In this study,the chemical freeze-out of hadrons,including light-and strange-flavor particles and light nuclei,produced in Au+Au collisions at the Relativistic Heavy Ion Collider(RHIC),was investigated.Using the Therm...In this study,the chemical freeze-out of hadrons,including light-and strange-flavor particles and light nuclei,produced in Au+Au collisions at the Relativistic Heavy Ion Collider(RHIC),was investigated.Using the Thermal-FIST thermodynamic statistical model,we analyzed various particle sets:those inclusive of light nuclei,those exclusive to light nuclei,and those solely comprising light nuclei.We determined the chemical freeze-out parameters at√^(S)NN=7.7–200 Ge V and four different centralities.A significant finding was the decrease in the chemical freeze-out temperature T_(ch)with light-nuclei inclusion,with an even more pronounced reduction when considering light-nuclei yields exclusively.This suggests that light-nuclei formation occurs at a later stage in the system’s evolution at RHIC energies.We present parameterized formulas that describe the energy dependence of T_(ch)and the baryon chemical potentialμ_(B) for three distinct particle sets in central Au+Au collisions at RHIC energies.Our results reveal at least three distinct T_(ch)at RHIC energies correspond to different freeze-out hypersurfaces:a light-flavor freeze-out temperature of T_L=150.2±6 Me V,a strange-flavor freeze-out temperature T_s=165.1±2.7 Me V,and a light-nuclei freeze-out temperature T_(ln)=141.7±1.4 Me V.Notably,at the Large Hadron Collider(LHC)Pb+Pb 2.76Te V,the expected lower freeze-out temperature for light nuclei was not observed;instead,the T_(ch)for light nuclei was found to be approximately 10 Me V higher than that for light-flavor hadrons.展开更多
The transverse momentum spectra of different types of particles produced in central and peripheral gold–gold(Au–Au)and inelastic proton–proton(pp)collisions at the Relativistic Heavy Ion Collider,as well as in cent...The transverse momentum spectra of different types of particles produced in central and peripheral gold–gold(Au–Au)and inelastic proton–proton(pp)collisions at the Relativistic Heavy Ion Collider,as well as in central and peripheral lead-lead(Pb–Pb)and pp collisions at the Large Hadron Collider,are analyzed by the multi-component standard(Boltzmann–Gibbs,Fermi–Dirac,and Bose–Einstein)distributions.The obtained results from the standard distribution give an approximate agreement with the measured experimental data by the STAR,PHENIX,and ALICE Collaborations.The behavior of the effective(kinetic freeze-out)temperature,transverse flow velocity,and kinetic freeze-out volume for particles with different masses is obtained,which observes the early kinetic freezeout of heavier particles as compared to the lighter particles.The parameters of emissions of different particles are observed to be different,which reveals a direct signature of the mass-dependent differential kinetic freeze-out.It is also observed that the peripheral nucleus–nucleus(AA)and pp collisions at the same center-of-mass energy per nucleon pair are in good agreement in terms of the extracted parameters.展开更多
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...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 distribution.The 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 energy.While 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 centrality.There is a correlation betweenε∕T^(4) and s∕T^(3) at the same centrality.In addition,the squared speed of sound was calculated to determine that all the collision energies share nearly the same value at different collision centralities.展开更多
The transverse momentum distributions of the identified particles produced in small collision systems at the Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) have been analyzed by four models. The ...The transverse momentum distributions of the identified particles produced in small collision systems at the Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) have been analyzed by four models. The first two models utilize the blast-wave model with different statistics. The last two models employ certain linear correspondences based on different distributions.The four models describe the experimental data measured by the Pioneering High Energy Nuclear Interaction eXperiment, Solenoidal Tracker at RHIC, and A Large Ion Collider Experiment collaborations equally well. It is found that both the kinetic freeze-out temperature and transverse flow velocity in the central collisions are comparable with those in the peripheral collisions. With the increase of collision energy from that of the RHIC to that of the LHC,the considered quantities typically do not decrease. Comparing with the central collisions, the proton–proton collisions are closer to the peripheral collisions.展开更多
Event shape measurements are crucial for understanding the underlying event and multiple-parton interactions(MPIs)in high energy proton-proton(pp)collisions.In this study,the Tsallis blast-wave model with independent ...Event shape measurements are crucial for understanding the underlying event and multiple-parton interactions(MPIs)in high energy proton-proton(pp)collisions.In this study,the Tsallis blast-wave model with independent non-extensive parameters for mesons and baryons was applied to analyze the transverse momentum spectraof charged pions,kaons,and protons in pp collision events at√S=13TeV classified by event shape estimators such as relative transverse event activity,unweighted transverse spherocity,and flattenicity.Our analysis reveals consistent trends in the kinetic freeze-out temperature and non-extensive parameter across different collision systems and event shape classes.The use of diverse event-shape observables in pp collisions has significantly expanded the accessible freeze-out parameter space,enabling a more comprehensive exploration of its boundaries.Among these event shape classifiers,flattenicity emerges as a unique observable for disentangling hard process contributions from additive MPI effects,which helps isolate collective motion effects encoded by the radial flow velocity.Through the analysis of the interplay between event-shape measurements and kinetic freeze-out properties,we gain deeper insights into mechanisms responsible for flow-like signatures in pp collisions.展开更多
The transverse momentum distributions of charged hadrons produced in proton-proton collisions at center-of-mass energies(√s)of 0.9 TeV and 2.36 TeV,as measured by the CMS detector at the Large Hadron Collider(LHC),ha...The transverse momentum distributions of charged hadrons produced in proton-proton collisions at center-of-mass energies(√s)of 0.9 TeV and 2.36 TeV,as measured by the CMS detector at the Large Hadron Collider(LHC),have been analyzed within various pseudorapidity classes utilizing the thermodynamically consistent Tsallis distribution.The fitting procedure resulted in the key parameters,namely,effective temperature(T),non-extensivity parameter(q),and kinetic freezeout volume(V).Additionally,the mean transverse momentum(<pT>)and initial temperature(T_(i))of the particle source are determined through the fit function and string percolation method,respectively.An alternative method is employed to calculate the kinetic freezeout temperature(T_(0))and transverse flow velocity(β_(T))from T.Furthermore,thermodynamic quantities at the freezeout,including energy density(ε),particle density(n),entropy density(s),pressure(P),and squared speed of sound(C_(s)^(2)),are computed using the extracted T and q.It is also observed that,with a decrease in pseudorapidity,all thermodynamic quantities except V and q increase.This trend is attributed to greater energy transfer along the mid pseudorapidity.q increases towards higher values of pseudorapidity,indicating that particles close to the beam axis are far from equilibrium.Meanwhile,V remains nearly independent of pseudorapidity.The excitation function of these parameters(q)shows a direct(inverse)correlation with collision energy.The ε,n,s,and P show a strong dependence on collision energies at low pseudorapidities.Explicit verification of the thermodynamic inequality ε≥3P suggests the formation of a highly dense droplet-like Quark-Gluon Plasma(QGP).Additionally,the inequality T_(i)>T>T_(0)is explicitly confirmed,aligning with the evolution of the produced fireball.展开更多
The effects of pre-equilibrium emission and secondary decay on the determination of the freeze-out volume are investigated using the isospin-dependent quantum molecular dynamics model accompanied by the statistical de...The effects of pre-equilibrium emission and secondary decay on the determination of the freeze-out volume are investigated using the isospin-dependent quantum molecular dynamics model accompanied by the statistical decay model GEMINI.Small-mass projectiles and large-mass targets with central collisions are studied at intermediate energies.It is revealed that the proton yields of pre-equilibrium emission are smaller than those of secondary decay.However,the determination of the freeze-out volume from the proton yields is more easily affected by pre-equilibrium emission.Moreover,the percentage of proton yields in the freezeout stage is found to be approxim-ately 50%.展开更多
The Shockley-Queisser(S-Q)model sets a theoretical limit on the power conversion efficiency(PCE)of single-junction solar cells at around 33%.Recently,a PCE of 50%-60%was achieved for the first time in n-type singlejun...The Shockley-Queisser(S-Q)model sets a theoretical limit on the power conversion efficiency(PCE)of single-junction solar cells at around 33%.Recently,a PCE of 50%-60%was achieved for the first time in n-type singlejunction Si solar cells by inhibiting light conversion to heat at low temperatures.Understanding these new observations opens tremendous opportunities for designing solar cells with even higher PCE to provide efficient and powerful energy sources for cryogenic devices and outer and deep space explorations.展开更多
We study the centrality dependence of the mid-rapidity （｜y｜ 〈 0.5） yields and transverse momentum distributions of K＊ （892）° and φ（1020） resonances produced in Pb ＋ Pb collisions at SNN= 2.76 TeV. The...We study the centrality dependence of the mid-rapidity （｜y｜ 〈 0.5） yields and transverse momentum distributions of K＊ （892）° and φ（1020） resonances produced in Pb ＋ Pb collisions at SNN= 2.76 TeV. The mid- rapidity density （dN/dy） and the shape of the transverse momentum spectra are well reproduced by an earlier proposed Unified Statistical Thermal Freeze-out Model （USTFM）, which incorporates the effects of both longitudinal as well as transverse hydrodynamic flow. The freeze-out properties in terms of kinetic freeze-out temperature and transverse flow velocity parameter are extracted from the model fits to the transverse momentum data provided by the ALICE experiment at the LHC. The kinetic freeze-out temperature is found to increase with decreasing event centrality while the transverse flow velocity parameter shows a mild decrease on moving towards peripheral collisions. Moreover the centrality dependence of the mid-rapidity system size at freeze-out has also been studied in terms of transverse radius parameter.展开更多
The emission of high-energy particles in 16O + 197Au collisions at energy 20 MeV / nucleon is considered within the framework of the time evolution of a hot spot taking into account the hydrodynamic compression and ex...The emission of high-energy particles in 16O + 197Au collisions at energy 20 MeV / nucleon is considered within the framework of the time evolution of a hot spot taking into account the hydrodynamic compression and expansion stages. In addition, the evaporation of the particles that are formed in the early (hot) stage of the evolution of the hot spot is included in the calculation of the spectrum. This leads to a hardening of the particle spectrum in its high-energy part, which is in agreement with experimental data.展开更多
The blast wave model with Tsallis statistics is used to analyze the transverse momentum spectra of protons(p),deuterons(d),and tritons(t)in√S_(NN)=200 GeV gold-gold(Au-Au)collisions at the RHIC in various centrality ...The blast wave model with Tsallis statistics is used to analyze the transverse momentum spectra of protons(p),deuterons(d),and tritons(t)in√S_(NN)=200 GeV gold-gold(Au-Au)collisions at the RHIC in various centrality bins.In particular transverse momentum ranges,the model results closely match experimental data from the PHENIX(p)and STAR(d and t)collaborations.The data are compared with those of protons obtained in Cu+Cu collisions and deuterons and tritons in Ru+Ru collisions at a center of mass energy of 200 GeV from the STAR collaboration.Particle spectra are used to derive the kinetic freeze-out temperatures,transverse flow velocities,and freeze-out volumes.According to the findings,the kinetic freeze-out temperature increases from the central to peripheral collisions.In this transition,the transverse flow velocity and freeze-out volume both decrease.For the collisions of both collaborations,this study reveals mass-dependent kinetic freeze-out temperature and differential volume possibilities.Overall,the non-extensivity parameter q decreases with increasing centrality of the studied heavy-ion collisions,and heavier mass particles have smaller values of q,which implies higher degrees of thermalization and equilibrium in more central collisions and for heavier particles.展开更多
A sub-circuit SPICE model of a MOSFET for low temperature operation is presented.Two resistors are introduced for the freeze-out effect,and the explicit behavioral models are developed for them.The model can be used i...A sub-circuit SPICE model of a MOSFET for low temperature operation is presented.Two resistors are introduced for the freeze-out effect,and the explicit behavioral models are developed for them.The model can be used in a wide temperature range covering both cryogenic temperature and regular temperatures.展开更多
基金supported by the Scientific Research Foundation of Hubei University of Education for Talent Introduction(Nos.ESRC20230002 and ESRC20230007)the Research Project of Hubei Provincial Department of Education(Nos.D20233003 and B2023191)。
文摘In this study,the chemical freeze-out of hadrons,including light-and strange-flavor particles and light nuclei,produced in Au+Au collisions at the Relativistic Heavy Ion Collider(RHIC),was investigated.Using the Thermal-FIST thermodynamic statistical model,we analyzed various particle sets:those inclusive of light nuclei,those exclusive to light nuclei,and those solely comprising light nuclei.We determined the chemical freeze-out parameters at√^(S)NN=7.7–200 Ge V and four different centralities.A significant finding was the decrease in the chemical freeze-out temperature T_(ch)with light-nuclei inclusion,with an even more pronounced reduction when considering light-nuclei yields exclusively.This suggests that light-nuclei formation occurs at a later stage in the system’s evolution at RHIC energies.We present parameterized formulas that describe the energy dependence of T_(ch)and the baryon chemical potentialμ_(B) for three distinct particle sets in central Au+Au collisions at RHIC energies.Our results reveal at least three distinct T_(ch)at RHIC energies correspond to different freeze-out hypersurfaces:a light-flavor freeze-out temperature of T_L=150.2±6 Me V,a strange-flavor freeze-out temperature T_s=165.1±2.7 Me V,and a light-nuclei freeze-out temperature T_(ln)=141.7±1.4 Me V.Notably,at the Large Hadron Collider(LHC)Pb+Pb 2.76Te V,the expected lower freeze-out temperature for light nuclei was not observed;instead,the T_(ch)for light nuclei was found to be approximately 10 Me V higher than that for light-flavor hadrons.
基金supported by the National Natural Science Foundation of China(Nos.11575103 and 11947418)the Chinese Government Scholarship(China Scholarship Council)+2 种基金the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(STIP)(No.201802017)the Shanxi Provincial Natural Science Foundation(No.201901D111043)the Fund for Shanxi‘‘1331 Project’’Key Subjects Construction。
文摘The transverse momentum spectra of different types of particles produced in central and peripheral gold–gold(Au–Au)and inelastic proton–proton(pp)collisions at the Relativistic Heavy Ion Collider,as well as in central and peripheral lead-lead(Pb–Pb)and pp collisions at the Large Hadron Collider,are analyzed by the multi-component standard(Boltzmann–Gibbs,Fermi–Dirac,and Bose–Einstein)distributions.The obtained results from the standard distribution give an approximate agreement with the measured experimental data by the STAR,PHENIX,and ALICE Collaborations.The behavior of the effective(kinetic freeze-out)temperature,transverse flow velocity,and kinetic freeze-out volume for particles with different masses is obtained,which observes the early kinetic freezeout of heavier particles as compared to the lighter particles.The parameters of emissions of different particles are observed to be different,which reveals a direct signature of the mass-dependent differential kinetic freeze-out.It is also observed that the peripheral nucleus–nucleus(AA)and pp collisions at the same center-of-mass energy per nucleon pair are in good agreement in terms of the extracted parameters.
基金supported in part by the National Natural Science Foundation of China (Nos. 11905120 and 11947416)the Natural Science Foundation of the Sichuan Province (No. 2023NSFSC1322)+1 种基金the United States Department of Energy (#DE-FG02-93ER40773)the NNSA (No. DENA0003841 (CENTAUR))。
文摘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 distribution.The 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 energy.While 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 centrality.There is a correlation betweenε∕T^(4) and s∕T^(3) at the same centrality.In addition,the squared speed of sound was calculated to determine that all the collision energies share nearly the same value at different collision centralities.
基金supported by the National Natural Science Foundation of China(Nos.11575103 and 11747319)the Shanxi Provincial Natural Science Foundation(No.201701D121005)+1 种基金the Fund for Shanxi ‘‘1331 Project’’ Key Subjects Constructionthe US DOE(DE-FG02-87ER40331.A008)
文摘The transverse momentum distributions of the identified particles produced in small collision systems at the Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) have been analyzed by four models. The first two models utilize the blast-wave model with different statistics. The last two models employ certain linear correspondences based on different distributions.The four models describe the experimental data measured by the Pioneering High Energy Nuclear Interaction eXperiment, Solenoidal Tracker at RHIC, and A Large Ion Collider Experiment collaborations equally well. It is found that both the kinetic freeze-out temperature and transverse flow velocity in the central collisions are comparable with those in the peripheral collisions. With the increase of collision energy from that of the RHIC to that of the LHC,the considered quantities typically do not decrease. Comparing with the central collisions, the proton–proton collisions are closer to the peripheral collisions.
基金Supported by the National Key Research and Development Program of China(2024YFA1610800)the National Natural Science Foundation of China(12205259,12147101,12275103,12061141008)+2 种基金the Fundamental Research Funds for the Central UniversitiesChina University of Geosciences(Wuhan)with G1323523064the Innovation Fund of Key Laboratory of Quark and Lepton Physics QLPL2025P01。
文摘Event shape measurements are crucial for understanding the underlying event and multiple-parton interactions(MPIs)in high energy proton-proton(pp)collisions.In this study,the Tsallis blast-wave model with independent non-extensive parameters for mesons and baryons was applied to analyze the transverse momentum spectraof charged pions,kaons,and protons in pp collision events at√S=13TeV classified by event shape estimators such as relative transverse event activity,unweighted transverse spherocity,and flattenicity.Our analysis reveals consistent trends in the kinetic freeze-out temperature and non-extensive parameter across different collision systems and event shape classes.The use of diverse event-shape observables in pp collisions has significantly expanded the accessible freeze-out parameter space,enabling a more comprehensive exploration of its boundaries.Among these event shape classifiers,flattenicity emerges as a unique observable for disentangling hard process contributions from additive MPI effects,which helps isolate collective motion effects encoded by the radial flow velocity.Through the analysis of the interplay between event-shape measurements and kinetic freeze-out properties,we gain deeper insights into mechanisms responsible for flow-like signatures in pp collisions.
基金Supported by Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2024R106), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabiathe authors extend their appreciation to the Deanship of Scientific Research at Northern Border University, Arar, KSA for funding this research work through the project number “NBU-FFR-2024-2461-04”University,Riyadh,Saudi Arabia.In addition,the authors extend their appreciation to the Deanship of Scientific Research at Northern Border University,Arar,KSA for funding this research work through the project number“NBU-FFR-2024-2461-04”。
文摘The transverse momentum distributions of charged hadrons produced in proton-proton collisions at center-of-mass energies(√s)of 0.9 TeV and 2.36 TeV,as measured by the CMS detector at the Large Hadron Collider(LHC),have been analyzed within various pseudorapidity classes utilizing the thermodynamically consistent Tsallis distribution.The fitting procedure resulted in the key parameters,namely,effective temperature(T),non-extensivity parameter(q),and kinetic freezeout volume(V).Additionally,the mean transverse momentum(<pT>)and initial temperature(T_(i))of the particle source are determined through the fit function and string percolation method,respectively.An alternative method is employed to calculate the kinetic freezeout temperature(T_(0))and transverse flow velocity(β_(T))from T.Furthermore,thermodynamic quantities at the freezeout,including energy density(ε),particle density(n),entropy density(s),pressure(P),and squared speed of sound(C_(s)^(2)),are computed using the extracted T and q.It is also observed that,with a decrease in pseudorapidity,all thermodynamic quantities except V and q increase.This trend is attributed to greater energy transfer along the mid pseudorapidity.q increases towards higher values of pseudorapidity,indicating that particles close to the beam axis are far from equilibrium.Meanwhile,V remains nearly independent of pseudorapidity.The excitation function of these parameters(q)shows a direct(inverse)correlation with collision energy.The ε,n,s,and P show a strong dependence on collision energies at low pseudorapidities.Explicit verification of the thermodynamic inequality ε≥3P suggests the formation of a highly dense droplet-like Quark-Gluon Plasma(QGP).Additionally,the inequality T_(i)>T>T_(0)is explicitly confirmed,aligning with the evolution of the produced fireball.
基金Supported by the National Natural Science Foundation of China (11905018)Scientific and Technological Innovation Programs of Higher Education Institutions of Shanxi Province,China (2019L0908)
文摘The effects of pre-equilibrium emission and secondary decay on the determination of the freeze-out volume are investigated using the isospin-dependent quantum molecular dynamics model accompanied by the statistical decay model GEMINI.Small-mass projectiles and large-mass targets with central collisions are studied at intermediate energies.It is revealed that the proton yields of pre-equilibrium emission are smaller than those of secondary decay.However,the determination of the freeze-out volume from the proton yields is more easily affected by pre-equilibrium emission.Moreover,the percentage of proton yields in the freezeout stage is found to be approxim-ately 50%.
基金support from the National Natural Science Foundation of China(Grant Nos.52371197,51671139).
文摘The Shockley-Queisser(S-Q)model sets a theoretical limit on the power conversion efficiency(PCE)of single-junction solar cells at around 33%.Recently,a PCE of 50%-60%was achieved for the first time in n-type singlejunction Si solar cells by inhibiting light conversion to heat at low temperatures.Understanding these new observations opens tremendous opportunities for designing solar cells with even higher PCE to provide efficient and powerful energy sources for cryogenic devices and outer and deep space explorations.
基金Supported by Council of Scientific and Industrial Research,New Delhi for This Work
文摘We study the centrality dependence of the mid-rapidity （｜y｜ 〈 0.5） yields and transverse momentum distributions of K＊ （892）° and φ（1020） resonances produced in Pb ＋ Pb collisions at SNN= 2.76 TeV. The mid- rapidity density （dN/dy） and the shape of the transverse momentum spectra are well reproduced by an earlier proposed Unified Statistical Thermal Freeze-out Model （USTFM）, which incorporates the effects of both longitudinal as well as transverse hydrodynamic flow. The freeze-out properties in terms of kinetic freeze-out temperature and transverse flow velocity parameter are extracted from the model fits to the transverse momentum data provided by the ALICE experiment at the LHC. The kinetic freeze-out temperature is found to increase with decreasing event centrality while the transverse flow velocity parameter shows a mild decrease on moving towards peripheral collisions. Moreover the centrality dependence of the mid-rapidity system size at freeze-out has also been studied in terms of transverse radius parameter.
文摘The emission of high-energy particles in 16O + 197Au collisions at energy 20 MeV / nucleon is considered within the framework of the time evolution of a hot spot taking into account the hydrodynamic compression and expansion stages. In addition, the evaporation of the particles that are formed in the early (hot) stage of the evolution of the hot spot is included in the calculation of the spectrum. This leads to a hardening of the particle spectrum in its high-energy part, which is in agreement with experimental data.
文摘The blast wave model with Tsallis statistics is used to analyze the transverse momentum spectra of protons(p),deuterons(d),and tritons(t)in√S_(NN)=200 GeV gold-gold(Au-Au)collisions at the RHIC in various centrality bins.In particular transverse momentum ranges,the model results closely match experimental data from the PHENIX(p)and STAR(d and t)collaborations.The data are compared with those of protons obtained in Cu+Cu collisions and deuterons and tritons in Ru+Ru collisions at a center of mass energy of 200 GeV from the STAR collaboration.Particle spectra are used to derive the kinetic freeze-out temperatures,transverse flow velocities,and freeze-out volumes.According to the findings,the kinetic freeze-out temperature increases from the central to peripheral collisions.In this transition,the transverse flow velocity and freeze-out volume both decrease.For the collisions of both collaborations,this study reveals mass-dependent kinetic freeze-out temperature and differential volume possibilities.Overall,the non-extensivity parameter q decreases with increasing centrality of the studied heavy-ion collisions,and heavier mass particles have smaller values of q,which implies higher degrees of thermalization and equilibrium in more central collisions and for heavier particles.
基金Project supported by the Natural Science Foundation of Jiangsu Province,China(NoBK2008287)the Advanced Research of National Natural Science Foundation of Southeast University,China(NoXJ2008312)
文摘A sub-circuit SPICE model of a MOSFET for low temperature operation is presented.Two resistors are introduced for the freeze-out effect,and the explicit behavioral models are developed for them.The model can be used in a wide temperature range covering both cryogenic temperature and regular temperatures.
