Speaker
Description
On the night of January 19, 2019, the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescope detected GRB 190114C above 0.2 TeV with very high significance, recording by far the most energetic photons ever observed from a gamma-ray burst (GRB). Observations of GRBs can be used to probe an energy dependence of the speed of light in vacuo for photons (in-vacuo dispersion) as predicted by several quantum-gravity models. For the arrival time of high-energy photons from cosmological origin, such a violation of Lorenz Invariance (LIV) could lead to an observably large effect. This makes such observations a rare opportunity to test a relevant parameter space of quantum-gravity predictions. Making use of a set of conservative assumptions on the possible GRB-intrinsic spectral and temporal-evolution and exploiting on a probabilistic basis the full information content of the background-contaminated data set from GRB 190114C, we search for delay of arrival time scaling linearly or quadratically with the energy of the photon.
