Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Grain Formation in Post-Shocked Wind Collisions of Massive Binary
  Systems   Massive binary star systems are not uncommon, and neither the supersonic
collision of their winds. In the present work we study these shocks and the
further consequences on wind structure. The post-shock gas is a warm and
high-density environment, which allows dust to form and grow. We show that this
growth is fast, of just a few hours. An application for etaCarinae shows that,
probably, the decline of X-rays fluxes observed in its light curve is the
consequence of its high absorption in periodic dust formation events, on the
periastron passage.

7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th