Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: X-ray and UV investigation into the magnetic connectivity of a solar
  flare   We investigate the X-ray and UV emission detected by RHESSI and TRACE in the
context of a solar flare on the 16th November 2002 with the goal of better
understanding the evolution of the flare. We analysed the characteristics of
the X-ray emission in the 12-25 and 25-50 keV energy range while we looked at
the UV emission at 1600 {\AA}. The flare appears to have two distinct phases of
emission separated by a 25-second time delay, with the first phase being
energetically more important. We found good temporal and spatial agreement
between the 25-50 keV X-rays and the most intense areas of the 1600 {\AA} UV
emission. We also observed an extended 100-arcsecond < 25 keV source that
appears coronal in nature and connects two separated UV ribbons later in the
flare. Using the observational properties in X-ray and UV wavelengths, we
propose two explanations for the flare evolution in relation to the spine/fan
magnetic field topology and the accelerated electrons. We find that a
combination of quasi separatrix layer reconnection and null-point reconnection
is required to account for the observed properties of the X-ray and UV
emission.

13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org