Probing in-medium nucleon-nucleon (NN) cross section σ1/NN(α) in heavy ion collisions has been investigated by means of the isospin-dependent quantum molecular dynamics (IQMD) with the isospin- and momentum-de...Probing in-medium nucleon-nucleon (NN) cross section σ1/NN(α) in heavy ion collisions has been investigated by means of the isospin-dependent quantum molecular dynamics (IQMD) with the isospin- and momentum-dependent interaction (IMDI(T)). It is found that there are the very obvious medium effect and the sensitive isospin-dependence of nuclear stopping R on the in-medium NN cross section α1/NN(α) in the nuclear reactions induced by halo-neutron projectile and the same-mass stable projectile. However, R induced by the neutron-halo projectile is obviously lower than that induced by the corresponding stable projectile. In particular, there is a very obvious dependence of R on the medium effect of σ1/NN(α) in the whole beam energy region for the above two kinds of projectiles. Therefore, the comparison between the results of R's in the reactions induced by the neutron-halo projectile and the corresponding same-mass stable projectile is a more favourable probe for extracting the information of σ1/NN(α) because of adding a new judgement.展开更多
Based on both very obvious isospin effect of the neutron-proton number ratio of nucleon emissions (n/p)nud on symmetry potential and (n/p)nucl's sensitive dependence on symmetry potential in the nuclear reactions...Based on both very obvious isospin effect of the neutron-proton number ratio of nucleon emissions (n/p)nud on symmetry potential and (n/p)nucl's sensitive dependence on symmetry potential in the nuclear reactions induced by halo-neutron projectiles, compared to the same mass stable projectile, probing symmetry potential is investigated within the isospin-dependent quantum molecular dynamics with isospin and momentum-dependent interactions for different symmetry potentials U;ym and U2^sym. It is found that the neutron-halo projectile induces very obvious increase of (n/p)nucl and strengthens the dependence of (n/p) l on the symmetry potential for all the beam energies and impact parameters, compared to the same mass stable projectile under the same incident channel condition. Therefore (n/p)nucl induced by the neutron-halo projectile is a more favourable probe than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential.展开更多
The effect of momentum-dependent interaction on the kinetic energy spectrum of the neutron-proton ratio ( (n/p)gas)b( Ek ) for 64Zn +64Zn is studied. It is found that ( (n/p)gas)b( Ek ) sensitively depend...The effect of momentum-dependent interaction on the kinetic energy spectrum of the neutron-proton ratio ( (n/p)gas)b( Ek ) for 64Zn +64Zn is studied. It is found that ( (n/p)gas)b( Ek ) sensitively depends on the momentumdependent interaction and weakly on the in-medium nucleon-nucleon cross section and symmetry potential. Therefore ( (n/p)gas)b( Ek ) is a possible probe for extracting information on the momentum-dependent interaction in heavy ion collisions.展开更多
基金Project supported by the State Key Development Program for Basic Research of China (Grant No G2000077400), the Major Program of the National Natural Science Foundation of China (Grant Nos 10435080 and 105350101), the National Natural Science Foundation of China (Grant Nos 10447006 and 10575075), the CAS Knowledge Innovation Project Program (Grant No KJCX2-SW-N02).
文摘Probing in-medium nucleon-nucleon (NN) cross section σ1/NN(α) in heavy ion collisions has been investigated by means of the isospin-dependent quantum molecular dynamics (IQMD) with the isospin- and momentum-dependent interaction (IMDI(T)). It is found that there are the very obvious medium effect and the sensitive isospin-dependence of nuclear stopping R on the in-medium NN cross section α1/NN(α) in the nuclear reactions induced by halo-neutron projectile and the same-mass stable projectile. However, R induced by the neutron-halo projectile is obviously lower than that induced by the corresponding stable projectile. In particular, there is a very obvious dependence of R on the medium effect of σ1/NN(α) in the whole beam energy region for the above two kinds of projectiles. Therefore, the comparison between the results of R's in the reactions induced by the neutron-halo projectile and the corresponding same-mass stable projectile is a more favourable probe for extracting the information of σ1/NN(α) because of adding a new judgement.
基金Supported by the State Key Basic Research and Development Programme of China under Grant No G2000077400, the National Natural Science Foundation of China under Grant Nos 10435080, 105350101, 10447006 and 10575075, the Knowledge Innovation Project of Chinese Academy of Sciences under Grant No KJCX2-SW-N02.
文摘Based on both very obvious isospin effect of the neutron-proton number ratio of nucleon emissions (n/p)nud on symmetry potential and (n/p)nucl's sensitive dependence on symmetry potential in the nuclear reactions induced by halo-neutron projectiles, compared to the same mass stable projectile, probing symmetry potential is investigated within the isospin-dependent quantum molecular dynamics with isospin and momentum-dependent interactions for different symmetry potentials U;ym and U2^sym. It is found that the neutron-halo projectile induces very obvious increase of (n/p)nucl and strengthens the dependence of (n/p) l on the symmetry potential for all the beam energies and impact parameters, compared to the same mass stable projectile under the same incident channel condition. Therefore (n/p)nucl induced by the neutron-halo projectile is a more favourable probe than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10435080(key project), 10575075 and 10905041, the Knowledge Innovation Project of Chinese Academy of Sciences under Grant Nos KJCX2-SW-N02.
文摘The effect of momentum-dependent interaction on the kinetic energy spectrum of the neutron-proton ratio ( (n/p)gas)b( Ek ) for 64Zn +64Zn is studied. It is found that ( (n/p)gas)b( Ek ) sensitively depends on the momentumdependent interaction and weakly on the in-medium nucleon-nucleon cross section and symmetry potential. Therefore ( (n/p)gas)b( Ek ) is a possible probe for extracting information on the momentum-dependent interaction in heavy ion collisions.