The most extreme GRBs radiate equivalent isotropic energies close to 10^54 erg;energies which cannot be accommodated in core-collapse models. Thus GRBs arethought to be narrowly beamed, which should give rise to an achromatic lightcurve break as the outflow slows and the Doppler beaming angle becomes of thesame order as the jet opening angle. However, observations with Swift suggestsuch jet breaks are absent, leading to concerns about the total energetics whichmay undermine the entire GRB paradigm. We seek XMM-Newton observations to testfor the absence of breaks in the X-ray light curves of two highly energeticGRBs. If even one is found with no break at late times, then the whole class ofcore-collapse models for GRBs will be thrown into serious doubt.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2008-08-12T09:12:15Z/2008-08-27T15:52:09Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Dr Rhaana Starling, 2009, 'A fundamental test of the fireball model for GRBs', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-dap6com
