Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Galaxy distribution and evolution around a sample of 2dF groups   We study galaxy evolution and spatial patterns in the surroundings of a
sample of 2dF groups. Our aim is to find evidence of galaxy evolution and
clustering out to 10 times the virial radius of the groups and so redefine
their properties according to the spatial patterns in the fields and relate
them to galaxy evolution. Group members and interlopers were redefined after
the identification of gaps in the redshift distribution. We then used
exploratory spatial statistics based on the second moment of the Ripley
function to probe the anisotropy in the galaxy distribution around the groups.
We found an important anticorrelation between anisotropy and the fraction of
early-type galaxies in these fields. Our results illustrate how the dynamical
state of galaxy groups can be ascertained by the systematic study of their
neighborhoods.This is an important achievement, since the correct estimate of
the extent to which galaxies are affected by the group environment and follow
large-scale filamentary structure is relevant to understanding the process of
galaxy clustering and evolution in the Universe.

21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn