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arXiv · 2011.14768

Frequency resolved radio and high-energy emission of pulsars

Abstract

Context. Pulsars are detected as broadband electromagnetic emitters from the radio wavelength up to high and very high energy in the MeV/GeV and sometimes even in the TeV range. Multi-wavelength phase-resolved spectra and light curves offer an unrivalled opportunity to understand their underlying radiation mechanisms and to localize their emission sites and therefore the particle acceleration regions. Aims. In this paper, we compute pulsars multi-wavelength phase-resolved light-curves and spectra assuming that curvature radiation operates from inside the magnetosphere of a rotating vacuum magnet. Radio emission arises from the polar caps whereas gamma-ray energy emanates from the slot gaps in the vicinity of the separatrix between closed and open field lines. Methods. By integrating particle trajectories within the slot gaps, we compute energy dependent photon sky maps in the radio band (MHz-GHz) and in the gamma-ray band (MeV/GeV) for mono-energetic distribution functions of leptons. Results. We obtained many details of the energy dependent light curves and phase-resolved spectra from the radio wavelength up to the gamma-ray energies. Choosing Lorentz factors of {\gamma} = 30 for radio emitting particles and {\gamma} = 10^7 for gamma-ray emitting particles, we found realistic spectra accounting for the wealth of multi-wavelength pulsar observations.

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Quentin Giraud, Jérôme Pétri. 2020-11-30. Frequency resolved radio and high-energy emission of pulsars. https://doi.org/10.1051/0004-6361/202040020

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