Tailward ion outflows in the Martian-induced magnetotail are known to be one of the major channels for Martian atmospheric escape.On the basis of nearly 6.5 years of observations from the Mars Atmosphere and Volatile ...Tailward ion outflows in the Martian-induced magnetotail are known to be one of the major channels for Martian atmospheric escape.On the basis of nearly 6.5 years of observations from the Mars Atmosphere and Volatile EvolutioN(MAVEN)mission,we investigate the statistical distribution of tailward and Marsward fluxes of heavy ions(i.e.,O^(+),and O_(2)^(+))in the near-Mars magnetotail and explore their characteristic responses to the corotating interaction region(CIR),solar wind dynamic pressure,and local magnetic field intensity.Our results show that the tailward fluxes of oxygen ions and molecular oxygen ions in the magnetotail are significantly greater than their Marsward fluxes and that the tailward flux of molecular oxygen ions is generally larger than that of oxygen ions.Furthermore,the tailward ion flux distribution exhibits dependence on the CIR,solar wind dynamic pressure,and local magnetic field strength in a manner stronger than the Marsward ion flux distribution.According to the distribution of tailward ion fluxes,we calculate the corresponding escape rates of heavy ions and show that when the CIR occurs,the total escape rates of oxygen ions and molecular oxygen ions increase by a factor of~2 and~1.2,respectively.We also find that the escape rates of heavy ions increase with the enhancement of solar wind dynamic pressure,whereas the overall effect of the local magnetic field is relatively weak.Our study has important implications for improved understanding of the underlying mechanisms responsible for the Martian atmospheric escape and the evolution of the Martian atmospheric climate.展开更多
We discuss the escape problem with the consideration of both the activity of particles and the roughness of potentials.We derive analytic expressions for the escape rate of an active Brownian particle in two types of ...We discuss the escape problem with the consideration of both the activity of particles and the roughness of potentials.We derive analytic expressions for the escape rate of an active Brownian particle in two types of rough potentials by employing the effective equilibrium approach and the Zwanzig method.We find that activity enhances the escape rate,but both the oscillating perturbation and the random amplitude hinder escaping.展开更多
This study investigates the diffusive motion of a Brownian particle in a 1D periodic potential. The reactive flux theory for finite barriers and memory friction is developed to calculate the escape rate in the spatial...This study investigates the diffusive motion of a Brownian particle in a 1D periodic potential. The reactive flux theory for finite barriers and memory friction is developed to calculate the escape rate in the spatial diffusion regime. The diffusion coefficient is obtained in terms of the jump-model. The theoretical results agree well with the Langevin simulation results. The method can be generalized to other colored noises with Gaussian distribution.展开更多
Phase transition is a core content of black hole thermodynamics. This study adopted Kramer’s escape rate method for describing the Brownian motion of particles in an external field to investigate the intensity of the...Phase transition is a core content of black hole thermodynamics. This study adopted Kramer’s escape rate method for describing the Brownian motion of particles in an external field to investigate the intensity of the phase transition between small and large black hole states. Some existing studies mostly focused on the formal analysis of the thermodynamic phase transition of black holes, but they neglected the detailed description of the phase transition process. Our results show that the phase transition between small and large black holes for charged anti-de Sitter(AdS) black holes presents serious asymmetric features, and the overall process is dominated by the transition from a small black hole to a large black hole. This study filled a research gap of a stochastic process analysis on the issue of the first-order phase transition rate in the Ad S black hole.展开更多
基金supported by the National Natural Science Foundation of China (grants 42025404, 42188101, 41904144, and 41674163)the preresearch projects on Civil Aerospace Technologies (grants D020303, D020104, and D020308)+2 种基金funded by the China National Space Administrationthe B-type Strategic Priority Program of the Chinese Academy of Sciences (grant XDB41000000)the Fundamental Research Funds for the Central Universities (grants 2042021kf1045 and 2042021kf1056)
文摘Tailward ion outflows in the Martian-induced magnetotail are known to be one of the major channels for Martian atmospheric escape.On the basis of nearly 6.5 years of observations from the Mars Atmosphere and Volatile EvolutioN(MAVEN)mission,we investigate the statistical distribution of tailward and Marsward fluxes of heavy ions(i.e.,O^(+),and O_(2)^(+))in the near-Mars magnetotail and explore their characteristic responses to the corotating interaction region(CIR),solar wind dynamic pressure,and local magnetic field intensity.Our results show that the tailward fluxes of oxygen ions and molecular oxygen ions in the magnetotail are significantly greater than their Marsward fluxes and that the tailward flux of molecular oxygen ions is generally larger than that of oxygen ions.Furthermore,the tailward ion flux distribution exhibits dependence on the CIR,solar wind dynamic pressure,and local magnetic field strength in a manner stronger than the Marsward ion flux distribution.According to the distribution of tailward ion fluxes,we calculate the corresponding escape rates of heavy ions and show that when the CIR occurs,the total escape rates of oxygen ions and molecular oxygen ions increase by a factor of~2 and~1.2,respectively.We also find that the escape rates of heavy ions increase with the enhancement of solar wind dynamic pressure,whereas the overall effect of the local magnetic field is relatively weak.Our study has important implications for improved understanding of the underlying mechanisms responsible for the Martian atmospheric escape and the evolution of the Martian atmospheric climate.
基金the National Natural Science Foundation of China(Grant No.11975050 and No.11735005)
文摘We discuss the escape problem with the consideration of both the activity of particles and the roughness of potentials.We derive analytic expressions for the escape rate of an active Brownian particle in two types of rough potentials by employing the effective equilibrium approach and the Zwanzig method.We find that activity enhances the escape rate,but both the oscillating perturbation and the random amplitude hinder escaping.
文摘This study investigates the diffusive motion of a Brownian particle in a 1D periodic potential. The reactive flux theory for finite barriers and memory friction is developed to calculate the escape rate in the spatial diffusion regime. The diffusion coefficient is obtained in terms of the jump-model. The theoretical results agree well with the Langevin simulation results. The method can be generalized to other colored noises with Gaussian distribution.
基金supported by the National Natural Science Foundation of China (Grant Nos. 12105222, 12275216, and 12247103)the Double First-class University Construction Project of Northwest University。
文摘Phase transition is a core content of black hole thermodynamics. This study adopted Kramer’s escape rate method for describing the Brownian motion of particles in an external field to investigate the intensity of the phase transition between small and large black hole states. Some existing studies mostly focused on the formal analysis of the thermodynamic phase transition of black holes, but they neglected the detailed description of the phase transition process. Our results show that the phase transition between small and large black holes for charged anti-de Sitter(AdS) black holes presents serious asymmetric features, and the overall process is dominated by the transition from a small black hole to a large black hole. This study filled a research gap of a stochastic process analysis on the issue of the first-order phase transition rate in the Ad S black hole.