Probing Lorentz Invariance Violation with energy-resolved gamma-ray burst timing
Lecturer: Wladimiro Leone, University of Palermo (Italy)
Abstract:
Quantum gravity theories suggest that, at energies close to the Planck scale, the structure of space-time may deviate from the smooth picture described by general relativity. One possible observational signature is a tiny energy-dependent delay in the arrival times of photons travelling over cosmological distances.
Gamma-ray bursts are ideal laboratories to search for this effect: they are extremely energetic, rapidly variable, and can be observed up to very high energies. In this seminar, I will present an energy-resolved timing method to test Lorentz Invariance Violation using gamma-ray bursts with known redshift.
The key idea is to model the observed time lag as the combination of two contributions: an intrinsic delay related to the GRB emission process, and a possible propagation-induced delay accumulated during the photon journey through the Universe.
I will show the application of this method to 26 Fermi GRBs observed by GBM and LAT, covering the redshift range 0.36<z<4.35. For a linear sub-luminal LIV correction, we obtain a lower limit for the quantum gravity energy scale: EQG,1>3.3× 10-2 EPl at 95% confidence level.
Wednesday, 10 June, 12:10 at Seminario Física Nuclear or online