Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Two-Fluid Method for Ambipolar Diffusion   We present a semi-implicit method for isothermal two-fluid ion-neutral
ambipolar drift that is second-order accurate in space and time. The method has
been implemented in the RIEMANN code for astrophysical fluid dynamics. We
present four test problems that show the method works and correctly tracks the
propagation of MHD waves and the structure of two-fluid C-shocks. The accurate
propagation of MHD waves in the two-fluid approximation is shown to be a
stringent test of the algorithm. We demonstrate that highly accurate methods
are required in order to properly capture the MHD wave behaviour in the
presence of ion-neutral friction.

7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci