# NEW CONSTRAINTS ON THE QUASAR BROAD EMISSION LINE REGION

@article{Ruff2012NEWCO,
title={NEW CONSTRAINTS ON THE QUASAR BROAD EMISSION LINE REGION},
author={Andrea J. Ruff and David J. E. Floyd and R. L. Webster and K. T. Korista and Hermine Landt},
journal={The Astrophysical Journal},
year={2012},
volume={754},
pages={18}
}
• Published 4 June 2012
• Physics
• The Astrophysical Journal
We demonstrate a new technique for determining the physical conditions of the broad-line-emitting gas in quasars, using near-infrared hydrogen emission lines. Unlike higher ionization species, hydrogen is an efficient line emitter for a very wide range of photoionization conditions, and the observed line ratios depend strongly on the density and photoionization state of the gas present. A locally optimally emitting cloud model of the broad emission line region was compared to measured emission…
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