Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The effect of ultra-violet photon pumping of H$_2$ in dust-deficient
  protoplanetary disks   We perform radiation hydrodynamics simulations to study the structure and
evolution of a protoplanetary disk. Ultraviolet and X-ray radiation from the
host star heats the disk surface, where H$_2$ pumping also operates
efficiently. We run a set of simulations with varying the amount of dust
grains, or the dust-to-gas mass ratio, which determines the relative importance
between photoelectric heating and H$_2$ pumping. We show that H$_2$ pumping and
X-ray heating contributes stronger to the mass-loss of the disk if the
dust-to-gas mass ratio is $\mathcal{D}\leq10^{-3}$. In such dust-deficient
disks, H$_2$ pumping enhances photoevaporation from the inner disk region and
shapes the disk mass-loss profile. The long-term disk dispersal process may be
affected by the ultra-violet H$_2$ pumping effect.

27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio