Quasar Atmospheres: Toward a "Low" Theory for Quasars

Abstract

After 40 years we have no "low" theory of quasars to predict the atomic absorption and emission features so abundant in quasar spectra. Here I take the first step, using results selected for their diagnostic power to build an "observational paradigm" unifying all the atomic features in quasars. This paradigm bears a remarkable resemblance to the one I proposed in Elvis (2000, astro-ph/0008064)! Yet all the results used here were not used in that earlier study, with one exception. The Elvis (2000) model has been tested by the new data and has survived, and so has been strengthened. The structure is readily tested, is physically suggestive, and opens up many areas for detailed modelling. From this I believe a truly predictive "low" theory of quasars will emerge.