English

Narrow UV Absorption Line Outflows from Quasars

Cosmology and Nongalactic Astrophysics 2012-04-18 v1

Abstract

Narrow absorption line (NAL) outflows are an important yet poorly understood part of the quasar outflow phenomenon. We discuss one particular NAL outflow that has high speeds, time variability, and moderate ionizations like typical BAL flows, at an estimated location just ~5 pc from the quasar. It also has a total column density and line widths (internal velocity dispersions) ~100 times smaller than BALs, with no substantial X-ray absorption. We argue that radiative shielding (in the form of an X-ray/warm absorber) is not critical for the outflow acceleration and that the moderate ionizations occur in dense substructures that have an overall small volume filling factor in the flow. We also present new estimates of the overall incidence of quasar outflow lines; e.g., ~43% of bright quasars have a C IV NAL outflow while ~68% have a C IV outflow line of any variety (NAL, BAL, or mini-BAL).

Keywords

Cite

@article{arxiv.1204.3791,
  title  = {Narrow UV Absorption Line Outflows from Quasars},
  author = {Fred Hamann and Leah Simon and Paola Rodriguez Hidalgo and Daniel Capellupo},
  journal= {arXiv preprint arXiv:1204.3791},
  year   = {2012}
}

Comments

5 pages, proceedings for the conference "AGN Winds in Charleston", Charleston, S.C., 2011

R2 v1 2026-06-21T20:50:45.519Z