# **WG1 + WG2 Joint Session Summary Tues 3/15/05**

**Science Topics**:

**Radiation belt:**

3\. What are solar wind conditions leading to cutoff reduction and
trapping of Solar Energetic Particles, and solar wind plus
magnetospheric conditions leading to loss? Examples are Nov. 6 and Nov.
24 2001 SEP trapping events of \> 12 MeV protons (and heavy ions) in the
electron slot region L=2.5 - 3, and sudden loss Nov. 20 2003. WG1
overlap. Hudson discussed SEP trapping obs and modelling for Nov 24 01,

Richardson discussed Nov 06 and 24 01 trapping; loss Nov 20 2003.

2\. What solar drivers/solar wind conditions lead to electron flux
enhancements as well as losses, esp. the deep dropouts (to L2 or so)
that appear associated with large storms. What are the processes
responsible for each? Webb and Braughtigam:

Comparing Deep Dropouts of Relativistic Electron Fluxes with Geomagnetic
Storms and Coronal Mass Ejections -- Nov 20 2003 storm was presented.

1\. Which solar wind drivers are most geoeffective at radiation belt
electron enhancements: high speed solar wind streams, CIRs, CMEs
including magnetic cloud and shock categories? Hudson, Baker led some
discussion.

Sub-question: How important is pre-conditioning of the magnetosphere?
e.g. elapsed time since previous storm, plasma sheet density, etc.? WG1
& 4 overlap.

**Need to include high speed stream intervals, as well as CMEs**.

**Ring current:**

4\. What is the relative importance of the solar-wind driven enhanced
magnetospheric convection electric field, variations in the plasma sheet
population, and the penetration electric field (SAPs) on storm-time ring
current development? WG1 & WG3 overlap

(Wygant E-fields), Siscoe sw density and plasmasheet source of ring
current, brief discussion.

**Defining and Measuring geoeffectiveness**

Vassiliades summary:

Response of RB electron flux to Vsw

Sampex and Polar correlation, lag time

P1 peaks L \~ 4-7 due to high speed streams, 2+ day lag

P2 peaks L\~2-4 due to CMEs, prompt

Different drivers  different trapping response time and location

Complex event with high speed stream + CME

June 18 2003 has hs stream back, ICME front, extended Bz south

Oct 30 2003 Bz south in sheath and ejecta, single full halo CME, 6^th^
fastest shock in history from travel time, 19 hrs

**WG2 events that WG1 may be interested in:**

**#27 16 July 2000 Good CAMMICE in im; sq \# 5, WG3 overlap**

**ULF wave data, good LANL coverage,IMAGE**

**#28-29 11-12 Aug 2000 Good CAMMICE in im, CEASE, HENA; no**

**SEP, enhancement of energetic el, sq #6**

**#33 29 Oct 2000 Good Polar/CAMMICE, HENA, EUV, sq #6**

**\# 37 31 Mar 2001 Superstorm weak RB, strong RC, WG3 overlap**

**#45 (21-23 Oct 2001) HENA, good Polar EFI**

#47 6 Nov 2001 CLUSTER in p.s., SEP trapping, rb model results

\# 48 24 Nov 2001 SEP trapping, rb and ring current model results

**\*#50-51 18-20 Apr 2002 Good CAMMICE in p.s., EUV, HENA,**

**CLUSTER in i.m. in rec. phase; sq #5, WG3**

**#58-60 1 Oct 2002 Good CEASE, HENA, CLUSTER in i.m. in**

**rec. phase; no SEP, enhancement of energetic el**

**\*#68-69 30 Oct 2003 Good CEASE, EUV; SEP, CLUSTER in**

**recovery phase; Superstorm, sq \# 5 WG3 overlap**

**\*#70 20 Nov 2003 Good EUV, CLUSTER in ps; largest \|Dst\|,**

**abrupt deep loss of energetic e-, sq \# 5, WG3**

**\*#74-76 27 July 2004 Good CEASE, CLUSTER in ps; no SEP,G/HEO**

**e- hi**

**\*#78-79 08 Nov 2004 Good CEASE, EUV, G/HEO e- hi**