In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nucl...In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.展开更多
The simultaneous measurement of the spatial profile and spectrum of laser-accelerated protons is important for further optimization of the beam qualities and applications.We report a detailed study regarding the under...The simultaneous measurement of the spatial profile and spectrum of laser-accelerated protons is important for further optimization of the beam qualities and applications.We report a detailed study regarding the underlying physics and regular procedure of such a measurement through the radioactivation of a stack composed of aluminum,copper,and CR-39 plates as well as radiochromic films(RCFs).After being radioactivated,the copper plates are placed on imaging plates(IPs)to detect the positrons emitted by the reaction products through contact imaging.The spectrum and energy-dependent spatial profile of the protons are then obtained from the IPs and confirmed by the measured ones from the RCFs and CR-39 plates.We also discuss the detection range,influence of electrons,radiation safety,and spatial resolution of this measurement.Finally,insights regarding the extension of the current method to online measurements and dynamic proton imaging are also provided.展开更多
In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.De...In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.Demonstration reveals that the theoretical results acquired by CPPM exhibit a high level of consistency with prior theoretical models such as the unified fission model(UFM),generalized liquid-drop model(GLDM)and effective liquid-drop model(ELDM).Furthermore,within the CPPM,we predicted the half-lives of potential 2p radioactive nuclei for which experimental data are currently unavailable.The predicted results were then assessed,compared with UFM,ELDM and GLDM models,and examined in detail.展开更多
基金supported in part by the National Natural Science Foundation of China(Nos. 12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province+4 种基金the Research Foundation of Education Bureau of Hunan Province,China(Nos. 21B0402 and 18A237)the Natural Science Foundation of Hunan Province, China(No. 2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC, the Shandong Province Natural Science Foundation, China(No. ZR2022JQ04)the Hunan Provincial Innovation Foundation for Postgraduates(No.CX20220993)the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No. 2019KFZ10)。
文摘In this study, based on a two-potential approach, we systematically investigated the proton radioactivity half-lives of spherical proton emitters with 69≤Z≤81 from the ground and/or isomeric state, choosing the nuclear potential to be a modified Woods–Saxon potential that contains the isospin effect of the daughter nucleus. It was found that the calculated half-lives could reproduce the experimental data well. Furthermore, we extended this model to predict the half-lives of 17 protonemitting candidates whose radioactivity is energetically allowed or observed but not yet quantified in NUBASE2020. For comparison, the unified fission model, Coulomb potential and proximity potential model, universal decay law for proton emission, and new Geiger–Nuttall law were also used. All the predicted results are consistent with each other.
基金supported by the Institute for Basic ScienceKorea under the project code IBS-R012-D1by the Ultrashort Quantum Beam Facility(UQBF)operation program(No.140011)through APRI,GIST。
文摘The simultaneous measurement of the spatial profile and spectrum of laser-accelerated protons is important for further optimization of the beam qualities and applications.We report a detailed study regarding the underlying physics and regular procedure of such a measurement through the radioactivation of a stack composed of aluminum,copper,and CR-39 plates as well as radiochromic films(RCFs).After being radioactivated,the copper plates are placed on imaging plates(IPs)to detect the positrons emitted by the reaction products through contact imaging.The spectrum and energy-dependent spatial profile of the protons are then obtained from the IPs and confirmed by the measured ones from the RCFs and CR-39 plates.We also discuss the detection range,influence of electrons,radiation safety,and spatial resolution of this measurement.Finally,insights regarding the extension of the current method to online measurements and dynamic proton imaging are also provided.
基金supported by the National Natural Science Foundation of China(Nos.12175100 and 11975132)the Construct Program of the Key Discipline in Hunan Province,the Research Foundation of Education Bureau of Hunan Province,China(No.18A237)+1 种基金the Natural Science Foundation of Hunan Province,China(No.2018JJ2321)the Innovation Group of Nuclear and Particle Physics in USC,the Opening Project of Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment,University of South China(No.2019KFZ10).
文摘In the present work,we extend the Coulomb and Proximity Potential Model(CPPM)to study two-proton(2p)radioactivity from excited states while the proximity potential is chosen as AW95 proposed by Aage Withner in 1995.Demonstration reveals that the theoretical results acquired by CPPM exhibit a high level of consistency with prior theoretical models such as the unified fission model(UFM),generalized liquid-drop model(GLDM)and effective liquid-drop model(ELDM).Furthermore,within the CPPM,we predicted the half-lives of potential 2p radioactive nuclei for which experimental data are currently unavailable.The predicted results were then assessed,compared with UFM,ELDM and GLDM models,and examined in detail.
