*************************** ** THE GEM MESSENGER ** *************************** Volume 7, Number 15 May 12, 1997 ------------------------------------------ 1997 Snowmass Workshop: GEM T/S WG-1 PLANS ------------------------------------------ From: Larry Lyons (Larry at atmos.ucla.edu) 1997 SNOWMASS: TAIL/SUBSTORM CAMPAIGN WG 1: Workshop Schedule as of May 7 Last summer, our group planned a number of studies focused on defining an accurate spatial and temporal description of the substorm process in the magnetosphere and ionosphere. Below is a list of discussion topics for this summer's workshop based on responses to our previous requests. If you are doing work on these events and are not included in the schedule (and want to be included), please let us know. Please also lead us know about new ad-hoc events that you wish to discuss at this summer's workshop. WE HAVE THREE 2-hr SESSIONS PLANNED AS FOLLOWS: A. MONDAY 16 JUNE 10-12: Ad-hoc GEM intervals LUI: results from classic isolated substorm at 0430 UT on 9 Feb. 1995 with comprehensive ISTP observations (LUI): Apparently triggered by the IMF. WINGLEE: Model predictions for Lui event compared to IMP 8 and GEOTAIL observations on the nightside. RODGER: Nice isolated substorm of March 9, 1995, at 0248 UT with excellent ISTP data and a 1 hr and 20 min growth phase. (NO DISCUSSION PLANNED since Alan Rodger can not attend) SANCHEZ: Results from two ISTP events with good radar coverage, Sondrestrom imager data, and GEOTAIL in center of tail at 25 Re: Magnetosphere-ionosphere coupling of onsets to be studied. Onsets at ~2245 UT on 7 Feb. 1995, ~01 UT on 8 Feb. 1995, ~23 UT on 23 Feb. 1995, and ~0310 UT on 24 Feb. 1995 R. NAKAMURA: GEOTAIL tail response to the IMF and relationships to ground magnetogram disturbance for the isolated substorm onsets 1108 and 1502 UT on Nov. 22, 1995. New Ad Hoc events LYONS: GEOTAIL-CANOPUS conjunctions SANCHEZ - Discussion of new period on Sept. 9 and 10th, 1996. Particular times of interest are from 0000 to 0400 UT on the 10th with onset at 0207 UT. Others??? **PLEASE LET US KNOW** B. MONDAY 16 JUNE 3:30-5:30 p.m.: GEM intervals during WIND perigee passes. The following lists significant events detected on WIND during these intervals. 1. September 16, 1995: WIND B-field dipolarizations at X = -13 Re during 2200 - 2400 UT substorm. GEOTAIL observing IMF. Good Sondrestrom measurements of expansion into the polar cap. 2. November 28-29, 1995: WIND B-field dipolarizations at X = -12 Re during 0030, 0630 and 0740 UT substorms on the 29th. GEOTAIL at the dawn magnetopause/magnetosheath. Good Greenland data for first event. IMP-8 IMF. 3. January 13, 1996: WIND B-field dipolarization at X = -11 to -12 Re during 0300 and 1530 UT substorms. GEOTAIL skimming the dayside magnetosphere. First event has multiple injections. SuperDARN data good for entire period. Greenland data good. Effects seen at INTERBALL. Day-night comparisons on second substorm. 4. March 27, 1996: WIND and GEOTAIL B-field dipolarization at X = -15 Re and -18 Re respectively during 0940 UT substorm. INTERBALL in solar wind. POLAR imaging. 0925 pseudobreakup followed by big breakup at 0945. Also events at 2200 to 0300 on the 28th. 5. April 18, 1996: WIND and GEOTAIL B-field dipolarizations at X = -12 and -14 Re during substorms at 0500, 0730, and 1030 UT. Separation of 1 Re in X and Z and 10 Re in Y. INTERBALL and IMP in solar wind. Optical aurora equatorward of L = 4 in S Hem. 6. May 10, 1996: WIND B-field dipolarization at X = -12 Re during 0400 substorm. GEOTAIL in dayside magnetosphere. Apparently no solar wind data (IMP data gap). GOES dipolarization at 2300 local. 0400 injection at geosync. 0359 onset in POLAR images. INTERBALL 0400 magnetopause crossing. Good radar data. The following lead investigators for each numbered event were identified along with the events (topics) on which they will concentrate. SLAVIN (MAYNARD) - 5 SANCHEZ - 1 SANCHEZ/PARKS - 6 ANGELOPOULOS - 4 GREENWALD/BAKER - 6 MCPHERRON - 2: Approximate onset times 0353, 0736, 0842, 0931, 1117, 1248, 1520, 1915 on the 28th; 0010, 0601, 0730, 1210, 1510 on the 29th. Input solicited on any of these substorms, particularly on precise onset determination. C. TUESDAY 17 JUNE 10-11:15 am: New event January 1,2, 1997 GEOTAIL and IMP crossing midnight together ~8 Re apart at 30 Re. Weak activity. 3 small substorms near ~2300, 0200 and 0600. Please bring appropriate data for a workshop discussion on these events. From past experience, overview plots are nice for context but 2 hour plots are especially useful for data comparison and event analysis. We are particularly interested in data that can pinpoint ground onset in addition to satellite and other ground data. Discussion to be lead by MAYNARD/FOX/LUI, PARTICIPATION OF OTHERS REQUESTED D. TUESDAY 17 JUNE 11:15 am-noon: Plans for coordinated observations for next year, and wrap-up _____________________________ Nelson Maynard (nmaynard at mrcnh.com) Larry Lyons (Larry at atmos.ucla.edu) +-------------------------------------------------------------------------+ |To add name to the mailing list, send a message to: editor at igpp.ucla.edu | |For message to whole GEM mailing list, send to: gem at igpp.ucla.edu | | | |URL of GEM Home Page: http://igpp.ucla.edu/gem/Welcome.html | |Please update your e-mail address. | |CAUTION: Do not send messages to gem at igpp.ucla.edu unless you want | | your message to go to everyone in the GEM mailing list! | +-------------------------------------------------------------------------+