCQ scaling quantitatively and simultaneously,and identify the approximate region where the NCQ scaling *** approach could be applied to study NCQ or other scaling phenomena in future experiments.

关键词： Number-of-constituent-quark scaling Heavyion collisions Elliptic flow

Pseudo-rapidity distributions of charged particles in asymmetric collisions using Tsallis thermodynamics

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Nuclear Science and Techniques 2023年第11期34卷 120-127页

作者： Jun‑Qi Tao Hong‑Bin He Hua Zheng Wen‑Chao Zhang Xing‑Quan Liu Li‑Lin Zhu aldo bonasera Key Laboratory of Quark&Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610064China Department of Physics Sichuan UniversityChengdu 610064China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis *** fireball model assumes that the experimentally measured particles are produced by fireballs following the Tsallis distribution and it can effectively describe the experimental *** results as well as previous results for d+Au collisions at√S_(NN)=200 GeV GeV and p+Pb collisions at√S_(NN)=5.02 TeV TeV validate that the fireball model based on Tsallis thermodynamics can provide a universal framework for pseudo-rapidity distribution of the charged particles produced in asymmetric collision *** predict the centrality dependence of the total charged particle multiplicity in the p+Al,p+Au and 3He+Au ***,the dependences of the fireball model parameters(y_(0a),y_(0A),σ_(a) and σ_(A))on the centrality and system size are studied.

关键词： Tsallis thermodynamics Fireball model Pseudo-rapidity distribution Heavy-ion collisions Charged particles

On the Expansion and Fate of the Universe

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Journal of Modern Physics 2012年第11期3卷 1722-1726页

作者： aldo bonasera Laboratori Nazionali del Sud INFN Catania Italy

The evolution of the universe from an initial dramatic event, the Big-Bang, is firmly established. Hubble’s law [1] (HL) connects the velocity of galactic objects and their relative distance: v(r) = Hr, where H is the Hubble constant. In this work we suggest that HL is not valid at large distances because of total energy conservation. We propose an expansion of the velocity in terms of their relative distance and produce a better fit to the available experimental data. Using a simple “dust” universe model, we can easily calculate under which conditions an (unstable) equilibrium state can be reached and we estimate the values of the matter present in the universe as well as the “dark energy”. Within the same formalism we can derive the “deceleration parameter”. We do not need to invoke any “dark energy”, its role being played by the kinetic correction. The resulting picture is that the universe might reach an unstable equilibrium state whose fate will be decided by fluctuations: either collapse or expand forever.

关键词： Big-Bang Hubble’s Law

Controlling the Worldwide Chaotic Spreading of COVID-19 through Vaccinations

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Journal of Modern Physics 2022年第1期13卷 1-15页

作者： Hua Zheng aldo bonasera School of Physics and Information Technology Shaanxi Normal University Xi’an China Cyclotron Institute Texas A&M University College Station USA Laboratori Nazionali del Sud INFN Catania Italy

The striking differences and similarities between the “Spanish-flu” of 1918 and the Coronavirus disease of 2019 (COVID-19) are analyzed. Progress in medicine and technology and in particular the availability of vaccines has decreased the death probability from about 2% for the Spanish-flu, to about 10-4 in the UK and 10-3 in Italy, USA, Canada, San Marino and other countries for COVID-19. The logistic map reproduces most features of the disease and may be of guidance for predictions and future steps to be taken in order to contrast the virus. We estimate 6.4 × 107 deceases worldwide without the vaccines, this value decreases to 1.6 × 107 with the current vaccination rate. In November 2021, the number of deceased worldwide was 5.1 × 106. To reduce the fatalities further, it is imperative to increase the vaccination rate worldwide to at least 120 millions/day and the AstraZeneca vaccine due to its efficacity and cost is a possible route to accomplish this.

关键词： COVID-19 Vaccination Logistic Map

Thermodynamic properties at the kinetic freeze-out in the Au + Au and Cu + Cu collisions at the RHIC using the Tsallis distribution

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Nuclear Science and Techniques 2023年第10期34卷 73-82页

作者： Wei-Hao Wu Jun-Qi Tao Hua Zheng Wen-Chao Zhang Xing-Quan Liu Li-Lin Zhu aldo bonasera School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610064China Department of Physics Sichuan UniversityChengdu 610064China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

The thermodynamic properties of charged particles,such as the energy density,pressure,entropy density,particle density,and squared speed of sound at the kinetic freeze-out in the Au+Au collisions from the relativistic heavy ion collider (RHIC)beam energy scan program √S_(NN) and in the Cu+Cu collisions at √S_(NN),200 GeV are studied using the thermodynamically consistent Tsallis *** energy density,pressure,and particle density decrease monotonically with the collision energy for the same collision centrality;These properties also decrease monotonically from the central to peripheral collisions at the same collision *** the scaled energy densityε∕T^(4) and scaled entropy density s∕T^(3) demonstrate the opposite trend with the collision energy for the same collision *** is a correlation betweenε∕T^(4) and s∕T^(3) at the same *** addition,the squared speed of sound was calculated to determine that all the collision energies share nearly the same value at different collision centralities.

关键词： Heavy-ion collision Tsallis distribution Kinetic freeze-out Energy density Entropy density Particle density Squared speed of sound Pressure

Primary yields of protons measured using CR-39 in laser-induceddeuteron–deuteron fusion reactions

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Nuclear Science and Techniques 2020年第6期31卷 90-98页

作者： Yue Zhang Long-Xiang Liu Hong-Wei Wang Yu-Gang Ma Bai-Fei Shen Guo-Qiang Zhang Mei-Rong Huang aldo bonasera Wen-Peng Wang Jian-Cai Xu Shun Li Gong-Tao Fan Xi-Guang Cao Yong Yu Jian-Jun He Chang-Bo Fu Suyalatu Zhang Xin-Rong Hu Xin-Xiang Li Zi-Rui Hao Jun-Wen Wang Han Xue Hai-Juan Fu Shanghai Institute of Applied Physics CASShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute CASShanghai 201210China Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsCASShanghai 201800China Department of Physics Shanghai Normal UniversityShanghai 200234China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China College of Physics and Electronics Information Inner Mongolia University for NationalitiesTongliao 028000China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFNVia Santa Sofia6295123 CataniaItaly Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China ShanghaiTech University Shanghai 201210China Shanghai University Shanghai 200444China

Investigating deuteron–deuteron(DD)fusion reactions in a plasma environment similar to the early stages of the Big Bang is an important topic in nuclear *** this study,we experimentally investigated such reactions,using eight laser beams with the third harmonic impacting on a deuterated polyethylene target at the ShenGuang-II Upgrade laser *** work focused on the application of range-filter(RF)spectrometers,assembled from a 70 lm aluminum filter and two CR-39 nuclear track detectors,to measure the yields of primary *** on the track diameter calibration results of 3 MeV protons used to diagnose the tracks on the RF spectrometers,an approximate primary DD-proton yield of(8.5±1.7)×10^6 was obtained,consistent with the yields from similar laser facilities *** indicates that the RF spectrometer is an effective way to measure primary ***,due to the low yields of D^3He-protons and its small track diameter,CR-39 detectors were unable to distinguish it from the background *** other accurate detectors may help to measure these rare events.

关键词： Deuteron-deuteron fusion CR-39 Rangefilter spectrometer DD-proton

Yield ratio of neutrons to protons in 12C（d,n）13N and 12C（d,p）13C from 0.6 to 3 MeV

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Nuclear Science and Techniques 2019年第12期30卷 65-71页

作者： Wu-Jie Li Yu-Gang Ma Guo-Qiang Zhang Xian-Gai Deng Mei-Rong Huang aldo bonasera De-Qing Fang Jian-Qing Cao Qi Deng Yong-Qi Wang Qian-Tao Lei Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100080China Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China College of Physics and Electronics Information Inner Mongolia University for NationalitiesTongliao 028000China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFNvia Santa Sofia6295123 CataniaItaly

The neutron yield in the12C(d,n)13N reaction and the proton yield in the12C(d,p)13C reaction have been measured using deuteron beams of energies 0.6-3 *** deuteron beam is delivered from a 4-MeV electrostatic accelerator and bombarded on a thick carbon *** neutrons are detected at 0°,24°,and 48°and the protons at135°in the laboratory ***,the ratio of the neutron yield to the proton yield was *** can be used to effectively recognize the *** resonances are found at 1.4 MeV,1.7 MeV,and 2.5 MeV in the12C(d,p)13C reaction,and at 1.6 MeV and 2.7 MeV in the12C(d,n)13N *** proposed method provides a way to reduce systematic uncertainty and helps confirm more resonances in compound nuclei.

关键词： Proton neutron ratio 12C(d n) p) Trojan horse method(THM)