On the origin of the X-ray emission surrounding PSR B0656+14 in the eROSITA Cal-PV data

Abstract

We present a cautionary assessment of the extended X-ray emission around PSR B0656+14 in eROSITA Cal-PV data in response to the work of Niu et al. 2025 (arXiv:2501.17046). The eROSITA PSF model is known to underestimate emission in the wings beyond 1'. This prevents a reliable detection of faint nebular emission around PSR B0656+14 as claimed in arXiv:2501.17046. In addition, spectral analysis shows the surrounding diffuse X-rays can be fitted with the same 2BB+PL model as the pulsar's emission itself. This strongly invalidates the interpretation by the authors of arXiv:2501.17046 that the X-ray emission in the (4-10)' region is associated with the degree-scale gamma-ray halo recently found by the High-Altitude Water Cherenkov Observatory (HAWC), and shows that it originates from the pulsar due to the wings of the PSF.

3 pages, 1 figure. Published in RNAAS

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Cited by in corpus (2)

• PHECT: A lightweight computation tool for pulsar halo emission
• Possible evidence for extended X-ray emission surrounding PSR B0656+14 with eROSITA