TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2309 SUBJECT: SGR 1806-20, submm observations DATE: 03/07/19 05:22:38 GMT FROM: Sylvio Klose at TLS Tautenburg S. Klose (@SEST), B. Stecklum, & H. Linz, Thuringer Landessternwarte Tautenburg , J. Greiner, MPE Garching, report: We observed the field of SGR 1806-20 with the Swedish-ESO Submillimetre Telesco pe (SEST) at La Silla, Chile, on July 18/19, 0:35 - 2:10 UT. The observations were performed with the SIMBA Imaging Bolometer Array at a wavelength of 1.2mm and s tarted approximately 45 min after an outburst was recorded from SGR 1806 by HETE 2 and ended approximately 1.5 hrs before the next outburst was recorded (Hurley et al ., GCN 2308). A superposition of 4 maps (400 x 600 arcsec), 8 min mapping time eac h, does not reveal any source at the position of the SGR down to a flux density li mit of approximately 100 mJy.