Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectroscopic and photometric study of the Mira stars SU Camelopardalis
  and RY Cephei   Miras are fascinating stars. A kappa-mechanism in their atmosphere drives
pulsations which produce changes in their photometric brightness, apparent
spectral type and effective temperature. These pulsations also drive the
formation of Balmer emission lines in the spectrum. This behaviour can be
observed and investigated with small telescopes. We report on a three-year
project combining spectroscopy and photometry to analyse the behaviour of Mira
stars SU Cam and RY Cep, and describe how their brightness, colour, spectral
type, effective temperature and Balmer emission vary over four pulsation
cycles.

17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th