GRB 050509b: no optical variability in XRT error circle. Cenko, S. B. ; Soifer, B. T. ; Bian, C. ; Desai, V. ; Kulkarni, S. R. ; Schmidt, B. P. ; Dey, A. ; Jannuzi, B. T. Abstract Publication: GRB Coordinates Network Pub Date: 2005 Bibcode: 2005GCN..3409....1C