*************************** ** THE GEM MESSENGER ** *************************** Volume 14, Number 43 October 24, 2004 ------------------------------------------------------------------------- GEM GI Campaign at Fall AGU ------------------------------------------------------------------------- From: D. G. Sibeck There will be a mini-GEM workshop in San Francisco on December 12, 2004, the day before the Fall AGU. Although the exact location and times of this workshop have yet to be determined (see http://gem.rice.edu/~gem/ for further details), the Global Interactions Campaign has selected four events for intense discussion. The events focus upon the entry of plasma into the magnetosphere and the formation of the plasma sheet, particularly during periods of northward IMF orientation. Those interested in participating are hereby invited to bring observations, simulation results, and opinions to the workshop. The events selected for discussion are: 15 March 2002: 2200 UT to 16 March 2002 1100 UT. Wind observes a southward turning following a long interval of northward IMF. Cluster traverses the high-altitude cusp and magnetopause, Polar observes the dayside magnetopause, Geotail observes the nightside magnetotail and flanks, and Geotail and LANL geosynchronous spacecraft observe the nightside magnetosphere. The array of spacecraft can be used to track solar wind penetration and transport into the magnetosphere during intervals of northward IMF orientation and for studies of the effect of an abrupt southward turning of the IMF. Discussion leaders are Benoit Lavraud (lavraud@lanl.gov) and Jean Berchem (jberchem@igpp.ucla.edu). 18 April 2002 from 1600 to 1900 UT. Cluster sees a triple cusp encounter. ACE provides solar wind observations. Simulation results indicate that the magnetopause was observed in an unusual location. The Cluster observations have been interpreted as evidence for the cusp being blown about by variations in the solar wind flow direction. Discussion leaders are Q.-G. Zong (zong@bu.edu) and Jean Berchem (jberchem@igpp.ucla.edu). 22-24 October 2003. Following an interval of southward IMF, the IMF stayed almost purely northward for more than 30 hours. Cluster observed the cold-dense plasma sheet throughout the entire northward IMF interval. The transition from a hot-tenuous to a cold-dense plasma sheet was gradual and took ~4 hours following the northward IMF turning. DMSP observed the plasma sheet to be cold and dense at all local times. FAST observed signatures of poleward-of-the-cusp reconnection. Simulation results suggest that reconnection in the northern and southern cusps produced the cold-dense plasma sheet. There is a need to test this conclusion with other simulations. Discussion leaders are T.-D. Phan (phan@ssl.berkeley.edu) and Jimmy Raeder (jraeder@unh.edu) 24-25 October 2003. A long interval of generally northward IMF, is followed by a turning to purely IMF By and then southward. Cluster and Geotail observe a transition from cold and dense to to hot and tenuous plasma sheet parameters at different times, which provides an important constraint on models. Discussion leaders are Marit Oieroset (Oieroset@salsa.ssl.berkeley.edu) and Jimmy Raeder (jraeder@unh.edu). Those interested in discussing other events or phenomena should contact Campaign Coordinators David Sibeck (david.g.Sibeck@nasa.gov) or Tai Phan (phan@ssl.berkeley.edu) prior to the meeting. +-------------------------------------------------------------------------+ |To subscribe GEM Messengers, send an e-mail to | | with the following command in the body of your e-mail message: | | subscribe gem | |To remove yourself from the mailing list, the command is: | | unsubscribe gem | | | |To broadcast a message to the GEM community, please contact Peter Chi at | | | |Please use plain text as the format of your submission. | | | |URL of GEM Home Page: http://www-ssc.igpp.ucla.edu/gem/Welcome.html | |Workshop Information: http://gem.rice.edu/~gem | +-------------------------------------------------------------------------+