Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relaxation in quantum systems. Manifestation of the state-selective
  reactive decay   The effect of state-selective reactive decay on the relaxation kinetics of
quantum multistate systems is studied in detail in the Bloch-Redfield approach
(BRA). The results are applied to the analysis of this effect in radical pair
recombination kinetics. The BRA is shown to be able to describe quantitatively
most important specific features of the recombination kinetics including those
predicted by phenomenological treatment and by recently proposed approaches
based on quantum measurement theories.

34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex