Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Meaning and Consequences of Star Formation Criteria in Galaxy Models
  with Resolved Stellar Feedback   We consider the effects of different star formation criteria on galactic
scales, in high-resolution simulations with explicitly resolved GMCs and
stellar feedback. We compare: (1) a self-gravity criterion (based on the local
virial parameter and the assumption that self-gravitating gas collapses to high
density in a free-fall time), (2) a fixed density threshold, (3) a
molecular-gas law, (4) a temperature threshold, (5) a Jeans-instability
requirement, (6) a criteria that cooling times be shorter than dynamical times,
and (7) a convergent-flow criterion. We consider these both MW-like and
high-density (starburst) galaxies. With feedback present, all models produce
identical integrated star formation rates (SFRs), in agreement with the
Kennicutt relation. Without feedback all produce orders-of-magnitude excessive
SFRs. This is totally dependent on feedback and independent of the SF law.
However, the spatial and density distribution of SF depend strongly on the SF
criteria. Because cooling rates are generally fast and gas is turbulent,
criteria (4)-(7) are 'weak' and spread SF uniformly over the disk (above
densities n~0.01-0.1 cm^-3). A molecular criterion (3) localizes to higher
densities, but still a wide range; for Z Z_solar, it is similar to a density
threshold at n~1 cm^-3 (well below mean densities in the MW center or
starbursts). Fixed density thresholds (2) can always select the highest
densities, but must be adjusted for simulation resolution and galaxy
properties; the same threshold that works in a MW-like simulation will select
nearly all gas in a starburst. Binding criteria (1) tend to adaptively select
the largest over-densities, independent of galaxy model or resolution, and
automatically predict clustered SF. We argue that this SF model is most
physically-motivated and presents significant numerical advantages in
large-dynamic range simulations.

17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga