Astronomy and Astrophysics – Astronomy
Scientific paper
Apr 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997apj...479l.149s&link_type=abstract
Astrophysical Journal Letters v.479, p.L149
Astronomy and Astrophysics
Astronomy
12
Sun: Corona, Sun: Flares, Sun: X-Rays, Gamma Rays
Scientific paper
We present the first high-resolution soft X-ray spectral observations of the corona above an active region, using the Bragg crystal spectrometer (BCS) on board the Yohkoh satellite. We observed NOAA AR 7978 as it rotated beyond the solar limb so that the lower portions of the region were occulted. Long integrations from times after the region had totally disappeared some days later show a substantial, variable background in S XV. Since the background spectrum is featureless, spectral lines obtained from the time of occultation must originate from the upper corona of the active region. Our results support previous findings that the active region corona consists of two components: a cooler, steady component with Te ~ 3 MK and a hotter, transient component in excess of 5 MK. This hotter component is due to microflares; outside the time of microflares there is relatively little or no active region upper coronal plasma with Te >~ 3.5 MK. There is evidence for a decrease in Te with height for the cool component.
Hudson Hugh S.
Sterling Alphonse C.
Watanabe Tetsuya
No associations
LandOfFree
Electron Temperatures of the Corona Above a Solar Active Region Determined from S XV Spectra 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 Electron Temperatures of the Corona Above a Solar Active Region Determined from S XV Spectra, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electron Temperatures of the Corona Above a Solar Active Region Determined from S XV Spectra will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1316959