Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the...Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms e.g.TabNet show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.展开更多
Based on the characteristics of the interactions between intermediate energy heavy-ion beam and target matter, a method to calculate the depth-dose distribution of heavy-ion beams with intermediate energy (10-100 MeV/...Based on the characteristics of the interactions between intermediate energy heavy-ion beam and target matter, a method to calculate the depth-dose distribution of heavy-ion beams with intermediate energy (10-100 MeV/u) is presented. By comparing high energy beams where projectile fragmentation is overwhelming with low energies where energy straggling is the sole factor instead, a crescent energy spread with increasing depth and a simple fragmentation assumption were included for the depth-dose calculation of the intermediate energy beam. Relative depth-dose curves of carbon and oxygen ion beams with intermediate energies were computed according to the method here. Comparisons between the calculated relative doses and measurements are shown. The calculated Bragg curves, especially the upstream and downstream Bragg peaks, agree with the measured data. Differences between the two results appear only around the peak regions because of the limitations of the calculation and experimental conditions, but the展开更多
In this article,we investigate the dependence of nuclear temperature on emitting source neutron-proton(N/Z)asymmetry with light charged particles(LCPs)and intermediate mass fragments(IMFs)generated from intermediate-v...In this article,we investigate the dependence of nuclear temperature on emitting source neutron-proton(N/Z)asymmetry with light charged particles(LCPs)and intermediate mass fragments(IMFs)generated from intermediate-velocity sources in thirteen reaction systems with different N/Z asymmetries,^(64)Zn on^(112)Sn,and^(70)Zn,^(64)Ni on^(112,124)Sn,^(58,64)Ni,^(197)Au,and^(232)Th at 40 MeV/nucleon.The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers,respectively.Then,the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model.The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect.A negligible N/Z asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy,where a change of o.1 units in source N/Z asymmetry corresponds to an absolute change in temperature of an order of 0.03 to 0.29 MeV on average for LCPs and IMFs.This conclusion is in close agreement with that inferred qualitatively via the indirect method in our previous studies.展开更多
基金This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB34030000)the National Key Research and Development Program of China(No.2022YFA1602404)+1 种基金the National Natural Science Foundation(No.U1832129)the Youth Innovation Promotion Association CAS(No.2017309).
文摘Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms e.g.TabNet show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.
基金This work was jointly supported by the Western Hope Project of the Chinese Academy of Sciences (Grant No. XB010612) the Director Foundation of the Institute of Modern Physics, the Chinese Academy of Sciences (Grant No. ZY010606).
文摘Based on the characteristics of the interactions between intermediate energy heavy-ion beam and target matter, a method to calculate the depth-dose distribution of heavy-ion beams with intermediate energy (10-100 MeV/u) is presented. By comparing high energy beams where projectile fragmentation is overwhelming with low energies where energy straggling is the sole factor instead, a crescent energy spread with increasing depth and a simple fragmentation assumption were included for the depth-dose calculation of the intermediate energy beam. Relative depth-dose curves of carbon and oxygen ion beams with intermediate energies were computed according to the method here. Comparisons between the calculated relative doses and measurements are shown. The calculated Bragg curves, especially the upstream and downstream Bragg peaks, agree with the measured data. Differences between the two results appear only around the peak regions because of the limitations of the calculation and experimental conditions, but the
基金Supported by the National Natural Science Foundation of China(12275186,11705242,12175156,11805138,11905120)the Fundamental Research Funds For the Central Universities in China(YJ201954,YJ201820)。
文摘In this article,we investigate the dependence of nuclear temperature on emitting source neutron-proton(N/Z)asymmetry with light charged particles(LCPs)and intermediate mass fragments(IMFs)generated from intermediate-velocity sources in thirteen reaction systems with different N/Z asymmetries,^(64)Zn on^(112)Sn,and^(70)Zn,^(64)Ni on^(112,124)Sn,^(58,64)Ni,^(197)Au,and^(232)Th at 40 MeV/nucleon.The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers,respectively.Then,the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model.The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect.A negligible N/Z asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy,where a change of o.1 units in source N/Z asymmetry corresponds to an absolute change in temperature of an order of 0.03 to 0.29 MeV on average for LCPs and IMFs.This conclusion is in close agreement with that inferred qualitatively via the indirect method in our previous studies.