Physical Parameters of Solar X-Ray Jets
Abstract
We derived the physical parameters of X-ray jets and associated flares using the high-resolution data taken with the soft X-ray telescope aboard Yohkoh. We analyzed 16 X-ray jets and found the following properties of the jets and the footpoint flares: (1) the temperatures and density of the jets, respectively, are 3-8 MK (average: 5.6 MK) and 0.7-4.0×109 cm-3 (average: 1.7×109 cm-3), (2) the temperatures of the jets are similar to those of the footpoint flares, (3) the thermal energies of the jets are 1027-1029 ergs, which is 1/4 to 1/7 of those of the footpoint flares, (4) the apparent velocity of the jets is usually slower than the sound speed, and (5) there is a correlation between the temperatures of the jets and the sizes (square root of area) of the footpoint flares. On the basis of these results, we find that the temperatures of a jet and a footpoint flare are determined by the balance between heating flux and conductive flux and that the mass of a jet is comparable to the theoretical value based on the balance between conductive flux and enthalpy flux carried by the evaporation flow. These results suggest that X-ray jets are evaporation flows produced by the reconnection heating.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 2000
- DOI:
- 10.1086/317024
- Bibcode:
- 2000ApJ...542.1100S
- Keywords:
-
- Sun: Corona;
- Sun: Flares;
- Sun: X-Rays;
- Gamma Rays