Saved in:
Bibliographic Details
Main Authors: Guo, YingYing, Yuan, Qiang
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2407.10705
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914871879139328
author Guo, YingYing
Yuan, Qiang
author_facet Guo, YingYing
Yuan, Qiang
contents The extended $γ$-ray halos around pulsars are unique probe of transportation of high-energy electrons (and positrons) in vicinities of such pulsars. Observations of morphologies of several such halos indicate that particles diffuse very slowly around pulsars, compared with that in the Milky Way halo. The energy-dependent morphologies are expected to be very important in studying the energy-dependence of the diffusion coefficient. In this work we point out that the spectrum of high-energy electrons takes effect in shaping the $γ$-ray morphologies at the ultra-high-energy bands, and thus results in a degeneracy between the electron spectrum and the energy-dependence of the diffusion coefficient. The reasons for such a degeneracy include both the Klein-Nishina effect of the inverse Compton scattering and the curvature (if any) of the electron spectrum. It it thus necessary to take into account the spectral shape of electrons when deriving the energy-dependence of diffusion coefficient using ultra-high-energy $γ$-ray measurements of extended pulsar halos.
format Preprint
id arxiv_https___arxiv_org_abs_2407_10705
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Impact of electron spectra on morphology of pulsar halos at ultra-high energies
Guo, YingYing
Yuan, Qiang
High Energy Astrophysical Phenomena
The extended $γ$-ray halos around pulsars are unique probe of transportation of high-energy electrons (and positrons) in vicinities of such pulsars. Observations of morphologies of several such halos indicate that particles diffuse very slowly around pulsars, compared with that in the Milky Way halo. The energy-dependent morphologies are expected to be very important in studying the energy-dependence of the diffusion coefficient. In this work we point out that the spectrum of high-energy electrons takes effect in shaping the $γ$-ray morphologies at the ultra-high-energy bands, and thus results in a degeneracy between the electron spectrum and the energy-dependence of the diffusion coefficient. The reasons for such a degeneracy include both the Klein-Nishina effect of the inverse Compton scattering and the curvature (if any) of the electron spectrum. It it thus necessary to take into account the spectral shape of electrons when deriving the energy-dependence of diffusion coefficient using ultra-high-energy $γ$-ray measurements of extended pulsar halos.
title Impact of electron spectra on morphology of pulsar halos at ultra-high energies
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2407.10705