HR: 1340h
AN: SH13A-0280 [Abstracts]
TI: Flare Prediction and the Unresolved Corona
AU: * Weber, M
EM: mweber@cfa.harvard.edu
AF: SAO / CfA, 60 Garden St, MS-58, Cambridge, MA 02138
United States
AU: Cirtain, J
EM: jcirtain@cfa.harvard.edu
AF: SAO / CfA, 60 Garden St, MS-58, Cambridge, MA 02138
United States
AU: Martens, P
EM: martens@solar.physics.montana.edu
AF: Montana State Univ., PO Box 173840, Bozeman, MT 59717-3840
United States
AB:
Discovery of the precursors to flare onset are paramount to the increased need for accurate space weather prediction. A
potential indicator for flaring activity may be the temperature structure of the active region background emission. The
active region background, or unresolved active region corona (UARC), can be modeled using a hydrostatic model for the density
stratification as a function of altitude. Exponential decreases in the intensity of EUV emission above the limb and within
active regions have been used to determine the scale-height temperature of the UARC. ``Quiescent'' active region data was
examined, and the scale-height temperature determined was found to be constant in time and slowly decreasing with distance
from the center of the active region. ``Flaring'' active region emission was found to be quite different. Prior to the onset
of the flare, the estimated scale height temperature was nearly constant. Just before the peak in the GOES 8 x-ray flux, it
was determined to be multithermal, varying by as much as 0.7 MK over the multiple spectral lines observed. The scale-height
temperatures were all observed to increase before the flare and reached a maximum subsequent to the GOES 8 x-ray
peak.This work is supported under the TRACE mission, NASA contract SP02H8201R.
DE: 7509 Corona
DE: 7519 Flares
DE: 7594 Instruments and techniques
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005