Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Numerical Simulations of Optically Thick Accretion onto a Black Hole -
  II. Rotating Flow   In this paper we report on recent upgrades to our general relativistic
radiation magnetohydrodynamics code, Cosmos++, including the development of a
new primitive inversion scheme and a hybrid implicit-explicit solver with a
more general closure relation for the radiation equations. The new hybrid
solver helps stabilize the treatment of the radiation source terms, while the
new closure allows for a much broader range of optical depths to be considered.
These changes allow us to expand by orders of magnitude the range of
temperatures, opacities, and mass accretion rates, and move a step closer
toward our goal of performing global simulations of
radiation-pressure-dominated black hole accretion disks. In this work we test
and validate the new method against an array of problems. We also demonstrate
its ability to handle super-Eddington, quasi-spherical accretion. Even with
just a single proof-of-principle simulation, we already see tantalizing hints
of the interesting phenomenology associated with the coupling of radiation and
gas in super-Eddington accretion flows.

9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs