Trace and Yohkoh observations of high-temperature plasma in a two-ribbon limb flare

Citation
Hp. Warren et al., Trace and Yohkoh observations of high-temperature plasma in a two-ribbon limb flare, ASTROPHYS J, 527(2), 1999, pp. L121-L124
Citations number
17
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
527
Issue
2
Year of publication
1999
Part
2
Pages
L121 - L124
Database
ISI
SICI code
0004-637X(199912)527:2<L121:TAYOOH>2.0.ZU;2-T
Abstract
The ability of the Transition Region and Coronal Explorer (TRACE) to image solar plasma over a wide range of temperatures (T-e similar to 10(4)-10(7) K) at high spatial resolution (0 ".5 pixels) makes it a unique instrument f or observing solar flares. We present TRACE and Yohkoh observations of an M 2.4 two-ribbon flare that began on 1999 July 25 at about 13:08 UT. We obser ve impulsive footpoint brightenings that are followed by the formation of h igh-temperature plasma (T-e greater than or similar to 10 MK) in the corona . After an interval of about 1300 s, cooler loops (T-e < 2 MK) form below t he hot plasma. Thus, the evolution of the event supports the qualitative as pects of the standard reconnection model of solar flares. The TRACE and Yoh koh data show that the bulk of the flare emission is at or below 10 MK. The TRACE data are also consistent with the Yohkoh observations of hotter plas ma (T-e similar to 15-20 MK) existing at the top of the arcade. The cooling time inferred from these observations is consistent with a hybrid cooling time based on thermal conduction and radiative cooling.