This study uses the AMPT model in Au+Au collisions to study the influence of the three nucleon correlation C_(n^(2)p) on light nuclei yield ratios. Neglecting C_(n^(2)p) results in an overestimated relative neutron de...This study uses the AMPT model in Au+Au collisions to study the influence of the three nucleon correlation C_(n^(2)p) on light nuclei yield ratios. Neglecting C_(n^(2)p) results in an overestimated relative neutron density fluctuation extraction. In contrast, including C_(n^(2)p) enhances the agreement with experimental results with higher yield ratios but does not change the energy dependence of the yield ratio. Since the AMPT model does exhibit a first-order phase transition or critical physics, the study fails to reproduce the experimental energy-dependent peak around sNN1/2=20-30 GeV. The study'us findings might offer a baseline for investigating critical physics phenomena using light nuclei production as a probe.展开更多
High multipole electromagnetic transitions are rare in nature.The highest-multipole transition observed in atomic nuclei is the electric hexacontatetrapole E6 transition from the T_(1/2)=2.54(2)-min J^(π)=1_(9/2)-iso...High multipole electromagnetic transitions are rare in nature.The highest-multipole transition observed in atomic nuclei is the electric hexacontatetrapole E6 transition from the T_(1/2)=2.54(2)-min J^(π)=1_(9/2)-isomer to the 7/2^(-)ground state in^(53)Fe with an angular momentum change of six units.In the present work,we performed ab initio calculations for this unique case by employing chiral effective field theory(EFT)forces.The in-medium similarity renormalization group is used to derive the valence-space effective Hamiltonian and multipolar transition operators.Bare nucleon charges were used in all the multipolar transition rate calculations,providing good agreement with the experimental data.The valence space takes the full fp shell.In^(53)Fe,the low-lying states were dominated by the 0f_(7/2)component.Two different versions of the chiral EFT two-plus three-nucleon interaction were used to test the dependence on the interaction used.We also tested the convergence of the transition rate calculations against the harmonic oscillator parameter hΩand basis truncations e_(max)and E_(3max)for twoand three-nucleon forces,respectively.展开更多
We have investigated the effect of tensor correlations on the depletion of the nuclear Fermi sea in symmetric nuclear matter within the framework of the extended Brueckner-Hartree-Fock approach by adopting the AV 18 t...We have investigated the effect of tensor correlations on the depletion of the nuclear Fermi sea in symmetric nuclear matter within the framework of the extended Brueckner-Hartree-Fock approach by adopting the AV 18 two-body interaction and a microscopic three-body force.The contributions from various partial wave channels including the isospin-singlet T = 0 channel,the isospin-triplet T = 1 channel and the T = 0 tensor 3SD1 channel have been calculated.The T =0 neutron-proton correlations play a dominant role in causing the depletion of nuclear Fermi sea.The T =0 correlation-induced depletion turns out to stem almost completely from the 3SD1 tensor channel.The isospin-singlet T = 0 3SD1 tensor correlations are shown to be responsible for most of the depletion,which amounts to more than 70 percent of the total depletion in the density region considered.The three-body force turns out to lead to an enhancement of the depletion at high densities well above the empirical saturation density and its effect increases as a function of density.展开更多
We report our recent work on a hadronic molecule state of the KKN system with I =1/2 and jR = 1/2+. We assume that the A(1405) resonance and the scalar mesons, f0(980), ao(980), are reproduced as quasi-bound st...We report our recent work on a hadronic molecule state of the KKN system with I =1/2 and jR = 1/2+. We assume that the A(1405) resonance and the scalar mesons, f0(980), ao(980), are reproduced as quasi-bound states of KN and KK, respectively. Performing non-relativistic three-body calculations with a variational method for this system, we find a quasibound state of the KIlN system around 1910 MeV below the three-body breakup threshold. This state corresponds to a new baryon resonance of N* with JP : 1/2+. We find also that this resonance has the cluster structure of the two-body bound states keeping their properties as in the isolated two-particle systems. We also briefly discuss another hadronic molecular state composed by two K and one N, which corresponds to a resonance.展开更多
基金Supported in part by the Scientific Research Foundation of Hubei University of Education for Talent Introduction (ESRC20230002, ESRC20230007)Research Project of Hubei Provincial Department of Education (D20233003, B2023191)。
文摘This study uses the AMPT model in Au+Au collisions to study the influence of the three nucleon correlation C_(n^(2)p) on light nuclei yield ratios. Neglecting C_(n^(2)p) results in an overestimated relative neutron density fluctuation extraction. In contrast, including C_(n^(2)p) enhances the agreement with experimental results with higher yield ratios but does not change the energy dependence of the yield ratio. Since the AMPT model does exhibit a first-order phase transition or critical physics, the study fails to reproduce the experimental energy-dependent peak around sNN1/2=20-30 GeV. The study'us findings might offer a baseline for investigating critical physics phenomena using light nuclei production as a probe.
基金supported by the National Key R&D Program of China(Nos.2024YFA1610900 and 2023YFA1606401)the National Natural Science Foundation of China(Nos.12335007 and 12035001)the United Kingdom Science and Technology Facilities Council(No.ST/V001108/1)。
文摘High multipole electromagnetic transitions are rare in nature.The highest-multipole transition observed in atomic nuclei is the electric hexacontatetrapole E6 transition from the T_(1/2)=2.54(2)-min J^(π)=1_(9/2)-isomer to the 7/2^(-)ground state in^(53)Fe with an angular momentum change of six units.In the present work,we performed ab initio calculations for this unique case by employing chiral effective field theory(EFT)forces.The in-medium similarity renormalization group is used to derive the valence-space effective Hamiltonian and multipolar transition operators.Bare nucleon charges were used in all the multipolar transition rate calculations,providing good agreement with the experimental data.The valence space takes the full fp shell.In^(53)Fe,the low-lying states were dominated by the 0f_(7/2)component.Two different versions of the chiral EFT two-plus three-nucleon interaction were used to test the dependence on the interaction used.We also tested the convergence of the transition rate calculations against the harmonic oscillator parameter hΩand basis truncations e_(max)and E_(3max)for twoand three-nucleon forces,respectively.
基金Supported by National Natural Science Foundation of China(11435014,11175219)the 973 Program of China(2013CB834405)the Knowledge Innovation Project(KJCX2-EW-N01)of the Chinese Academy of Sciences
文摘We have investigated the effect of tensor correlations on the depletion of the nuclear Fermi sea in symmetric nuclear matter within the framework of the extended Brueckner-Hartree-Fock approach by adopting the AV 18 two-body interaction and a microscopic three-body force.The contributions from various partial wave channels including the isospin-singlet T = 0 channel,the isospin-triplet T = 1 channel and the T = 0 tensor 3SD1 channel have been calculated.The T =0 neutron-proton correlations play a dominant role in causing the depletion of nuclear Fermi sea.The T =0 correlation-induced depletion turns out to stem almost completely from the 3SD1 tensor channel.The isospin-singlet T = 0 3SD1 tensor correlations are shown to be responsible for most of the depletion,which amounts to more than 70 percent of the total depletion in the density region considered.The three-body force turns out to lead to an enhancement of the depletion at high densities well above the empirical saturation density and its effect increases as a function of density.
基金Supported by Grant for Scientific Research (18540263, 20028004) from Japan Society for the Promotion of Science (JSPS)and from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. A part of this work is done under Yukawa International Project for Quark-Hadron Sciences (YIPQS). The computational calculations of the present work were done by using the supercomputer at YITP
文摘We report our recent work on a hadronic molecule state of the KKN system with I =1/2 and jR = 1/2+. We assume that the A(1405) resonance and the scalar mesons, f0(980), ao(980), are reproduced as quasi-bound states of KN and KK, respectively. Performing non-relativistic three-body calculations with a variational method for this system, we find a quasibound state of the KIlN system around 1910 MeV below the three-body breakup threshold. This state corresponds to a new baryon resonance of N* with JP : 1/2+. We find also that this resonance has the cluster structure of the two-body bound states keeping their properties as in the isolated two-particle systems. We also briefly discuss another hadronic molecular state composed by two K and one N, which corresponds to a resonance.