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arXiv · 2205.12285

Coordinated time variability of multi-phase ultra-fast outflows in J132216.25+052446.3

P. Aromal·R. Srianand·P. Petitjean
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Abstract

We present a time variability analysis of broad absorption lines (BAL; spread over the velocity range of 5800-29000 km/s) seen in the spectrum of J132216.25+052446.3 (z(em)= 2.04806) at ten different epochs spanning over 19 years. The strongest absorption component (BAL-A; spread over 5800-9900 km/s) is made up of several narrow components having velocity separations close to C IV doublet splitting. The C IV, N V, and Si IV absorption from BAL-A show correlated optical depth variability without significant changes in the velocity structure. A very broad and shallow absorption (BAL-C; spread over the velocity range 15000-29000 km/s) emerged during our monitoring period coinciding with a dimming episode of J1322+0524. All the identified absorption lines show correlated variability with the equivalent widths increasing with decreasing flux. This together with the C IV emission-line variability is consistent with ionization being the main driver of the correlated variability. The observed UV-continuum variations are weaker than what is required by the photo-ionization models. This together with a scatter in the C iv equivalent width at a given continuum flux can be understood if variations of the C IV ionizing photons are much larger than that of the UV continuum, the variations in the ionizing photon and UV fluxes are not correlated and/or the covering factor of the flow varies continuously. We suggest BAL-A is produced by a stable clumpy outflow located beyond the broad emission line region and BAL-C is a newly formed wind component located near the accretion disk and both respond to changes in the ionizing continuum.

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P. Aromal, R. Srianand, P. Petitjean. 2022-05-24. Coordinated time variability of multi-phase ultra-fast outflows in J132216.25+052446.3. https://doi.org/10.1093/mnras%2Fstac1460

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