Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Note on an integral expression for the average lifetime of the bound
  state in 2D   Recently, an exact Green's function of the diffusion equation for a pair of
spherical interacting particles in two dimensions subject to a backreaction
boundary condition was used to derive an exact expression for the average
lifetime of the bound state. Here, we show that the corresponding divergent
integral may be considered as the formal limit of a Stieltjes transform. Upon
analytically calculating the Stieltjes transform one can obtain an exact
expression for the finite part of the divergent integral and hence for the
average lifetime.

33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th