MMS observations of flux rope formation and magnetic reconnection implications in Earth's central plasma sheet

Flux ropes resulting from magnetic reconnection in Earth's central plasma sheet are an integral part of planetary magnetotail dynamics. The launch of the Magnetospheric Multiscale (MMS) mission, with its tetrahedral configuration of satellites spaced only 20 km apart, has allowed for the study of the magnetotail flux ropes to occur at unprecedented precision, which offers the opportunity to better understand their formation in the plasma sheet. In this study, we identified both earthward and tailward traveling flux ropes using the high resolution magnetic field and plasma measurements observed by the MMS spacecraft during Phase 2b of the mission. The minimum variance analysis (MVA) technique was conducted on each identified flux rope event to ascertain its axis orientation. The force-free flux rope model fitting technique was then used to estimate the impact parameter for which the MMS encounters the flux rope, the strength of the axial core field, and the diameter of each flux rope. Statistical analysis was also conducted on the identified flux ropes to investigate the distribution of their physical (e.g. size) and plasma properties. Our results show that the flux ropes have an average radius of 0.7 R_E and average plasma velocity of 350 km/s. In addition to the analysis done on the flux ropes as individual events, we examined the spatial distribution of the Earthward and tailward flux rope occurrences to understand the nature of magnetic reconnection in Earth's central plasma sheet. Results of this study will be compared with the results from earlier flux rope studies using data from the THEMIS and Cluster missions. Furthermore, we will compare our results with observations of flux ropes in the magnetotails of other planets (e.g. Mercury).