Empirical Modeling of Magnetotail Reconnection

Monday, 15 December 2014
Kevin James Genestreti1, Stephen Fuselier1, Jerry Goldstein1, Tsugunobu Nagai2 and Jonathan P Eastwood3, (1)Southwest Research Institute San Antonio, San Antonio, TX, United States, (2)Tokyo Institute of Technology, Tokyo, Japan, (3)Imperial College London, London, United Kingdom
We present results of an empirical model of magnetotail reconnection, and examine empirical evidence constraining its cross-tail scale size. An empirical model for the location and rate of occurrence of the nightside near-Earth reconnection site is calculated as a function of both XGSM and YGSM from Cluster and Geotail observations. We find that the rate of occurrence of the ion-electron decoupling region is localized in YGSM and biased towards dusk. We update our empirical model to reflect the updated predicted ephemeris for the upcoming NASA Magnetospheric MultiScale (MMS) mission. Despite the recent change in the launch date of MMS, the predicted number of instances where MMS will encounter the reconnection region does not change from our previously determined value of 11±4. To lay the groundwork for further empirical modeling that accounts for the shape of the YGSM-dependent occurrence rate and estimates the cross-tail scale size, we analyze in situ observations of the reconnection region. Initial results constraining the cross-tail scale of an extended X-line, and the driving conditions that govern it, are presented.