Ponente
Descripción
Over the past two decades, the discovery of pulsed very-high-energy (VHE) emission of the Crab pulsar, along with the expansion of the gamma-ray pulsar catalogue driven by the Fermi-LAT satellite, has led to a paradigm shift in the understanding of the gamma-ray emission of pulsars. Once believed to originate near the neutron star’s surface, particle acceleration and radiative processes are now suspected to result from complex magnetopsheric dynamics close to or beyond the pulsar’s light-cylinder. Several theoretical models have been proposed to explain the VHE emission of pulsars, however, distinguishing between them based on observational data has proven challenging.
As one of the youngest known pulsars (~1ka), the Crab hosts extreme electromagnetic processes and its pulsed VHE emission is known to extend up to the TeV range. We present the results of a thorough study of the VHE emission of the Crab pulsar, based on observations from the Fermi-LAT satellite and the MAGIC gamma-ray telescopes. MAGIC is a system of two imaging atmospheric Cherenkov telescopes (IACTs) designed to detect gamma-ray-induced extensive atmospheric showers in the energy range between 20 GeV and 100 TeV. It has been operating since 2004 at the Roque de los Muchachos observatory, on the Canary island of La Palma, Spain. The observations on the Crab pulsar were conducted as part of the commissioning of the Sum-Trigger-II low-energy trigger system and resulted in over 100 hours of good quality data, with a detection of the pulsed emission exceeding the statistical significance of 20σ.
The high-statistics dataset enables a novel phase-resolved spectral analysis, highlighting the evolution of the VHE emission in both energy and time domains. The combined Fermi-LAT and MAGIC observations successfully bridge a statistics gap between 10 GeV and 100 GeV, providing strong evidence for a single inverse-Compton component as the source of the VHE emission. A joint modeling of the spectrum across the entire phase range also imposes stringent constraints on relative energy scale systematics between MAGIC and Fermi-LAT, providing an excellent confirmation of the capabilities of IACTs for gamma-ray pulsar studies. These results constitute a benchmark dataset to test theoretical models of pulsed emission.
