Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing the evolution of galaxies using redshifted H-alpha emission   In this paper we review the present status and implications of H-alpha
surveys at various redshifts. With the advent of sensitive wide-format
near-infrared detectors on large telescopes, deep and extensive H-alpha surveys
are now feasible to redshift z~2.5. The cosmic star formation history can
therefore be traced out to this redshift using H-alpha alone, avoiding
complications arising from the comparison of different tracers at different
redshifts. The H-alpha surveys to date confirm the rapid increase in luminosity
density from z=0 out to z=1, and show that this increase flattens off at higher
redshifts, remaining approximately constant out to at least z~2.2. We also
discuss the prospects for determining the masses of high redshift galaxies
based on emission lines. A set of high-quality H-alpha rotation curves of
samples of disk galaxies at a number of different redshifts would allow a study
of the evolution of the Tully-Fisher relation and address fundamental issues in
disk galaxy formation. Such a program remains challenging even with present-day
large telescopes.

19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics