This paper presents a study on potential instability and spiral structure of unstable rain clusters.First,we develop a linearized non-axisymmetrical mathematic model for rain clusters in circular cylindrical coordinat...This paper presents a study on potential instability and spiral structure of unstable rain clusters.First,we develop a linearized non-axisymmetrical mathematic model for rain clusters in circular cylindrical coordinates and acquire its analytic solution.Second,we discuss the potential instability of non-axisymmetrical rain clusters.Finally,we conclude that spiral structures can exist in rain clusters.Our analysis indicates that potential instability occurs when humid stratification coefficient is less than zero.Unstable growth rate increases with the increase of the absolute value for humid stratification coefficient.The simpler the vertical structure of perturbation,the thicker the inversion layer;additionally,the smaller the radius of the rain clusters,the larger the unstable growth rate.Simulation results agree well with those from observation and forecast.The spiral structure simulated by our model is similar to a radar echo,suggesting that rain clusters with spiral structures can occur in the atmosphere.In addition,they are generally close to the model solution in this work.展开更多
Using a microscopic four-body cluster model,we investigate the spectral properties and structural configurations of the ^(10)Be nucleus.We calculate physical quantities such as the root-mean-squared(r.m.s.)radii and e...Using a microscopic four-body cluster model,we investigate the spectral properties and structural configurations of the ^(10)Be nucleus.We calculate physical quantities such as the root-mean-squared(r.m.s.)radii and electromagnetic transition strengths.The theoretical results for the energies and certain electromagnetic transition strengths of the low-lying states show good agreement with experimental data.In particular,the enhancement of the r.m.s.radius and isoscalar monopole transition strength of the O_(3)^(+) state indicates a well-developed cluster structure.We obtained three 1-states in E_(x)<15 MeV that show remarkable dipole transition strengths,suggesting that the 1-states may have cluster structure.Using the obtained wave functions,we calculate the reduced-width amplitudes(RWAs)to investigate the SHe+α and'Be+n two-body cluster structures in ^(10)Be.The results suggest that the lowlying states show the two-body ^(6)He+α and ^(9)Be+n configuration,with the ^(6)He+α components of the two-body structure diminishing as the energy increases,which due to the breakup of He and ^(9)Be at higher excitation energies.Moreover,a few states above the α+α+n+n threshold still exhibit significant 9Be+n components.展开更多
基金National Natural Science Foundation of China.(4097503141005074)
文摘This paper presents a study on potential instability and spiral structure of unstable rain clusters.First,we develop a linearized non-axisymmetrical mathematic model for rain clusters in circular cylindrical coordinates and acquire its analytic solution.Second,we discuss the potential instability of non-axisymmetrical rain clusters.Finally,we conclude that spiral structures can exist in rain clusters.Our analysis indicates that potential instability occurs when humid stratification coefficient is less than zero.Unstable growth rate increases with the increase of the absolute value for humid stratification coefficient.The simpler the vertical structure of perturbation,the thicker the inversion layer;additionally,the smaller the radius of the rain clusters,the larger the unstable growth rate.Simulation results agree well with those from observation and forecast.The spiral structure simulated by our model is similar to a radar echo,suggesting that rain clusters with spiral structures can occur in the atmosphere.In addition,they are generally close to the model solution in this work.
文摘Using a microscopic four-body cluster model,we investigate the spectral properties and structural configurations of the ^(10)Be nucleus.We calculate physical quantities such as the root-mean-squared(r.m.s.)radii and electromagnetic transition strengths.The theoretical results for the energies and certain electromagnetic transition strengths of the low-lying states show good agreement with experimental data.In particular,the enhancement of the r.m.s.radius and isoscalar monopole transition strength of the O_(3)^(+) state indicates a well-developed cluster structure.We obtained three 1-states in E_(x)<15 MeV that show remarkable dipole transition strengths,suggesting that the 1-states may have cluster structure.Using the obtained wave functions,we calculate the reduced-width amplitudes(RWAs)to investigate the SHe+α and'Be+n two-body cluster structures in ^(10)Be.The results suggest that the lowlying states show the two-body ^(6)He+α and ^(9)Be+n configuration,with the ^(6)He+α components of the two-body structure diminishing as the energy increases,which due to the breakup of He and ^(9)Be at higher excitation energies.Moreover,a few states above the α+α+n+n threshold still exhibit significant 9Be+n components.