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GCN Circular 2571

GRB 040403, deep optical observations
2004-04-22T07:37:37Z (20 years ago)
Alberto Castro-Tirado at Astro. de Andalucia <>
GRB 040403, deep optical observations

A. de Ugarte, A. Sota, J. Gorosabel and A. J. Castro-Tirado
(Instituto de Astrof�sica de Andaluc�a, IAA-CSIC, Granada),
and J. M. Castro Cer�n (STScI, Baltimore)


"We observed the field of the X-ray rich GRB 040403 detected
by INTEGRAL (GCN Circ. 2560, Gotz et al.) starting on 3 Apr
2004 (20:00 UT)  with the 1.5 m telescope at the Observatorio
de Sierra Nevada in Granada. Imagery was obtained in the R-
band (6 x 600 s). Comparison images were adquired on 4 and 20
Apr 2004 (9 x 600 s). No optical variable source is detected
within the 3' radius error box provided by IBIS/IGRIS down
to a limiting magnitude of 22.2 (3 sigma) 15 hr after the
event. This might be indicative of a dark GRB."

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