Solar Flare Physics in the RHESSI Era

Report from the First Workshop

Berkeley, CA, October 17-20, 2002

Gordon Emslie, Workshop Convener (gordon.emslie@okstate.edu)

Background

The purpose of the RHESSI workshop series is to bring together scientists to explore current topics in solar flare physics in a coordinated manner. The emphasis is on topics that can be addressed with the RHESSI mission, launched on February 5, 2002. For more details on the RHESSI mission, see the sites at http://hessi.ssl.berkeley.edu/ and http://hesperia.gsfc.nasa.gov/hessi/.

The workshop series consists of a series of general workshops, held approximately annually. Workshop participants have been organized into working groups, with each team aimed at addressing specific problems in high-energy solar flare physics. The four teams, and the respective team leaders, are as follows:

Topic	Team Leader	e-mail
Electron Acceleration and Propagation	David Alexander	alexander@lsmal.com
Ion Acceleration and Interaction	Jim Milller	millerja@uah.edu
Correlative Studies between Hard X-Ray and Radio	Stephen White	white@astro.umd.edu
Multiwavelength Correlative Studies	Lyndsay Fletcher	lyndsay@astro.gla.ac.uk

The first general workshop was held from October 17-20, 2002, at the Space Science Laboratory of the University of California, Berkeley. Topics covered by the various teams included:

Electron acceleration and propagation – location and spectrum of accelerated electrons, physics of electron transport, interpretation of RHESSI spectroscopy, imaging spectroscopy and polarization data.

Ion acceleration and interaction – location, energy and angular spectra of accelerated ions, interaction with solar atmosphere, abundance determination and related physics.

Correlative Studies between Hard X-ray and Radio – synthesis and intercomparison of hard X-ray and radio data (e.g., spectra, images, temporal profiles) in order to identify issues pertinent to electron acceleration and transport.

Multiwavelength Correlative Studies – Synthesis of data from a wide range of observatories (optical, ultraviolet) with RHESSI data to obtain a comprehensive picture of the flare and its environment.

The presentations made by the various working groups may be found at the following websites:

Group 1:

http://www.lmsal.com/~alexande/RHESSI/

Group 2: This group is focusing attention on the July 23, 2002 X-class flare, which produced gamma-ray line and continuum spectra of unprecedented quality. A series of papers is being prepared for a special issue of The Astrophysical Journal (Letters), to be published in early 2003.

Group 3:

http://sprg.ssl.berkeley.edu/RHESSI/rhessi_workshop/WG3/

Group 4:

http://sprg.ssl.berkeley.edu/RHESSI/rhessi_workshop/WG4/

Papers covering some of the material presented at the workshop will appear in the November 2002 issue of Solar Physics, and can be found in the Max Millennium e-print archive at

http://solar.physics.montana.edu/cgi-bin/eprint/default_page.pl

A “general” workshop will be scheduled approximately every year, with smaller “topical” workshops interspersed. The schedule for both the general and topical workshops may be found at:

http://www.gradcollege.okstate.edu/rhessi_workshops/workshop_schedule.htm