Deep follow-up observations of XRF011019 by subaru telescope

摘要

We carried out the deep follow-up observations of XRF011019 field using Suprime-Cam equipped with Subaru telescope at Mauna Kea. XRF011019 was localized by the Wide Field X-ray Monitor on board HETE-2 (Ricker et al. GCN1109). The events is so-called X-ray Flash (XRF). We had four epoch observations; twice on 2001 October 20, once on 2001 November 17, and finally in on 2002 January 12. The first two observations (on October 20) recorded two sources, which were absent in the third observation performed about a month later. One of the candidates is located near the X-ray position centroid, while the other is located outside the 95.5% error region of similar to30' radius. The former object could be the optical counterpart to the X-ray flash.