Dynamical dipole mode in heavy-ion collisions has been studied by using an isospin-dependent BoltzmannUehling-Uhlenbeck(IBUU) model. We investigate the dependence of centroid energy and strength of the γspectrum on b...Dynamical dipole mode in heavy-ion collisions has been studied by using an isospin-dependent BoltzmannUehling-Uhlenbeck(IBUU) model. We investigate the dependence of centroid energy and strength of the γspectrum on beam energy, N/Z ratio and mass asymmetry. The calculated yield and angular distribution of theγ-ray produced by dynamical dipole emission are consistent with the experimental data. The results show that the detailed study of dynamical dipole radiation can provide information on the isospin evolution of chargeasymmetric heavy-ion collisions around the normal nuclear density.展开更多
The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Ca...The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Carlo sample of e^+e^- collisions at a center-of-mass energy of4.26 or 4.6 Ge V, in the framework of the BESIII software system. The 90 % confidence level upper limits on B(τ^-→γμ^-) are estimated assuming no signal is produced. We also obtain the sensitivity on B(τ^-→γμ^-) as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34 ab^(-1) are needed to reach the current best upper limit of 4:4 10^(-8) and about 2510 ab^(-1) are needed to reach a sensitivity of 10^(-9) if the detector design is similar to that of BESIII.展开更多
基金Supported partially by the National Natural Science Foundation of China projects(Nos.11220101005,11035009,11175231 and 10979074)the Major State Basic Research Development Program in China(No.2013CB834405)the Knowledge Innovation Project of the Chinese Academy of Sciences(No.KJCX2-EW-N01)
文摘Dynamical dipole mode in heavy-ion collisions has been studied by using an isospin-dependent BoltzmannUehling-Uhlenbeck(IBUU) model. We investigate the dependence of centroid energy and strength of the γspectrum on beam energy, N/Z ratio and mass asymmetry. The calculated yield and angular distribution of theγ-ray produced by dynamical dipole emission are consistent with the experimental data. The results show that the detailed study of dynamical dipole radiation can provide information on the isospin evolution of chargeasymmetric heavy-ion collisions around the normal nuclear density.
基金the National Natural Science Foundation of China (11235011)the National Basic Research Program of China (2015CB856701)CAS Center for Excellence in Particle Physics (CCEPP)
文摘The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Carlo sample of e^+e^- collisions at a center-of-mass energy of4.26 or 4.6 Ge V, in the framework of the BESIII software system. The 90 % confidence level upper limits on B(τ^-→γμ^-) are estimated assuming no signal is produced. We also obtain the sensitivity on B(τ^-→γμ^-) as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34 ab^(-1) are needed to reach the current best upper limit of 4:4 10^(-8) and about 2510 ab^(-1) are needed to reach a sensitivity of 10^(-9) if the detector design is similar to that of BESIII.
