Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morphological Dependence of Star Formation Properties for the Galaxies
  in the Merging Galaxy Cluster A2255   The merging cluster of galaxies A2255 is covered by the Sloan Digital Sky
Survey (SDSS) survey. In this paper we perform a morphological classification
on the basis of the SDSS imaging and spectral data, and investigate the
morphological dependence of the star formation rates (SFRs) for these member
galaxies. As we expect, a tight correlation between the normalized SFR by
stellar mass (SFR/M$_*$) and the H$\alpha$ equivalent width is found for the
late-type galaxies in A2255. The correlation of SFR/M$_*$ with the continuum
break strength at 4000 \AA is also confirmed. The SFR/M$_*$ - M$_*$ correlation
is found for both the early- and late-type galaxies, indicating that the star
formation activity tends to be suppressed when the assembled stellar mass
M$_*$) increases, and this correlation is tighter and steeper for the late-type
cluster galaxies. Compared with the mass range of field spiral galaxies, only
two massive late-type galaxies with M$_*>10^{11}$ M$_{\odot}$ are survived in
A2255, suggesting that the gas disks of massive spiral galaxies could have been
tidally stripped during cluster formation. Additionally, the SFR variation with
the projected radial distance are found to be heavily dependent upon galaxy
morphology: the early-type galaxies have a very weak inner decrease in
SFR/M$_*$, while the inner late-type galaxies tend to have higher SFR/M$_*$
values than the outer late-types. This may suggest that the galaxy-scale
turbulence stimulated by the merging of subclusters might have played different
roles on early- and late-type galaxies, which leads to a suppression of the
star formation activity for E/S0 galaxies and a SFR enhancement for spiral and
irregular galaxies.

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The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys