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摘要
We study winds in 12 X-ray AGN host galaxies at z similar to 1. We find, using the low-ionization Fe II lambda 2586 absorption in the stacked spectra, that the probability distribution PDF) of the centroid-velocity shift in AGNs has. 50th (median), 16th, and 84th percentiles of (87, 251, | 86) km s(-1) respectively. The PDF of the velocity dispersion in AGNs has 50th (median), 84th, and 16th percentiles of (139, 253, 52) km s(-1) respectively. The centroid velocity and the velocity dispersions are obtained from a two-component (ISM+ wind) absorption-line model. The equivalent width PDF of the outflow in AGNs has. 50th (median), 84th, and 16th percentiles. of (0.4, 0.8, 0.1) angstrom. There is a strong ISM component in Fe II lambda 2586 absorption (with (1.2, 1.5, 0.8) angstrom, implying the. presence of a. substantial amount cold gas in the host galaxies. For comparison, star-forming and X-ray. undetected galaxies at a similar redshift, matched roughly in stellar mass and galaxy inclination, have a centroid-velocity PDF with percentiles of (-74, -258, +90) km s(-1), and a. velocity-dispersion PDF with. percentiles of (150, 259, 57) km s(-1). Thus, winds in the AGN are similar to star formation-driven winds, and are too weak to escape and expel substantial cool gas from galaxies. Our sample doubles the previous sample of AGNs. studied at z similar to 0.5 and extends the analysis to z similar to 1. A joint reanalysis of the z similar to 0.5 AGN sample and our sample yields consistent results to the measurements above.
- 出版日期2017-6-1
- 单位沈阳师范大学
