English

X-ray panorama of the SS433/W50 complex by SRG/eROSITA

High Energy Astrophysical Phenomena 2026-03-25 v2 Astrophysics of Galaxies

Abstract

The Galactic microquasar SS 433 and the radio nebula W50 surrounding it present a prototypical example of a hyper-Eddington binary system shaping its ambient interstellar medium via energetic outflows. In this paper, we present X-ray observations of the SS 433/W50 complex by the eROSITA telescope onboard the \textit{SRG} space observatory. These data provide images of the entire nebula characterized by a very large dynamic range and allow spectral analysis of the diffuse X-ray emission. In particular, these data illustrate a close connection between the thermal and non-thermal components of W50 on scales ranging from sub-parsecs, represented by narrow X-ray bright filaments, to the entire extent of 100pc\gtrsim 100\,{\rm pc} of the nebula. These data also allowed us to fully characterize a pair of nearly symmetric, sharp-edged, elongated structures aligned with the orbital axis of the binary system, which lack radio counterparts but are prominent in very-high-energy gamma-ray emission. The resulting multifaceted picture of the interaction between energetic outflows and the surrounding medium paves the way for future focused multiwavelength observations and dedicated numerical simulations.

Keywords

Cite

@article{arxiv.2510.14938,
  title  = {X-ray panorama of the SS433/W50 complex by SRG/eROSITA},
  author = {Rashid Sunyaev and Ildar Khabibullin and Eugene Churazov and Marat Gilfanov and Pavel Medvedev and Sergey Sazonov},
  journal= {arXiv preprint arXiv:2510.14938},
  year   = {2026}
}

Comments

13+2 pages, 9 figures, accepted to A&A