Changes in X-ray brightness of a solar active region.
Abstract
The soft X-ray flux in the waveband from 0.3 to 0.9 nm has been monitored during most of the solar-disk passage of McMath region 12094. These data show how the emission changed during quiet periods as well as during flaring. Throughout the first four days of observations, the mean flux showed a gradual decay, even though the magnetic region was still growing. At the end of this phase, the region remained extremely inactive for almost half a day, and then brightened by more than an order of magnitude within an hour. This enhancement lasted nearly one day, and marked the onset of the break-up of the region. It is shown how this sequence of events might reflect changes in the subphotospheric convection pattern which is considered to develop in magnetic regions.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1976
- DOI:
- 10.1093/mnras/175.1.33
- Bibcode:
- 1976MNRAS.175...33G
- Keywords:
-
- Emission Spectra;
- Solar Activity;
- Solar X-Rays;
- Spectroheliographs;
- Oso-5;
- Satellite-Borne Instruments;
- Solar Flares;
- Sunspots;
- Time Response;
- Solar Physics