Spectrographic Observations of the Flare of July 20, 1961
Abstract
Spectroscopic observations of the late stages of a limb flare which occurred on July 20,1961, are presented. Because these observations were made with an achromatic coronagraph, accurate line intensity ratios are possible. The He I and He ii line ratios indicate a recombination-cascade spectrum. Measurements of cbntinuum densities give values around 1010 in the post-flare loop region and 1011 or more in the flare. Ca xv line widths correspond to 4.3 X 100 K. A magnetic loop structure which guides successive surges is studied.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1967
- DOI:
- 10.1086/149172
- Bibcode:
- 1967ApJ...148..501Z