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arXiv · 1808.08204

A stratified ultrafast outflow in 1H0707-495?

P. Kosec·D. J. K. Buisson·M. L. Parker·C. Pinto·A. C. Fabian·D. J. Walton
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Abstract

Ultrafast outflows (UFOs) have recently been found in the spectra of a number of active galactic nuclei (AGN) and are strong candidates for driving AGN feedback. 1H0707-495 is a highly accreting narrow line Seyfert 1 and the second most X-ray variable bright AGN. Previous studies found evidence of blueshifted absorption at 0.1-0.2c in its spectrum. We perform a flux-resolved analysis of the full XMM-Newton dataset on this AGN using both CCD and grating data, focusing on the low flux spectrum. We find strong evidence for an ultrafast outflow in absorption at $\sim$0.13c, with an ionisation parameter $\log(\xi$/erg cm s$^{-1})=4.3$. Surprisingly, we also detect blueshifted photoionised emission, with the velocity increasing at higher ionisation states, consistent with a trend that has been observed in the UV spectrum of this object. The bulk of the X-ray emitting material is moving at a velocity of 8000 km/s, with ionisation parameter $\log(\xi$/erg cm s$^{-1})=2.4$. The wind kinetic power inferred from the UFO absorption is comparable to that of the UV and X-ray emission features despite their different velocities and ionisation states, suggesting that we are viewing an energy-conserving wind slowing down and cooling at larger distances from the AGN.

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P. Kosec, D. J. K. Buisson, M. L. Parker, C. Pinto, A. C. Fabian, D. J. Walton. 2018-08-24. A stratified ultrafast outflow in 1H0707-495?. https://doi.org/10.1093/mnras%2Fsty2342

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