Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scalar wave scattering by two-layer radial inhomogeneities   It is known that the Jost-function formulation of quantum scattering theory
can be applied to classical problems concerned with the scattering of a plane
scalar wave by a medium with a spherically symmetric inhomogeneity of finite
extent. This technique is applied to solve the radial differential equation for
the scattering from a constant spherical inhomogeneity and a piecewise constant
by two-layer spherical inhomogeneity. This could represent a spherical
scatterer with a piecewise increasing or decreasing refractive index, for
example. When the problem cannot be solved analytically in closed form, the
Jost integral formula can be used to convert it into an integral equation with
the corresponding boundary conditions.

15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th