Speaker
Dr
M. De Pasquale
(Mullard Space Science Laboratory - University College London)
Description
We present observations of GRB 130831A obtained by Swift, Chandra, and multiple ground-based observatories. This burst shows a remarkable drop in the X-ray light curve at about 10^5 s after the trigger, with a decay slope of \alpha_X \simeq 5. Such behaviour cannot be explained in the standard Forward Shock (FS) model, whereas it can be explained if the high energy emission is powered by a newly born magnetar. After the drop, the X-ray afterglow resumes a decay with a slope more typical of FS emission. The optical emission, on the other hand, shows no clear break across the X-ray drop, and its decay is similar to that of the late X-rays. We assume that the optical and late X-ray emission are both FS; we model our data to derive the kinetic energy of the ejecta and thus measure, for the first time, the efficiency of the magnetar as central engine of a Gamma-Ray Burst.
Primary author
Dr
M. De Pasquale
(Mullard Space Science Laboratory - University College London)
Co-authors
Dr
Adam Trotter
(University of North Carolina at Chapel Hill)
Dr
Alexander Kann
(Thüringer Landessternwarte Tautenburg Observatory)
Prof.
Alexei Pozanenko
(Space Research Institute, RAS, Russia)
Alina Volnova
(Sternberg Astronomical Institute, Moscow State University, Russia)
Dr
Antonino Cucchiara
(NASA/GSFC)
Prof.
Bing Zhang
(University of Nevada, Las Vegas)
Dr
Boris Sbarufatti
(Pennsylvania State University)
Dr
Eleonora Troja
(NASA/GSFC)
Prof.
Igor Molotov
(Keldysh Institute of Applied Mathematics)
Dr
Judith Racusin
(NASA/GSFC)
Prof.
Mathew Page
(Mullard Space Science Laboratory, University College London)
Mr
Nathan Frank
(University of North Carolina at Chapel Hill)
Prof.
Nathaniel Butler
(School of Earth & Space Exploration, Arizona State University)
Dr
Samantha Oates
(Mullard Space Science Laboratory)
Dr
Silvia Zane
(Mullard Space Science Laboratory)
Dr
Steve Schulze
(Pontificia Universidad Católica de Chile)
Prof.
Vasilij Rumyantsev
(Crimean Astrophysical Observatory)
Dr
Zach Cano
(University of Iceland)
