Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Theory of Vibronic Laser   Some aspects of lasing at vibronic transitions in impurity crystals are
theoretically studied. The threshold conditions for a vibronic laser are shown
to be dependent on the strength of interaction of optical centers with a local
vibration, which forms the vibronic spectrum, and the crystal lattice
temperature. The theory can be easily generalized to the spectrum containing a
structureless phonon sideband and well agrees with the experimental temperature
dependence of the output power of a Mg2SiO4:Cr4+ forsterite laser.

28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci