Speaker
Description
Several Quantum Gravity models allow for a spontaneous violation of Lorentz Invariance close to the Planck scale, leading to non-trivial energy-dependent dispersion relations for the photon in vacuum. As a result, gamma-rays emitted simultaneously at different energies that travel very long distances can potentially accumulate different measurable delays in their time of flight towards the Earth. In the case of pulsars, such an effect would be revealed as an energy-dependent pulse shift in their phaseogram. The Major Atmospheric Gamma Imaging Cherenkov (MAGIC) Telescopes have been observing the Crab Pulsar since 2004. In this study, we present new constraints on the effective Lorentz Invariance violating energy scale based on a data set with over 300 hours of stereo data collected from 2009 until 2020. Our approach involves a profile likelihood analysis of pulsar events reconstructed with energies ranging from <100 GeV to ~1 TeV. In addition, other characteristics of the Crab Pulsar's emission profile are explored, including an investigation of the intrinsic pulse shape, which could offer new insights into pulsar behaviour at VHE. This study implements an energy-dependent optimisation of the MAGIC standard analysis to improve sensitivity at very high energies, offering a unique opportunity to investigate the long-standing question of a potential TeV extension of the pulsar emission.
