TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2580 SUBJECT: GRB040422: optical observations at CrAO DATE: 04/04/25 13:10:40 GMT FROM: Vasilij Rumjantsev at CrAO V.Rumyantsev (CrAO) and A.Pozanenko (IKI) report: We have observed the error box of GRB 040422 (INTEGRAL trigger 1758, GCN2572, Mereghetti et. al) with 2.6 m Shajn telescope (F/3.9) at Crimean Astrophysical Observatory. The observation start (UT) Apr. 22, 23:37 under poor sky conditions (seeing ~2.5 arcsec). Several R-images taken between (UT) Apr. 22, 23:37 - Apr. 23, 01:39 with exposition 120 s of each frame covered 60% of the GRB error box. Comparison with DSS2 reveals no new objects brighter than limits of DSS2. The limiting magnitude of co-added images is ~21R. Combined mosaic image of GRB error box can be found at http://grb.rssi.ru/GRB040422 This message may be cited