An XMM-Newton EPIC X-ray view of the Symbiotic Star R~Aquarii

TL;DR

This study uses XMM-Newton X-ray observations to reveal detailed diffuse soft X-ray emission around the symbiotic star R Aquarii, showing a bipolar morphology linked to jet activity and hot gas bubbles.

Contribution

First detailed X-ray imaging of R Aquarii revealing diffuse emission and jet-related structures, illustrating jet feedback mechanisms in evolved binary star systems.

Findings

Diffuse soft X-ray emission extends up to 0.27 pc from R Aquarii.

Bipolar X-ray morphology correlates with optical nebula.

Evidence of hot gas bubbles created by jet activity.

Abstract

We present the analysis of archival XMM-Newton European Photon Imaging Camera (EPIC) X-ray observations of the symbiotic star R Aquarii. We used the Extended Source Analysis Software (ESAS) package to disclose diffuse soft X-ray emission extending up to 2.2 arcmin ($\approx$0.27 pc) from this binary system. The depth of these XMM-Newton EPIC observations reveal in unprecedented detail the spatial distribution of this diffuse emission, with a bipolar morphology spatially correlated with the optical nebula. The extended X-ray emission shares the same dominant soft X-ray-emitting temperature as the clumps in the jet-like feature resolved by Chandra in the vicinity of the binary system. The harder component in the jet might suggest that the gas cools down, however, the possible presence of non-thermal emission produced by the presence of a magnetic field collimating the mass ejection can not be discarded. We propose that the ongoing precessing jet creates bipolar cavities filled with X-ray-emitting hot gas that feeds the more extended X-ray bubble as they get disrupted. These EPIC observations demonstrate that the jet feedback mechanism produced by an accreting disk around an evolved, low-mass star can blow hot bubbles, similar to those produced by jets arising from the nuclei of active galaxies.