|Title||Non-forward shock components in X-ray afterglows|
|Author||Dr Massimiliano De Pasquale|
|Description||In the Forward Shock (FS) model, the GRB afterglow is produced in the circumburst medium when the ejecta interacts with it. However, a few GRBs have an X-ray lightcurve with a very large change of decay slope, that is hard to explain by a FS, while their optical behaviour is different and more consistent with it. One proposed solution is that X-ray emission is produced within the ejecta, and ends in a few ks. We propose to test this scenario by observing at late epochs 2 GRBs with a large break in the X-ray lightcurve and detected optical afterglow with XMM-Newton. In this model, the X-ray flux at late epochs should return to a shallower decay, similar to the optical, when the emission from the FS prevails. XMM-Newton high sensitivity is required to constrain the X-ray flux at late times.|
|Publication||No observations found associated with the current proposal|
|Instrument||EMOS1, EMOS2, EPN, OM, RGS1, RGS2|
|Mission Description||The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's 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 Earth's 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.
|Publisher And Registrant||European Space Agency|
|Credit Guidelines||European Space Agency, 2014-07-03T00:00:00Z, 069338, 17.56_20190403_1200. https://doi.org/10.5270/esa-vh51ryu|