NDELS场中z~2星系的形态结构研究

Using the multi-band photometry data of all five CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) fields and the high-resolution HST WFC3 (Hubble Space Telescope Wide Field Camera 3) near-infrared imaging (F160W), we present a quantitative study of morphology and structure ofBzK-selected (two-color ${ m B-z}$ vs. ${m z-K}$ diagram) Galaxies. The sample of 1857 BzKs including 1586 star-forming galaxies (sBzKs) and 271 passively evolving galaxies (pBzKs). The mean redshifts of sBzKs and pBzKs are $1.80pm0.49$ and $1.73pm0.38$, respectively. For the rest-frame optical morphologies of sBzKs (pBzKs), the fractionsof ellipticals, disks, and irregular galaxies correspond to 15% (44%), 18%(37%), and 67%(19%), respectively.Moreover, the median effective radii of sBzKs and pBzKs, corresponding to $2.52pm1.37$ kpc and $1.90pm1.02$ kpc, respectively. The findings show that the sizes of pBzKs (sBzKs) are smaller than that of present-day early-type (late-type) galaxies with analogous stellar mass at rest-frame optical wavelength, indicatingthe evolution of high-redshift massive galaxy size with redshift.