Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 6343

GRB 070411: break in the optical light curve
2007-04-23T15:09:04Z (17 years ago)
Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center <>
D. Malesani (DARK/NBI), E. Rol (Univ. Leicester), L. A. Antonelli
(INAF/OAR), J.P.U. Fynbo (DARK/NBI), P.A. Curran (UVA), K. Wiersema (UVA),
A.J. Levan (Univ. Warwick), N.R. Tanvir (Univ. Leicester), V. Testa
(INAF/OAR), E. Palazzi (INAF/IASF Bo), A.O. Jaunsen (Univ. Oslo), C.C.
Thoene (DARK/NBI), J. Hjorth (DARK/NBI), P.M. Vreeswijk (ESO), report:

We have observed the optical afterglow of GRB 070411 (Moretti et al., GCN
6267), using the NOT, VLT, TNG, and WHT telescopes, in the R band.

Observations were carried out at several epochs, between 0.04 and 8 days
after the burst. Analysis of the light curve reveals a clear steepening at
~1 day after the GRB. The late-time slope alpha ~ 1.4 is well constrained
by our measurements (see also Ferrero et al., GCN 6319), and has a value
flatter than expected from post-jet break models (alpha >~ 2).

We encourage observations at X-ray wavelengths to test for the presence of
any break in the X-ray light curve.

We acknowledge support from the observers and the staff at the NOT, VLT,
TNG, and WHT telescopes.
Looking for U.S. government information and services? Visit