Return to Home Page
TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2123 SUBJECT: GRB 030329, light curve flattens DATE: 03/04/09 17:53:47 GMT FROM: Sylvio Klose at TLS Tautenburg <klose@tls-tautenburg.de> A. Henden (USRA/USNO, Flagstaff), B. Canzian (USNO), A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg), on behalf of the FUN and another collaboration report: Flagstaff BVRI data reveal that the light curve of the optical transient (OT) following GRB 030329 has now begun to flatten in all bands and might be entering the supernova phase. The signal which is now seen in the light curve shape looks different from all previous episodes of re-brightening. The photometric data alone do not yet allow us to state with certainty what the best fitting parameters of the underlying supernova component are (see Zeh et al., GCN 2081). The color evolution of the OT until day 8 after the burst, which was reported in GCN 2115 (Zeh et al.), seemed to prefer a delay dt between the onset of the supernova and the onset of the GRB by several days. The inclusion of the Flagstaff data obtained during the last two nights has changed this picture, however. Obviously on day 8 the OT underwent another episode of re-brightening and color change that made it difficult to fit the observed colors. After exclusion of this effect, a dt close to 0 days is preferred in the color evolution, as well as in the shape of the R and V-band light curves (-3 < dt <=0). This is in good agreement with the (stronger) finding based on spectroscopic data (Matheson et al., GCN 2120). Figures will be posted at Jochen Greiners internet GRB page.
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp
