dust obscuration. We also found a surface-density enhancement of EROs around the SCUBA source in the MS $0440.5+0204$ field.'
author:
- |
    Tadafumi <span style="font-variant:small-caps;">Takata</span>, Nobunari <span style="font-variant:small-caps;">Kashikawa</span>, Kouichiro <span style="font-variant:small-caps;">Nakanishi</span>,\
    Kentaro <span style="font-variant:small-caps;">Aoki</span>, Ryo <span style="font-variant:small-caps;">Asai</span>, Noboru <span style="font-variant:small-caps;">Ebizuka</span>, Motoko <span style="font-variant:small-caps;">Inata</span>, Masanori <span style="font-variant:small-caps;">Iye</span>,\
    Koji S. <span style="font-variant:small-caps;">Kawabata</span>, George <span style="font-variant:small-caps;">Kosugi</span>, Youichi <span style="font-variant:small-caps;">Ohyama</span>, Kiichi <span style="font-variant:small-caps;">Okita</span>,\
    Toshiyuki <span style="font-variant:small-caps;">Sasaki</span>, Yoshihiko <span style="font-variant:small-caps;">Saito</span>, Kazuhiro <span style="font-variant:small-caps;">Sekiguchi</span>, Yasuhiro <span style="font-variant:small-caps;">Shimizu</span>,\
    Hiroko <span style="font-variant:small-caps;">Taguchi</span>, and Michitoshi <span style="font-variant:small-caps;">Yoshida</span>
title: Dusty ERO Search behind Two Massive Clusters
---

Introduction
============

Following the commissioning of SCUBA on JCMT(Holland et al. 1999), sub-mm surveys of distant universe have rapidly increased the number of sub-mm selected galaxies (Hughes et al. 1998; Eales et al. 1999; Barger et al. 1998; Smail et al. 1997, 2002a; Chapman et al. 2002a; Fox et al. 2002; Scott et al. 2002). The advantages of selecting high-redshift objects based on a sub-mm wavelength are not only their negative [*[k]{}*]{}-correction up to $z \sim 10$ (Blain et al. 2002) but also their high sensitivity to very dusty objects, which are believed to be undergoing vigorous star formation at high redshift \[their median redshift is revealed to be $\sim$2.4(Smail et al. 2002a; 