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arXiv · 2204.13140

Termination Shocks and the Extended X-ray Emission in MRK 78

Francesca M. Fornasini·Martin Elvis·W. Peter Maksym·Giuseppina Fabbiano·Thaisa Storchi Bergmann·Poshak Gandhi·Mark Whittle
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Abstract

Sub-arcsecond imaging of the X-ray emission in the type 2 AGN Mrk 78 with Chandra shows complex structure with spectral variations on scales from $\sim$200 pc to $\sim$ 2 kpc. Overall the X-ray emission is aligned E-W with the radio (3.6 cm) and narrow emission line region as mapped in [OIII], with a marked E-W asymmetry. The Eastern X-ray emission is mostly in a compact knot coincident with the location where the radio source is deflected, while the Western X-ray emission forms a loop or shell $\sim$2 kpc from the nucleus with radius $\sim$0.7 kpc. There is suggestive evidence of shocks in both the Eastern knot and the Western arc. Both these positions coincide with large changes in the velocities of the [OIII] outflow. We discuss possible reasons why the X-ray shocks on the Western side occur $\sim1$ kpc farther out than on the Eastern side. We estimate that the thermal energy injected by the shocks into the interstellar medium corresponds to $0.05-0.6$% of the AGN bolometric luminosity.

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Francesca M. Fornasini, Martin Elvis, W. Peter Maksym, Giuseppina Fabbiano, Thaisa Storchi Bergmann, Poshak Gandhi, Mark Whittle. 2022-04-27. Termination Shocks and the Extended X-ray Emission in MRK 78. https://doi.org/10.3847/1538-4357%2Fac694d

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