Common-track constellation is a special kind of constellation, all ground tracks of satellites are in one track. With recursive orbit or quasi-recursive orbit, the ground track of the constellation is a closed loop wi...Common-track constellation is a special kind of constellation, all ground tracks of satellites are in one track. With recursive orbit or quasi-recursive orbit, the ground track of the constellation is a closed loop with a repeating track. In particular, if the constellation is in one orbit plane, the constellation can meet the requirement for a multi-satellite launch mission and fast satellite-satellite link establishment. The characteristics and coverage properties of a common-track constellation in one orbit plane are studied in this paper. The simulation results show that a common-track constellation in one orbit plane can provide favorable coverage to a target station in the polar areas.展开更多
We studied the system of pure Rashba spin–orbit coupled Bose gas with an in-plane magnetic field. Based on the mean field theory, we obtained the zero temperature phase diagram of the system which exhibits three phas...We studied the system of pure Rashba spin–orbit coupled Bose gas with an in-plane magnetic field. Based on the mean field theory, we obtained the zero temperature phase diagram of the system which exhibits three phases, plane wave（PW） phase, striped wave（SW） phase, and zero momentum（ZM） phase. It was shown that with a growing in-plane field,both SW and ZM phases will eventually turn into the PW phase. Furthermore, we adopted the Bogoliubov theory to study the excitation spectrum as well as the sound speed.展开更多
We study theoretically the influence of spin-orbit coupling induced by in-plane external electric field on the intrinsic spin-Hall effect in a two-dimensional electron gas with Rashba spin-orbit coupling. We show that...We study theoretically the influence of spin-orbit coupling induced by in-plane external electric field on the intrinsic spin-Hall effect in a two-dimensional electron gas with Rashba spin-orbit coupling. We show that, after such an influence is taken into account, the static intrinsic spin-Hall effect can be stabilized in a disordered Rashba twodimensional electron gas, and the static intrinsic spin-Hall conductivity shall exhibit some interesting characteristics as conceived in some original theoretical proposals.展开更多
The high-intensity heavy-ion accelerator facility(HIAF)is under design at the Institute of Modern Physics(IMP)and will provide an intense ion beam for nuclear physics,atomic mass measurement research,and other applica...The high-intensity heavy-ion accelerator facility(HIAF)is under design at the Institute of Modern Physics(IMP)and will provide an intense ion beam for nuclear physics,atomic mass measurement research,and other applications.As the main ring of HIAF,the BRing accumulates beams to high intensity and accelerates them to high energy.To achieve high intensities up to 1×10^(11)(^(238)U^(34+)),the injection gain of the BRing must be as high as 88.However,multiple multiturn injection supported by the electron cooling system takes a long time,causing substantial beam loss under a strong space charge effect.Hence,a two-plane painting injection scheme is proposed for beam accumulation in the BRing.This scheme uses a tilted injection septum and horizontal and vertical bump magnets to paint the beam into horizontal and vertical phase space simultaneously.In this paper,the two-plane painting injection parameters are optimized,and the resulting injection process is simulated using the Objective Ring Beam Injection and Tracking(ORBIT)code.An injection gain of up to 110.3 with a loss rate of 2:3%is achieved,meeting the requirements of BRing.展开更多
The so-called “global polytropic model” is based on the assumption of hydrostatic equilibrium for the solar system, or for a planet’s system of statellites (like the Jovian system), described by the Lane-Emden diff...The so-called “global polytropic model” is based on the assumption of hydrostatic equilibrium for the solar system, or for a planet’s system of statellites (like the Jovian system), described by the Lane-Emden differential equation. A polytropic sphere of polytropic index?n?and radius?R1?represents the central component?S1?(Sun or planet) of a polytropic configuration with further components the polytropic spherical shells?S2,?S3,?..., defined by the pairs of radi (R1,?R2), (R2,?R3),?..., respectively.?R1,?R2,?R3,?..., are the roots of the real part Re(θ) of the complex Lane-Emden function?θ. Each polytropic shell is assumed to be an appropriate place for a planet, or a planet’s satellite, to be “born” and “live”. This scenario has been studied numerically for the cases of the solar and the Jovian systems. In the present paper, the Lane-Emden differential equation is solved numerically in the complex plane by using the Fortran code DCRKF54 (modified Runge-Kutta-Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane along complex paths). We include in our numerical study some trans-Neptunian objects.展开更多
文摘Common-track constellation is a special kind of constellation, all ground tracks of satellites are in one track. With recursive orbit or quasi-recursive orbit, the ground track of the constellation is a closed loop with a repeating track. In particular, if the constellation is in one orbit plane, the constellation can meet the requirement for a multi-satellite launch mission and fast satellite-satellite link establishment. The characteristics and coverage properties of a common-track constellation in one orbit plane are studied in this paper. The simulation results show that a common-track constellation in one orbit plane can provide favorable coverage to a target station in the polar areas.
基金Project supported by the National Natural Science Foundation of China(Grant No.10774088)
文摘We studied the system of pure Rashba spin–orbit coupled Bose gas with an in-plane magnetic field. Based on the mean field theory, we obtained the zero temperature phase diagram of the system which exhibits three phases, plane wave（PW） phase, striped wave（SW） phase, and zero momentum（ZM） phase. It was shown that with a growing in-plane field,both SW and ZM phases will eventually turn into the PW phase. Furthermore, we adopted the Bogoliubov theory to study the excitation spectrum as well as the sound speed.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10874049)the State Key Program for Basic Research of China (Grant No. 2007CB925204)the Natural Science Foundation of Guangdong Province of China (GrantNo. 07005834)
文摘We study theoretically the influence of spin-orbit coupling induced by in-plane external electric field on the intrinsic spin-Hall effect in a two-dimensional electron gas with Rashba spin-orbit coupling. We show that, after such an influence is taken into account, the static intrinsic spin-Hall effect can be stabilized in a disordered Rashba twodimensional electron gas, and the static intrinsic spin-Hall conductivity shall exhibit some interesting characteristics as conceived in some original theoretical proposals.
基金supported by the National Natural Science Foundation of China(No.11505256)
文摘The high-intensity heavy-ion accelerator facility(HIAF)is under design at the Institute of Modern Physics(IMP)and will provide an intense ion beam for nuclear physics,atomic mass measurement research,and other applications.As the main ring of HIAF,the BRing accumulates beams to high intensity and accelerates them to high energy.To achieve high intensities up to 1×10^(11)(^(238)U^(34+)),the injection gain of the BRing must be as high as 88.However,multiple multiturn injection supported by the electron cooling system takes a long time,causing substantial beam loss under a strong space charge effect.Hence,a two-plane painting injection scheme is proposed for beam accumulation in the BRing.This scheme uses a tilted injection septum and horizontal and vertical bump magnets to paint the beam into horizontal and vertical phase space simultaneously.In this paper,the two-plane painting injection parameters are optimized,and the resulting injection process is simulated using the Objective Ring Beam Injection and Tracking(ORBIT)code.An injection gain of up to 110.3 with a loss rate of 2:3%is achieved,meeting the requirements of BRing.
文摘The so-called “global polytropic model” is based on the assumption of hydrostatic equilibrium for the solar system, or for a planet’s system of statellites (like the Jovian system), described by the Lane-Emden differential equation. A polytropic sphere of polytropic index?n?and radius?R1?represents the central component?S1?(Sun or planet) of a polytropic configuration with further components the polytropic spherical shells?S2,?S3,?..., defined by the pairs of radi (R1,?R2), (R2,?R3),?..., respectively.?R1,?R2,?R3,?..., are the roots of the real part Re(θ) of the complex Lane-Emden function?θ. Each polytropic shell is assumed to be an appropriate place for a planet, or a planet’s satellite, to be “born” and “live”. This scenario has been studied numerically for the cases of the solar and the Jovian systems. In the present paper, the Lane-Emden differential equation is solved numerically in the complex plane by using the Fortran code DCRKF54 (modified Runge-Kutta-Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane along complex paths). We include in our numerical study some trans-Neptunian objects.
