Takashi Ichikawa, Masaru Kajisawa, Mohammad Akhlaghi
We present scaling relations between stellar-mass (Mstar) and the size of
galaxies at 0.3 < z < 3 for half- (R_50) and 90 percent-light (R_90) radii,
using a deep K-band selected catalogue taken with the Subaru Telescope and
MOIRCS in the GOODS-North region. The logarithmic slope R \propto
Mstar^{0.1-0.2} is independent of redshift in a wide mass range of Mstar ~
10^8-10^11 Msun, irrespective of galaxy populations (star-forming, quiescent).
The offset change is < 50 percent. Provided that optical light in the rest
frame traces the stellar mass of galaxies, the universal relation demonstrates
that the stellar mass was built up in galaxies over their cosmic histories in a
similar manner on average irrelevant to galaxy mass. The small offset in each
stellar mass bin from the universal relation shows weak size evolution at a
given mass. There is a moderate increase of 30-50 percent for R_50 and R_90 for
less massive galaxies (Mstar < 10^10 Msun) from z~3 to z~1, while the sizes
remains unchanged or slightly decrease towards z~0.3. For massive galaxies
(Mstar > 10^11 Msun), the evolution is ~70-80 % increase in R_90 from z~3 to
z~0.3, though that in R_50 is weaker. The evolution of compactness factor,
R_50/R_90, which becomes smaller at lower redshift, is suggestive of minor
merging effect in the outer envelope of massive galaxies.
View original:
http://arxiv.org/abs/1202.1138
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