TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2609 SUBJECT: SGR 1806-20: no IR variability of the proposed counterparts DATE: 04/06/09 17:33:11 GMT FROM: Stefano Covino at Brera Astronomical Observatory G.L. Israel, R. Mignani, S. Covino, S. Campana, L. Stella, N. Rea, V. Testa, G. Marconi on behalf of a larger team report: We have imaged in J, H and Ks bands with VLT/NACO the field of SGR 1806-20 on March 9th, 10th, 16th and 17th 2004. Observations were activated after the X-ray burst that occurred on March 9th (Mereghetti et al., GCN 2541). We have detected several sources within the Chandra error circle reported in Eikenberry et al. 2001 (ApJ 563, L133) including those reported in GCN 2607 (Kouveliotou et al.). The monitoring of these objects did not show any variability more significant than 2sigma in the Ks band on time scales from hours up to days. The limiting Ks magnitude was about 21.5. Both the lack of IR variability correlated to the X-ray burst activity and the relatively high IR flux for the proposed counterparts (GCN 2607) suggest that these objects are unlikely the IR counterpart to SGR 1806-20. This message can be cited.