CLUSTERING OF EXTREMELY RED OBJECTS IN THE SUBARU GTO 2DEG² FIELD

• Published in: Journal of the Korean Astronomical Society, 50(3) pp. 61 - 70
• Main Authors: 신지혜, 심현진, 황호성, 고종완, 이종철, Yousuke Utsumi, 황나래, 박병곤
• Format: Journal Article
• Language: English
• Published: 한국천문학회 01.07.2017
• Subjects: 천문학
• ISSN: 1225-4614; 2288-890X

We study the angular correlation function of bright ($K_s \leq 19.5$) Extremely Red Objects (EROs) selected in the Subaru GTO 2\,deg$^2$ field. By applying the color selection criteria of $R-K_s > 5.0, 5.5$, and $6.0$, we identify 9055, 4270, and 1777 EROs, respectively. The number density is consistent with similar studies on the optical $-$ NIR color selected red galaxies. The angular correlation functions are derived for EROs with different limiting magnitude and different $R-K_s$ color cut. When we assume that the angular correlation function $w(\theta)$ follows a form of a power-law (i.e., $w(\theta) = A\,\theta^{-\delta}$), the value of the amplitude $A$ was larger for brighter EROs compared to the fainter EROs. The result suggests that the brighter, thus more massive high-redshift galaxies, are clustered more strongly compared to the less massive galaxies. Assuming that EROs have redshift distribution centered at $\langle z \rangle \sim1.1$ with $\sigma_z=0.15$, the spatial correlation length $r_0$ of the EROs estimated from the observed angular correlation function ranges $\sim6$-$10\,h^{-1}$\,Mpc. A comparison with the clustering of dark matter halos in numerical simulation suggests that the EROs are located in most massive dark matter halos and could be progenitors of $L_*$ elliptical galaxies. KCI Citation Count: 4