Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morphological and Luminosity Content of Poor Galaxy Groups   We find that the fraction of early-type galaxies in poor groups (containing
from 4 to 10 members) is a weakly increasing function of the number of the
group members and is about two times higher than in a sample of isolated
galaxies. We also find that the group velocity dispersion increases weakly with
the fraction of early-type galaxies. Early-type galaxies in poor groups are
brighter in the near-infrared with respect to isolated ones by 0.75 mags (in K)
and to a lesser degree (by 0.5 mags) also in the blue. We also find early-type
galaxies in groups to be redder than those in the field. These findings suggest
that the formation history for early-type galaxies in overdense regions is
different from that of in underdense regions, and that their formation in
groups is triggered by merging processes.

15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio