The multicomponent model of the Crab Pulsar at energies above 25 GeV

We review a proposed multicomponent model to explain the features of the pulsed emission and spectrum of the Crab Pulsar, on the light of the recent detection of pulsed emission above 25 GeV from the MAGIC atmospheric Cherenkov telescope. This model explains the evolution of the pulse shape and of the phase-resolved spectra, ranging from the optical/UV to the GeV energy band, on the assumption that the observed emission is due to several components, which have spectra modelled as log-parabolic laws. We show that the new MAGIC data are well consistent with the prevision of our model.

💡 Research Summary

The paper presents a comprehensive multicomponent model designed to reproduce the complex pulse morphology and phase‑resolved spectra of the Crab Pulsar across an exceptionally broad energy range, from the optical/UV band up to the GeV regime. The authors build on earlier work that employed two spectral components—one dominating the low‑energy (optical–X‑ray) domain and another governing the high‑energy (GeV) domain—but they argue that such a binary description cannot account for the observed evolution of the pulse shape and spectral curvature, especially in the intermediate 10 MeV–100 GeV window.

To overcome this limitation, the model introduces four distinct emission components, labeled C1 through C4. Each component’s differential photon spectrum is described by a log‑parabolic law:

 S(E) = K · (E/E₀)^{‑