Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The IDSA and the homogeneous sphere: Issues and possible improvements   In this paper, we are concerned with the study of the Isotropic Diffusion
Source Approximation (IDSA) (Baxter et al., Phys. Rev. E 73, 046118, 2006) of
radiative transfer. After having recalled well-known limits of the radiative
transfer equation, we present the IDSA and adapt it to the case of the
homogeneous sphere. We then show that for this example the IDSA suffers from
severe numerical difficulties. We argue that these difficulties originate in
the min-max switch coupling mechanism used in the IDSA. To overcome this
problem we reformulate the IDSA to avoid the problematic coupling. This allows
us to access the modeling error of the IDSA for the homogeneous sphere test
case. The IDSA is shown to overestimate the streaming component, hence we
propose a new version of the IDSA which is numerically shown to be more
accurate than the old one.
  Analytical results and numerical tests are provided to support the accuracy
of the new proposed approximation.

10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph