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arXiv · 2202.08405

UV counterpart of an X-ray ultra-fast outflow in IRAS 17020+4544

Missagh Mehdipour·Gerard A. Kriss·Yair Krongold·Anna Lia Longinotti·Elisa Costantini·Anjali Gupta·Smita Mathur·Fabrizio Nicastro·Francesca Panessa·Debopam Som
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Abstract

We report on the discovery of a UV absorption counterpart of a low-ionization X-ray ultra-fast outflow (UFO) in the Narrow-Line Seyfert-1 galaxy IRAS 17020+4544. This UV signature of the UFO is seen as a narrow and blueshifted Lyman-alpha absorption feature in the far-UV spectrum, taken with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST). The Lyman-alpha feature is found to be outflowing with a velocity of -23430 km/s (0.078 c). We carry out high-resolution UV spectroscopy and photoionization modeling to study the UFO that is seen in the HTS/COS spectrum. The results of our modeling show that the UV UFO corresponds to a low-ionization, low-velocity component of the X-ray UFO found previously with XMM-Newton's Reflection Grating Spectrometer (RGS). The other higher-velocity and higher-ionization components of the X-ray UFOs are not significantly detected in the HST/COS spectrum, consistent with predictions of our photoionization calculations. The multiple ionization and velocity components of the UFOs in IRAS 17020+4544 suggest a scenario where a powerful primary UFO entrains and shocks the ambient medium, resulting in formation of weaker secondary UFO components, such as the one found in the UV band.

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Missagh Mehdipour, Gerard A. Kriss, Yair Krongold, Anna Lia Longinotti, Elisa Costantini, Anjali Gupta, Smita Mathur, Fabrizio Nicastro, Francesca Panessa, Debopam Som. 2022-02-17. UV counterpart of an X-ray ultra-fast outflow in IRAS 17020+4544. https://doi.org/10.3847/1538-4357%2Fac5681

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