NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
MULTIWAVELENGTH ANALYSIS OF A SOLAR FLARE ON 2002 APRIL 15We carried out a multiwavelength analysis of the solar limb flare on 2002 April 15. The observations all indicate that the flare occurred in an active region with an asymmetric dipole magnetic configuration. The earlier conclusion that magnetic reconnection is occurring in a large-scale current sheet in this flare is M e r supported by these observations: (1) Several bloblike sources, seen in RHESSI 12-25 keV X-ray images later in the flare, appeared along a line above the flare loops. These indicate the continued presence of the current sheet and are likely to be magnetic islands in the stretched sheet produced by the tearing-mode instability. (2) A cusplike structure is seen in Nobeyama Radioheliogiaph (NoRH) 34 GHz microwave images around the time of the peak flare emission. We quantitatively demonstrate that the X-ray-emitting thermal plasma seen with RHESSI had a higher temperature than the microwave-emitting plasma seen with NoRH. Since the radio data preferentially see cooler thermal plasma, this result is consistent with the picture in which energy release occurs at progressively greater heights and the hard X-rays see hot new loops while the radio sees older cooling loops. The kinetic energy of the coronal mass ejection (CME) associated with this flare was found to be about 1 order of magnitude less than both the thermal energy in the hot plasma and the nonthermal energy carried by the accelerated electrons in the flare, as deduced from the RHESSI observations. This contrasts with the higher CME kinetic energies typically deduced for large flares.
Document ID
20060012347
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Sui, Linhui
(Catholic Univ. of America Washington, DC, United States)
Holman, Gordon D.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
White, Stephen M.
(Maryland Univ. College Park, MD, United States)
Zhang, Jie
(George Mason Univ. Fairfax, VA, United States)
Date Acquired
August 23, 2013
Publication Date
January 1, 2005
Publication Information
Publication: The Astrophysical Journal
Publisher: American Astronomical Society
Volume: 633
Subject Category
Solar Physics
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available