Student or educator? Sign up with your school email and get 6 months of Pro free.
Cited by 377

The DOI matches its Crossref record; 49 of the 49 references it cites were found in a registry or an index.

Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey

Open access
Hall, Patrick B., Anderson, Scott F., Strauss, Michael A., York, Donald G., Richards, Gordon T., Fan, Xiaohui, Knapp, G. R., Schneider, Donald P., Vanden Berk, Daniel E., Geballe, T. R., Bauer, Amanda E., Becker, Robert H., Davis, Marc, Rix, Hans‐Walter, Nichol, R. C., Bahcall, Neta A., Brinkmann, J., Brunner, Robert, Connolly, A. J., Csabai, Istvan, Doi, Mamoru, Fukugita, Masataka, Gunn, James E., Haiman, Zoltan, Harvanek, Michael, Heckman, Timothy M., Hennessy, G. S., Inada, Naohisa, Ivezić, Željko, Johnston, David, Kleinman, S., Krolik, Julian H., Krzesinski, Jurek, Kunszt, Peter Z., Lamb, D. Q., Long, Daniel C., Lupton, Robert H., Miknaitis, Gajus, Munn, Jeffrey A., Narayanan, Vijay K., Neilsen, Eric, Newman, P. R., Nitta, Atsuko, Okamura, Sadanori, Pentericci, Laura, Pier, Jeffrey R., Schlegel, David J., Snedden, S., Szalay, Alexander S., Thakar, Anirudda R., Tsvetanov, Zlatan, White, Richard L., Zheng, Wei·2002·The Astrophysical Journal Supplement Series

Abstract

The Sloan Digital Sky Survey has confirmed the existence of populations of broad absorption line (BAL) quasars with various unusual properties. We present and discuss 23 such objects and consider the implications of their wide range of properties for models of BAL outflows and quasars in general. We have discovered one BAL quasar with a record number of absorption lines. Two other similarly complex objects with many narrow troughs show broad Mg II absorption extending longward of their systemic host galaxy redshifts. This can be explained as absorption of an extended continuum source by the rotation-dominated base of a disk wind. Five other objects have absorption that removes an unprecedented ∼90% of all flux shortward of Mg II. The absorption in one of them has varied across the ultraviolet with an amplitude and rate of change as great as ever seen. This same object may also show broad Hβ absorption. Numerous reddened BAL quasars have been found, including at least one reddened mini-BAL quasar with very strong Fe II emission. The five reddest objects have continuum reddenings of E ( B - V ) ≃ 0.5, and in two of them we find strong evidence that the reddening curve is even steeper than that of the SMC. We have found at least one object with absorption from Fe III but not Fe II. This may be due to a high column density of moderately high ionization gas, but the Fe III level populations must also be affected by some sort of resonance. Finally, we have found two luminous, probably reddened high-redshift objects that may be BAL quasars whose troughs partially cover different regions of the continuum source as a function of velocity.

Overview

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1086/340546

Cites

49 of 49 references verified0 citation errors · 0 not checkable

Statistics

Verification

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Citations

Cites

Show all 49 references

Cited by

See all 377

Metadata

Authors
Hall, P. B., Anderson, S. F., Strauss, M. A., York, D. G., Richards, G. T., Fan, X., Knapp, G. R., Schneider, D. P., Vanden Berk, D. E., Geballe, T. R., Bauer, A. E., Becker, R. H., Davis, M., Rix, H., Nichol, R. C., Bahcall, N. A., Brinkmann, J., Brunner, R., Connolly, A. J., Csabai, I., Doi, M., Fukugita, M., Gunn, J. E., Haiman, Z., Harvanek, M., Heckman, T. M., Hennessy, G. S., Inada, N., Ivezić, Ž., Johnston, D., Kleinman, S., Krolik, J. H., Krzesinski, J., Kunszt, P. Z., Lamb, D. Q., Long, D. C., Lupton, R. H., Miknaitis, G., Munn, J. A., Narayanan, V. K., Neilsen, E., Newman, P. R., Nitta, A., Okamura, S., Pentericci, L., Pier, J. R., Schlegel, D. J., Snedden, S., Szalay, A. S., Thakar, A. R., Tsvetanov, Z., White, R. L., & Zheng, W.
Venue
The Astrophysical Journal Supplement Series
Published
2002-08
Volume
141
Issue
2
Pages
267-309
ISSN
  • 0067-0049 (ISSN-L)
  • 1538-4365
OpenAlex
W2044610256
Cited by
377
References
49
FWCI
9.73
Type
journal article
Language
en
Open access
green

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review

How to cite

Cite CoChat for the checks on this page, and the paper for its own findings.

This page
CoChat. (2026). Citation check: Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey. https://app.cochat.ai/papers/10.1086/340546
The paper
Hall, P. B., Anderson, S. F., Strauss, M. A., York, D. G., Richards, G. T., Fan, X., Knapp, G. R., Schneider, D. P., Vanden Berk, D. E., Geballe, T. R., Bauer, A. E., Becker, R. H., Davis, M., Rix, H., Nichol, R. C., Bahcall, N. A., Brinkmann, J., Brunner, R., Connolly, A. J., . . . Zheng, W. (2002). Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey. The Astrophysical Journal Supplement Series. https://doi.org/10.1086/340546

Data sources

Bibliographic data: Semantic Scholar, OpenAlex, Crossref.

Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.