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arXiv · 2301.11549

X-ray studies of the pulsar PSR J1420-6048 and its TeV pulsar wind nebula in the Kookaburra region

Jaegeun Park·Chanho Kim·Jooyun Woo·Hongjun An·Kaya Mori·Stephen P. Reynolds·Samar Safi-Harb
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Abstract

We present a detailed analysis of broadband X-ray observations of the pulsar PSR J1420-6048 and its wind nebula (PWN) in the Kookaburra region with Chandra, XMM-Newton, and NuSTAR. Using the archival XMM-Newton and new NuSTAR data, we detected 68 ms pulsations of the pulsar and characterized its X-ray pulse profile which exhibits a sharp spike and a broad bump separated by ~0.5 in phase. A high-resolution Chandra image revealed a complex morphology of the PWN: a torus-jet structure, a few knots around the torus, one long (~7') and two short tails extending in the northwest direction, and a bright diffuse emission region to the south. Spatially integrated Chandra and NuSTAR spectra of the PWN out to 2.5' are well described by a power law model with a photon index $Γ {\approx}$ 2. A spatially resolved spectroscopic study, as well as NuSTAR radial profiles of the 3--7 keV and 7--20 keV brightness, showed a hint of spectral softening with increasing distance from the pulsar. A multi-wavelength spectral energy distribution (SED) of the source was then obtained by supplementing our X-ray measurements with published radio, Fermi-LAT, and H.E.S.S. data. The SED and radial variations of the X-ray spectrum were fit with a leptonic multi-zone emission model. Our detailed study of the PWN may be suggestive of (1) particle transport dominated by advection, (2) a low magnetic-field strength (B ~ 5$μ$G), and (3) electron acceleration to ~PeV energies.

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Jaegeun Park, Chanho Kim, Jooyun Woo, Hongjun An, Kaya Mori, Stephen P. Reynolds, Samar Safi-Harb. 2023-01-27. X-ray studies of the pulsar PSR J1420-6048 and its TeV pulsar wind nebula in the Kookaburra region. https://doi.org/10.3847/1538-4357%2Facb1b0

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