Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Where are the First Stars now?   We use high-resolution simulations to show that the current standard paradigm
for the growth of structure in the Universe predicts the formation of a galaxy
like our own to differ substantially from the classic ELS and Searle/Zinn
pictures. On scales larger than the Local Group, the earliest star formation
was extremely inhomogeneous, suggesting that the high redshift intergalactic
medium should have large-scale abundance variations. The very oldest stars
should be found today in the central regions of rich galaxy clusters. In the
Milky Way's bulge and stellar halo little correlation is expected between age
and metallicity. Some of the lowest metallicity stars may be relatively young.
Many of the oldest stars may have high metallicity. Spheroid stars were formed
before and during halo assembly, the oldest now lying preferentially at small
radii, while low metallicity stars lie preferentially at large radii. The bulk
of the Milky Way's stellar spheroid came from a small number of progenitors. It
should show little spatial structure in the inner 5 to 15 kpc, but consist at
each point of a superposition of hundreds of `cold' streams. Such streams have
been detected in the Solar neighborhood.

10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph