An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines

Abstract

We present graphically the results of several thousand photoionization calculations of broad emission line clouds in quasars, spanning seven orders of magnitude in hydrogen ionizing flux and particle density. The equivalent widths of 42 quasar emission lines are presented as contours in the particle density - ionizing flux plane for a typical incident continuum shape, solar chemical abundances, and cloud column density of $N(H) = 10^{23} cm^{-2}$. Results are similarly given for a small subset of emission lines for two other column densities ($10^{22} cm^{-2}$ and $10^{24} cm^{-2}$), five other incident continuum shapes, and a gas metallicity of 5 \Zsun. These graphs should prove useful in the analysis of quasar emission line data and in the detailed modeling of quasar broad emission line regions. The digital results of these emission line grids and many more are available over the Internet.