Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pulsar bow-shock nebulae. III. Inclusion of a neutral component, and
  H_{a lpha} luminosity   The interaction of the wind from a pulsar (or more generally from a star)
with t he amb ient medium gives rise to the formation of a bow-shock nebula. We
present a mode l of adiabatic bow-shock nebulae, including the presence of a
neutral component in the interstellar medium. As demonstrated in a previous
paper (Bucciantini & Bandiera 2001}, hereafter Paper I), the velocity and the
luminosity of the pulsar, as well a s the characteristics of the interstellar
medium (ISM), play an essential role in determinin g the properties of bow
shock nebulae. In particular, the Balmer emission is strongly affect ed by the
rates of hydrogen charge-exchange and collisional excitation. So far, only
one-com ponent models have been proposed, treating the neutrals as a small
perturbation. The distrib ution of neutral hydrogen in the nebula, derived by
our model, is then used to determine how the h_{alpha} luminosity varies along
the bow shock. We find that the luminosity trend is d ifferent for
charge-exchange and collisional excitation, and that processes like diffusion o
r ionization may reduce the emission in the head of the nebula.

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The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
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The categories of this paper are: eess
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph