A preliminary model is proposed to describe quantitatively the position and movement of cusp equatorward boundary. This integrated model, consisting of an empirical model of the magnetopause and a compressed dipolar m...A preliminary model is proposed to describe quantitatively the position and movement of cusp equatorward boundary. This integrated model, consisting of an empirical model of the magnetopause and a compressed dipolar model of Open/Closed field line, connects quantitatively the solar wind conditions, subsolar magnetopause and cusp equatorward boundary. It is shown that the increasing solar wind dynamic pressure and the increasing southward Interplanetary Magnetic Field (IMF) component drive the magnetopause to move inward and the cusp equatorward. This model is adopted to interpret quantitatively the cusp movement of August 14, 2001 observed by Cluster. The results show that the subsolar magnetopause moved earthward from 10.7 Re to 9.0Re during the period of 002300-002800 UT, and correspondingly the cusp equatorward boundary shifted equatorward. The observations of Cluster C1 and C4 show the cusp equatorward boundary that Cluster C1 and C4 were crossing during same interval moved equatorward by 4.6°. The cusp equatorward boundary velocity computed in the theoretical model (10.7 km/s) is in good agreement with the observed value(9.4km/s) calculated from the data of CIS of Cluster C4 and C1.展开更多
When the IMF turns southward, a great amount of magnetic energy is stored in the magnetotail, and the electric field across the magnetotail substantially en-hances. As long as magnetic reconnection (MR) in the mag-net...When the IMF turns southward, a great amount of magnetic energy is stored in the magnetotail, and the electric field across the magnetotail substantially en-hances. As long as magnetic reconnection (MR) in the mag-netotail initiates and continues, the magnetic field and plasma in the central plasma sheet are carried away to the near-Earth and down to the tail, the magnetic field and plasma in the lobe region enter the CPS and are involved in MR. We call this process “Continuous Lobe Reconnection (CLR)”. In this paper a detailed analysis of Cluster observa-tion of MR through 2001―2003 is made. Plenty of CLR events are found that led to considerable changes of tail con-figuration, appearance of BBF, as well as large-scale bubbles in which both plasma temperature and number density sub-stantially decrease. It is shown that in general CLR events last for dozens of minutes and have good correspondence to substorm initiation under the condition of continuous southward IMF.展开更多
基金Supported by NSFC (No. 40474062)the China-Russia Joint Research Center on Space Weather,Chinese Academy of Sciences,Key Lab for Space weather, CSSAR
文摘A preliminary model is proposed to describe quantitatively the position and movement of cusp equatorward boundary. This integrated model, consisting of an empirical model of the magnetopause and a compressed dipolar model of Open/Closed field line, connects quantitatively the solar wind conditions, subsolar magnetopause and cusp equatorward boundary. It is shown that the increasing solar wind dynamic pressure and the increasing southward Interplanetary Magnetic Field (IMF) component drive the magnetopause to move inward and the cusp equatorward. This model is adopted to interpret quantitatively the cusp movement of August 14, 2001 observed by Cluster. The results show that the subsolar magnetopause moved earthward from 10.7 Re to 9.0Re during the period of 002300-002800 UT, and correspondingly the cusp equatorward boundary shifted equatorward. The observations of Cluster C1 and C4 show the cusp equatorward boundary that Cluster C1 and C4 were crossing during same interval moved equatorward by 4.6°. The cusp equatorward boundary velocity computed in the theoretical model (10.7 km/s) is in good agreement with the observed value(9.4km/s) calculated from the data of CIS of Cluster C4 and C1.
基金supported by the N ational Natural Science Foundation of China major program(Grant No.40390152)the State Key Basic Research Program(Grant No.G200000784)+2 种基金the XK 100010404 of Beijing Citythe Space Weather LaboratoryCenter for Space Science and Applied Research.CAS.
文摘When the IMF turns southward, a great amount of magnetic energy is stored in the magnetotail, and the electric field across the magnetotail substantially en-hances. As long as magnetic reconnection (MR) in the mag-netotail initiates and continues, the magnetic field and plasma in the central plasma sheet are carried away to the near-Earth and down to the tail, the magnetic field and plasma in the lobe region enter the CPS and are involved in MR. We call this process “Continuous Lobe Reconnection (CLR)”. In this paper a detailed analysis of Cluster observa-tion of MR through 2001―2003 is made. Plenty of CLR events are found that led to considerable changes of tail con-figuration, appearance of BBF, as well as large-scale bubbles in which both plasma temperature and number density sub-stantially decrease. It is shown that in general CLR events last for dozens of minutes and have good correspondence to substorm initiation under the condition of continuous southward IMF.
