Teraelectronvolt pulsed emission from the Crab pulsar detected by MAGIC

TL;DR

This paper reports the detection of the most energetic pulsed emission from the Crab pulsar up to 1.5 TeV, revealing new insights into its high-energy spectral tail and emission mechanisms.

Contribution

First detection of pulsed emission from the Crab pulsar at energies up to 1.5 TeV using MAGIC, extending the known spectral tail and providing constraints on emission models.

Findings

Pulsed emission detected up to 1.5 TeV.

Spectral peaks follow different power-law functions.

Emission likely due to inverse Compton scattering near the light cylinder.

Abstract

Aims: To investigate the extension of the very-high-energy spectral tail of the Crab pulsar at energies above 400 GeV. Methods: We analyzed $\sim$320 hours of good quality data of Crab with the MAGIC telescope, obtained from February 2007 until April 2014. Results: We report the most energetic pulsed emission ever detected from the Crab pulsar reaching up to 1.5 TeV. The pulse profile shows two narrow peaks synchronized with the ones measured in the GeV energy range. The spectra of the two peaks follow two different power-law functions from 70 GeV up to 1.5 TeV and connect smoothly with the spectra measured above 10 GeV by the Large Area Telescope (LAT) on board of the Fermi satellite. When making a joint fit of the LAT and MAGIC data, above 10 GeV, the photon indices of the spectra differ by 0.5$\pm$0.1. Conclusions: We measured with the MAGIC telescopes the most energetic pulsed photons from a pulsar to date. Such TeV pulsed photons require a parent population of electrons with a Lorentz factor of at least $5\times 10^6$. These results strongly suggest IC scattering off low energy photons as the emission mechanism and a gamma-ray production region in the vicinity of the light cylinder.