Title : Reliable Size Measurement of Massive Galaxies at z~0.5-3.0 in the 
GOODS-N region with HST/WFC3 Data

Author : Takahiro Morishita, Takashi Ichikawa

Abstract : 
We analyze the recent released HST/WFC3 IR images in the GOODS-N region and 
derive the size-stellar mass relations for massive (>10^10Msun) galaxies at z 
~0.5-3.0.
We use GALFIT to obtain the morphological parameters of the massive galaxies 
after examining the reliability of the fitting method with artificial galaxies. 
With a careful study of the bias and error in the effective radius, re, we find 
the median sizes for the QGs increase from z~3.0 to ~0.5 by a factor of ~2, 
while milder size evolution for the star-forming galaxies (SFGs), which is 
consistent with previous studies.
In addition, we find the evolution of Sersic index, n, of the QGs to be n∝
(1+z)^-α with α=0.70±0.37, while that of SFGs is unchanged (n~1) over the 
redshift range.
We discuss the evolution of re and $n$ in the perspective of minor merging.