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arXiv · 2506.16687

The Vela pulsar and its pulsar wind nebula Vela-X using 13 years of Fermi-LAT Observations

Alexander Lange·J. Eagle·O. Kargaltsev·Lucien Kuiper·Jeremy Hare
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Abstract

We present results of more than 13 years of Fermi-LAT data analysis for the Vela pulsar from 60 MeV to 100 GeV and its pulsar wind nebula (PWN), Vela-X, for E > 1 GeV in the off-pulse phases. We find the Vela-X PWN can be best characterized using two extended components: a large radial Gaussian accompanied by an off-set, compact radial disk, both with a similar spectral index, Γ\sim 2.3. The common spectral properties support a common PWN origin, but a supernova remnant component is plausible for the compact radial disk. With an updated Vela-X model, the phase resolved spectral properties of the Vela pulsar are explored through a phase-resolved analysis. The phase-resolved spectral properties of the pulsar are presented, such as the SED peak energy E$_p$, the width of the SED at its peak, d$_p$, and the asymptotic (low-energy) spectral index, $Γ_0$, are presented. The best-fit spectral models for each LAT pulse peak (Peak 1 and Peak 2) are extrapolated to UV energies and compared to archival, phase-resolved spectra at UV, X-ray, soft γ-ray and TeV energies. We also discuss the physical implications of our modeling and the data comparisons.

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Alexander Lange, J. Eagle, O. Kargaltsev, Lucien Kuiper, Jeremy Hare. 2025-06-26. The Vela pulsar and its pulsar wind nebula Vela-X using 13 years of Fermi-LAT Observations. https://doi.org/10.3847/1538-4357%2Fade713

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