TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4314 SUBJECT: IPN observations of SGR1806-20 DATE: 05/12/09 22:02:55 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley and T. Cline, on behalf of the Ulysses, Mars Odyssey, and Konus GRB teams, I. Mitrofanov, A. Kozyrev, M. Litvak, A. Sanin, V. Tret'yakov and A. Parshukov, on behalf of the HEND-Odyssey GRB team, W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on behalf of the GRS-Odyssey GRB team, S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, and D. Frederiks, on behalf of the Konus-Wind team, S. Barthelmy, J. Cummings, N. Gehrels, and H. Krimm, on behalf of the Swift team, A. von Kienlin, G. Lichti, A. Rau, D. Gotz, and S. Mereghetti, on behalf of the INTEGRAL GRB team, and D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, W. Hajdas, A. Zehnder, S. Boggs, and M. Bandstra, on behalf of the RHESSI GRB team, report: Various IPN spacecraft have observed the possible activity of SGR1806-20 (Golenetski et al. GCN Circ. 4310, 4312). The following table summarizes the results. DATE TIME REFERENCE ANNULUS CENTER ANNULUS RADIUS DISTANCE FROM SPACECRAFT SGR1801? GCN # RA DEC SGR1806-20 051201 35965 4310 216.911 -15.332 52.530+/-0.345 0.069 K,O,R No 051203 32626 4310 216.686 -15.337 52.647+/-0.275 0.161 K,O No 051203 42204 4312 273.814 -20.444 7.139+/-7.139 5.692 K,R,S,I Yes NOTES: The annulus center RA and Dec are J2000. The uncertainty in the radius is 3 sigma. The distance from SGR1806-20 is the distance between the center line of the annulus and the source, in degrees. The spacecraft are Konus (K), Odyssey (O), RHESSI (R), Swift (S), and INTEGRAL (I); Ulysses was off. SGR1801? indicates whether the IPN annulus is consistent with the position of SGR1801-23 (Cline et al., Ap.J. 531, 407, 2000). For the first event on 051203, SGR1806 and SGR1801 were Earth-occulted for RHESSI. The triangulation annulus (actually a circle) for the second event on 051203 is also consistent with the position of the bursting pulsar, GROJ1744-28. These localizations support the conclusion that the source of the first two events, and therefore probably the third also, is indeed SGR1806-20.