English

Multi-wavelength Study of HESS J0632+057: New Insights into Pulsar-Disk Interaction

High Energy Astrophysical Phenomena 2025-08-01 v1

Abstract

We present an analysis of new multi-wavelength observations of the TeV gamma-ray binary HESS J0632+057, conducted using SALT, Swift, NuSTAR, and VERITAS in 2023--2024. By combining these new data with archival observations, we confirm previous suggestions of orbital variability in the source's X-ray spectrum, including increased X-ray absorption at the orbital phase interval of ϕ0.30.4\phi\approx0.3\textrm{--}0.4. The source's X-ray flux within this phase interval seems to have exhibited a significant change on an orbital timescale. Additionally, occasional short-term variations in the X-ray band on a timescale of less than 3 days have been observed. The measured duration of the increased absorbing column density and the flux variability timescales can provide clues about the interaction between the putative pulsar and the Be companion's disk if, as previously suggested, the pulsar crosses the disk at this phase interval. Moreover, the new contemporaneous X-ray and TeV observations around the pulsar-crossing phases revealed independent variability in the X-ray and TeV fluxes, contrary to a previous observation of concurrent flux increases. While these observations alone cannot provide definitive conclusions, we discuss our results in the context of pulsar-disk interaction and intrabinary shock emission scenarios.

Keywords

Cite

@article{arxiv.2507.23304,
  title  = {Multi-wavelength Study of HESS J0632+057: New Insights into Pulsar-Disk Interaction},
  author = {Jaegeun Park and Hongjun An and Chanho Kim and Natalie Matchett and Kaya Mori and Brian van Soelen and VERITAS Collaboration and : and A. Archer and P. Bangale and J. T. Bartkoske and W. Benbow and J. H. Buckley and Y. Chen and A. J. Chromey and A. Duerr and M. Errando and M. Escobar Godoy and A. Falcone and S. Feldman and Q. Feng and S. Filbert and L. Fortson and A. Furniss and W. Hanlon and O. Hervet and C. E. Hinrichs and J. Holder and T. B. Humensky and W. Jin and M. N. Johnson and P. Kaaret and M. Kertzman and M. Kherlakian and D. Kieda and T. K. Kleiner and N. Korzoun and S. Kumar and M. J. Lang and M. Lundy and G. Maier and P. Moriarty and R. Mukherjee and M. Ohishi and R. A. Ong and A. Pandey and M. Pohl and E. Pueschel and J. Quinn and P. L. Rabinowitz and K. Ragan and D. Ribeiro and E. Roache and I. Sadeh and L. Saha and G. H. Sembroski and R. Shang and J. V. Tucci and V. V. Vassiliev and A. Weinstein and D. A. Williams and S. L. Wong and T. Yoshikoshi},
  journal= {arXiv preprint arXiv:2507.23304},
  year   = {2025}
}

Comments

15 pages, 7 figures. Accepted for publication in ApJ