An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines

We present graphically the results of several thousand photoionization calculations of broad emission-line clouds in quasars, spanning 7 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 and 10 24 cm -2 ), five other incident continuum shapes, and a gas metallicity of 5 Z ☉ . 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.