Asymmetric distribution of solar X-ray flares
Hari Om
1
1
Vats
and Niraj
2
Pandya
Physical Research Laboratory, Navrangpura, Ahmedabad, 380 009, INDIA. vats@prl.res.in
2 Tolani College of Arts and Science, Adipur, Gujarat, INDIA
Abstract
We pursued a statistical study of the X-ray flares using X-ray observation of GOES satellites. The investigations reveal that x-ray flares have preferential location on
the solar surface. Two examples are (1) out of 1077 total number X-ray flares in 1993; 55% occurred in northern hemisphere. The flare occurrence peaks at ~ 12.5
degree both in north and south. The peak in the northern hemisphere is considerably higher than that in south. (2) Out of 1962 total number of X-ray flares in
2004; 58% are in the southern hemisphere. Here too peak occurrence is ~12.5 degree both in north and south, however, southern peak is higher than that in
north. The distribution of peak and average flux during the flares in these years also have asymmetry, but of opposite sign.
20
Flare Occurrence (%)
Flare Occurrence (%)
30
2004
20
10
0
12
8
4
0
-20
-15
-10
-5
0
5
10
15
-25
20
-20
-15
-10
-5
0
5
10
15
20
25
1.2
1.2
1
1
2004
Peak flare intensity
x (3.39E+03)
x (2.09E+04)
1993
16
0.8
0.6
0.4
0.8
0.6
2004
0.4
0.2
0.2
0
0
Average flare intensity
-20
-15
-10
-5
0
5
10
Latitude in degrees
15
20
-20
-15
-10
-5
0
5
10
Latitude in degrees
15
20