@misc{oai:ir.soken.ac.jp:00001415, author = {古澤, 順子 and フルサワ, ジュンコ and FURUSAWA, Junko}, month = {2016-02-17}, note = {We investigate mass-dependent galaxy evolution based on a large sample of, about 50,000, K-band selected galaxies in a multi-wavelength catalog of the Subaru/XMM- Newton Deep Survey (SXDS) and the UKIRT Infrared Deep Sky Survey (UKIDSS), Ultra Deep Survey (UDS). After we discriminate galaxies from stars and various false objects, we employ the optical to near-infrared photometry to determine photometric redshifts of these galaxies. Then, we estimate the stellar mass of our sample galaxies using the same standard fitting procedure as used for estimate the photometric redshift (photo-z). Since we employ exactly the same SED models both in the photo-z determination and mass estimation, stellar masses of galaxies thus obtained are internally consistent with the photo-z and other physical parameters of the best-fit SEDs, including age, metallicity, extinction due to the internal dust, etc. We compute the stellar mass function and the stellar mass density (SMD) up to redshift z=4. By combining a large number of stellar masses and spatial distributions of galaxies in one contiguous wide and deep field, we examine properties of the mass-dependent clustering of galaxies. Compared to previous studies, we are able to estimate stellar mass functions more accurately over the wider redshift range and, also, we can investigate properties of the K-selected galaxies to much lower-mass galaxies (M*~10^10.5MΘ) at high-z (up to 3≦z<4).
　The clustering properties derived from our data are relatively free from the field-to-field variation with the aid of the wide survey area. This enables us to investigate not only the evolution of stellar mass of galaxies but also the clustering evolution of galaxies as a function of the stellar mass up to the redshift z = 4.
　In order to discuss the clustering properties of the galaxies quantitatively, we derive the two-point angular correlation functions (ACFs) w(θ), using the technique proposed by Landy & Szalay (1993). The ACF shows the clustering properties of galaxies projected on the sky. From a given angular clustering measurement, the correlation length r0 of galaxies for each mass range can be estimated by the Limber equation (Limber 1953) using the redshift distribution of galaxies and a choice of cosmology (e.g., Peebles 1980). Since the spatial correlation function (SCF) obtained from a combination of w(θ) and the redshift distribution of sample galaxies should reflect the intrinsic clustering in the space, r0 shows the spatial clustering strength of sample galaxies. An observed trend we found is in good agreement with the local scaling behavior of the clustering with stellar mass of galaxies. More massive galaxies have stronger clustering at z<4. The most massive dark haloes (MDHs) are likely to host the most massive galaxies. On the other hand, the intermediate-mass galaxies (10^10.5MΘ10.9 MΘ) may also be hosted in somewhat lower-mass DHs at the various different redshifts. We find that the turning redshift point of changing the dark matter haloes hosting the intermediate-mass galaxies is at z~2. We also find several high mass density regions of massive galaxies at 1.4≦z<2.5 in our sample. These concentrations of massive galaxies are considered to be candidates of the present-day clusters of galaxies. We also investigate the clustering properties of galaxy populations including star-forming BzK (sBzK) and passively-evolving BzK galaxies (pBzK) which are classified by their colors. We find that a 77% of our massive galaxies at 1.4≦ z<2.5 are the massive sBzK galaxies, and the high mass-density regions at 1.4≦z<2.5 are composed primarily of the massive sBzK galaxies (M*>10^11.3 MΘ ). Thus, the massive galaxies at this epoch are dominated by the massive sBzK galaxies. These high mass-density regions may be the proto-clusters which evolve into the present-day massive clusters of galaxies. We also find that the average stellar mass of the pBzK galaxies at 1.4≦z<2.5 is ~10^10.8 MΘ. Although this average mass corresponds to that of the intermediate-mass galaxies, the clustering strength of the whole pBzK population is as high as that of the massive galaxies (M*≧10¹¹ MΘ). This result may suggest that the clustering structure of pBzK galaxies formed earlier than that of the sBzK galaxies at 1.4≦z<2.5, and may imprint the large-scale structures of massive galaxies at the earlier epoch., 総研大甲第1223号}, title = {The Clustering History of K-selected Galaxies at z<4 in the SXDS/UDS Field}, year = {} }