Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectroscopic Study of the Envelope of the Hybrid Nova V458 Vul and
  Surrounding Nebula   Spectroscopic observations of the hybrid V458 Vul obtained between days 9 and
778 after the brightness maximum are analyzed. Short-period, daily profile
variations of forbidden [FeVII] iron lines were detected in the nebular phase,
as well as a long-period (about 60-day) cyclic variation that was correlated
with the photometric and X-ray cycles. The abundances of helium, neon, and iron
in the nova's envelope have been estimated. The helium, neon, and iron
abundances exceed the solar values by factors of 4.4, 4.8, and 3.7. The
envelope mass is 1.4$\times$ 10$^{-5}$M$_{\odot}$. The electron temperatures
and number densities have been calculated for the Northwestern and Southeastern
knots of the planetary nebula. The temperature derived for the Northwestern
knot is Te = 10 000 K and the electron number density, n$_{e}$ = 600 cm $^{-3}$
for the Southeastern knot, Te = 13 000 K and n$_{e}$ = 750 cm$^{-3}$.

15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph