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arXiv · 2212.11426

GeV gamma-ray emission from pulsar wind nebula HESS J1356-645 with Fermi-LAT

Xi Liu·Xiaolei Guo·Yuliang Xin·Fengrong Zhu·Siming Liu
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Abstract

HESS J1356-645 is considered to be a pulsar wind nebula (PWN) associated with the pulsar PSR J1357-6429. We reanalyze the GeV gamma-ray emission in the direction of HESS J1356-645 with more than 13 years of Fermi Large Area Telescope (LAT) data. The extended gamma-ray emission above 5 GeV is found to be spatially coincident with HESS J1356-645. The spectrum in the energy range of 1 GeV-1 TeV can be described by a power law with an index of $\Gamma=1.51\pm0.10$. The broadband spectrum of HESS J1356-645 can be reproduced by a leptonic model with a broken power-law electronic spectrum. In addition, we found evidence that the morphology of the GeV emission from HESS J1356-645 varies with energy, a behavior which is similar to that of the PWN Vela-X. More broadband observations will be helpful to study the energy-dependent characteristics of HESS J1356-645.

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Xi Liu, Xiaolei Guo, Yuliang Xin, Fengrong Zhu, Siming Liu. 2022-12-22. GeV gamma-ray emission from pulsar wind nebula HESS J1356-645 with Fermi-LAT. https://doi.org/10.3847/1538-4357%2Faca96b

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