Bibcode
Cenko, S. B.; Butler, N. R.; Ofek, E. O.; Perley, D. A.; Morgan, A. N.; Frail, D. A.; Gorosabel, J.; Bloom, J. S.; Castro-Tirado, A. J.; Cepa, J.; Chandra, P.; de Ugarte Postigo, A.; Filippenko, A. V.; Klein, C. R.; Kulkarni, S. R.; Miller, A. A.; Nugent, P. E.; Starr, D. L.
Referencia bibliográfica
The Astronomical Journal, Volume 140, Issue 1, pp. 224-234 (2010).
Fecha de publicación:
7
2010
Número de citas
40
Número de citas referidas
35
Descripción
We present broadband (gamma-ray, X-ray, near-infrared, optical, and
radio) observations of the Swift gamma-ray burst (GRB) 090709A and its
afterglow in an effort to ascertain the origin of this high-energy
transient. Previous analyses suggested that GRB 090709A exhibited
quasi-periodic oscillations with a period of 8.06 s, a trait unknown in
long-duration GRBs but typical of flares from soft gamma-ray repeaters.
When properly accounting for the underlying shape of the power-density
spectrum of GRB 090709A, we find no conclusive (>3σ) evidence
for the reported periodicity. In conjunction with the location of the
transient (far from the Galactic plane and absent any nearby host galaxy
in the local universe) and the evidence for extinction in excess of the
Galactic value, we consider a magnetar origin relatively unlikely. A
long-duration GRB, however, can account for the majority of the observed
properties of this source. GRB 090709A is distinguished from other
long-duration GRBs primarily by the large amount of obscuration from its
host galaxy (A K,obs >~ 2 mag).