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arXiv · astro-ph/0107182

Extreme BAL Quasars from the Sloan Digital Sky Survey

Patrick B. Hall·J. E. Gunn·G. R. Knapp·V. K. Narayanan·M. A. Strauss·S. F. Anderson·D. E. Vanden Berk·T. M. Heckman·J. H. Krolik·Z. I. Tsvetanov·W. Zheng·G. T. Richards·D. P. Schneider·X. Fan·D. G. York·T. R. Geballe·M. Davis·R. H. Becker·R. J. Brunner
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Abstract

The Sloan Digital Sky Survey has discovered a population of broad absorption line quasars with various extreme properties. Many show absorption from metastable states of FeII with varying excitations; several objects are almost completely absorbed bluewards of MgII; at least one shows stronger absorption from FeIII than FeII, indicating temperatures T>35000 K in the absorbing region; and one object even seems to have broad H-beta absorption. Many of these extreme BALs are also heavily reddened, though `normal' BALs (particularly LoBALs) from SDSS also show evidence for internal reddening.

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Patrick B. Hall, J. E. Gunn, G. R. Knapp, V. K. Narayanan, M. A. Strauss, S. F. Anderson, D. E. Vanden Berk, T. M. Heckman, J. H. Krolik, Z. I. Tsvetanov, W. Zheng, G. T. Richards, D. P. Schneider, X. Fan, D. G. York, T. R. Geballe, M. Davis, R. H. Becker, R. J. Brunner. 2001-07-10. Extreme BAL Quasars from the Sloan Digital Sky Survey. https://arxiv.org/abs/astro-ph/0107182

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