Astronomy and Astrophysics – Astronomy
Scientific paper
Feb 1996
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996apj...458l..49s&link_type=abstract
Astrophysical Journal Letters v.458, p.L49
Astronomy and Astrophysics
Astronomy
14
Sun: Flares
Scientific paper
We present the first high spatial resolution images of a solar flare at millimeter wavelengths. On 1994 August 17, a GOES soft X-ray class M1 flare was observed by the Berkeley-Illinois-Maryland Array at 86 GHz by the Nobeyama 17 GHz array and by the Yohkoh spacecraft. The flare displayed both a prominent impulsive phase in microwaves and a gradual phase that lasted over 30 minutes. The millimeter data were taken only during the gradual phase. The millimeter images show a source with a size of ~8", a peak brightness temperature of ~106 K, and maximum optical depth of 0.09. At both X-ray and radio wavelengths, the emitting region appeared to be compact (<~20"). In soft X-ray, the images are resolved into two sources: one located at a footpoint and the other at the top of the flaring loop. The millimeter emission is consistent with the predicted free-free flux from an isothermal temperature (~14 MK) loop-top source, a multitemperature footpoint source with a hot (~22 MK), and a cold (~12 MK) component. Most (80%) of the millimeter flux density originates from the top of the magnetic loop, and the footpoint contribution is only 20%.
de Pater Imke
Hudson Hugh S.
Kundu Mukul R.
Lin Robert P.
Shibasaki Kazuo
No associations
LandOfFree
First Images of a Solar Flare at Millimeter Wavelengths does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with First Images of a Solar Flare at Millimeter Wavelengths, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and First Images of a Solar Flare at Millimeter Wavelengths will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1153897