Measurements of convection electric field in the inner magnetosphere

In this paper, we study the characteristic of large-scale convection electric field in the inner magnetosphere, using magnetospheric multiscale(MMS) observations between L=5 and L=8 over the period from September 1, 2015 to October 31, 2016,covering almost all magnetic local time(MLT). Observations show that the DC convection electric field generally has small variations in this region. We investigate whether the convection electric field is correlated with geomagnetic indices and solar wind parameters. It is found that, among the studied parameters, solar wind electric field, z component of interplanetary magnetic field, AE and Kp indices show good correlations with the averaged convection electric field. The results in this paper provide valuable information for understanding the role of electric field on the dynamics of the inner magnetosphere.