TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2553 SUBJECT: GRB 040323, a dark GRB ? DATE: 04/03/23 22:25:10 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia GRB 040323, a dark GRB ? ---------------------------------------- A. J. Castro-Tirado, J. Gorosabel and A. de Ugarte (Instituto de Astrofísica de Andalucía, IAA-CSIC, Granada), P. Tristram (MJO, Canterbury Univ.), Ph. Yock (Auckland Univ.), M. Jelínek (Astronomical Observatory, Ondrejov), M.D. Pérez- Ramírez (Univ. de Jaén) and J. M. Castro Cerón (STScI, Baltimore) communicate: "We have observed the field of the GRB 040323 detected by INTEGRAL (GCN Circ. 2551, Mereghetti et al.) on 23 Mar 2004 (15:24 UT) with the 0.6-m telescope at Canterbury's Univ. Mt. John Observatory. Imagery was obtained in the I- and B-band (300-s exposure time each). No optical variable source is detected within the 2' radius error box provided by IBIS/IGRIS when comparing to the DSS-2. Even if there is considerable absorption towards this location (Av = 1.1), the fact that no afterglow is detected 2.33 hr after the event in the MJO images down to the DSS-2-Infrared limiting magnitude might be indicative of a dark GRB. We therefore encourage further deep, near-infrared imaging at larger telescopes." This message is quotable.