Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exploring the evolutionary paths of the most massive galaxies since z~2   We use Spitzer MIPS data from the FIDEL Legacy Project in the Extended Groth
Strip to analyze the stellar mass assembly of massive (M>10^11 M_sun) galaxies
at z<2 as a function of structural parameters. We find 24 micron emission for
more than 85% of the massive galaxies morphologically classified as disks, and
for more than 57% of the massive systems morphologically classified as
spheroids at any redshift, with about 8% of sources harboring a bright X-ray
and/or infrared emitting AGN. More noticeably, 60% of all compact massive
galaxies at z=1-2 are detected at 24 micron, even when rest-frame optical
colors reveal that they are dead and evolving passively. For spheroid-like
galaxies at a given stellar mass, the sizes of MIPS non-detections are smaller
by a factor of 1.2 in comparison with IR-bright sources. We find that disk-like
massive galaxies present specific SFRs ranging from 0.04 to 0.2 Gyr^-1 at z<1
(SFRs ranging from 1 to 10 M_sun/yr), typically a factor of 3-6 higher than
massive spheroid-like objects in the same redshift range. At z>1, and more
pronouncedly at z>1.3, the median specific SFRs of the disks and spheroids
detected by MIPS are very similar, ranging from 0.1 to 1 Gyr^-1 (SFR=10-200
M_sun/yr). We estimate that massive spheroid-like galaxies may have doubled (at
the most) their stellar mass from star-forming events at z<2: less than 20%
mass increase at 1.7<z<2.0, up to 40% more at 1.1<z<1.7, and less than 20%
additional increase at z<1. Disk-like galaxies may have tripled (at the most)
their stellar mass at z<2 from star formation alone: up to 40% mass increase at
1.7<z<2.0, and less than 180% additional increase below z=1.7 occurred at a
steady rate.

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The categories of this paper are: cs
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: q-alg
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The categories of this paper are: hep-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: dg-ga
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The categories of this paper are: mtrl-th