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arXiv · 2510.19388

Anomalous scattering of pulsars towards the Gum Nebula

M. A. Krishnakumar·Bhal Chandra Joshi·P. K. Manoharan
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Abstract

We report wideband scatter-broadening estimates of 14 pulsars towards the Gum nebula region using the Band-3 of the upgraded GMRT. This work increases the measurements of frequency scaling index of scatter-broadening ($\alpha$) across the nebula by more than 3 times. A strong correlation between the distance and the scattering strength is observed for pulsars behind the nebula. It is also observed that for distant pulsars ($> 2 kpc$), the effect of the Gum nebula in DM and scattering strength is not substantial. We also report a much flatter $\alpha$ for the Vela pulsar and argue that its scattering is not caused by the Gum nebula, but the Vela supernova remnant.

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M. A. Krishnakumar, Bhal Chandra Joshi, P. K. Manoharan. 2025-10-22. Anomalous scattering of pulsars towards the Gum Nebula. https://arxiv.org/abs/2510.19388

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