Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Making Galaxies in a Cosmological Context: The Need for Early Stellar
  Feedback   We introduce the Making Galaxies in a Cosmological Context (MaGICC) program
of smoothed particle hydrodynamics (SPH) simulations. We describe a parameter
study of galaxy formation simulations of an L* galaxy that uses early stellar
feedback combined with supernova feedback to match the stellar mass--halo mass
relationship. While supernova feedback alone can reduce star formation enough
to match the stellar mass--halo mass relationship, the galaxy forms too many
stars before z=2 to match the evolution seen using abundance matching. Our
early stellar feedback is purely thermal and thus operates like a UV ionization
source as well as providing some additional pressure from the radiation of
massive, young stars. The early feedback heats gas to >10^6 K before cooling to
10^4 K. The pressure from this hot gas creates a more extended disk and
prevents more star formation prior to z=1 than supernovae feedback alone. The
resulting disk galaxy has a flat rotation curve, an exponential surface
brightness profile, and matches a wide range of disk scaling relationships. The
disk forms from the inside-out with an increasing exponential scale length as
the galaxy evolves. Overall, early stellar feedback helps to simulate galaxies
that match observational results at low and high redshifts.

15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas