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arXiv · 2506.22409

NuSTAR and XMM-Newton Observations of PSR J1930+1852 and Its Pulsar Wind Nebula

J. A. J. Alford·G. -B. Zhang·J. D. Gelfand
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Abstract

Synchrotron X-ray emission from a pulsar wind nebula (PWN) is a sensitive probe of its magnetic field and high-energy particle population. Here we analyze contemporaneous NuSTAR and XMM-Newton observations of the PWN G54.1+0.3, powered by pulsar PSR J1930+1852. We also present a preliminary timing analysis of the central pulsar PSR J1930+1852 and analyze its X-ray pulse profiles in different energy bands. We detect X-ray emission from the combined pulsar and PWN system up to $\approx70$ keV, while emission from the PWN itself has been detected up to $\approx30$ keV, with a photon index $\Gamma$ increasing from $\sim 1.9$ to $\sim 2.4$ with photon energy between 3 and 30 keV. PWN G54.1+0.3's X-ray spectrum is consistent with a broken power law, with break energy $E_{\rm break} \approx 5$ keV, consistent with synchrotron cooling of a single power-law particle spectrum. The best-fit broadband spectral energy distribution model after the inclusion of this new spectral data indicates a maximum particle $E_{\rm max} \sim 400$ TeV. We discuss PSR J1930+1852 and PWN G54.1+0.3 in the context of other PWNe powered by young energetic pulsars.

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J. A. J. Alford, G. -B. Zhang, J. D. Gelfand. 2025-06-27. NuSTAR and XMM-Newton Observations of PSR J1930+1852 and Its Pulsar Wind Nebula. https://doi.org/10.3847/1538-4357%2Fadd92e

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