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The broad OVI absorber at z = 3.02 toward CTQ 325

S. A. Levshakov·S. D'Odorico·I. I. Agafonova·M. Dessauge-Zavadsky
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Abstract

We report on the multiphase absorption-line system detected at a redshift z = 3.021 in the spectrum of the quasi-stellar object CTQ 325 (z_em = 3.212). The system is displaced by ~14,000 km/s to the blue of the systemic velocity defined by the center of the symmetric OI quasar emission line. It consists of shallow and broad (~700 km/s, FWHM) absorption lines of HI 1215, CIV 1548,1550, and OVI 1032,1038, produced by collisionally ionized gas and of narrow absorption lines (FWHM < 20 km/s) of Ly-alpha, Ly-beta, ..., Ly-6, SiIII 1206, and CIII 977 produced by photoionized gas. Possible origins of this system are discussed.

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S. A. Levshakov, S. D'Odorico, I. I. Agafonova, M. Dessauge-Zavadsky. 2003-10-06. The broad OVI absorber at z = 3.02 toward CTQ 325. https://doi.org/10.1051/0004-6361%3A20031559

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