Classifying optical spectra of high-redshift quasars

The most distant quasars provide important clues to the formation of supermassive black holes at the early Universe.  First data for those quasars are usually discovery spectra in the rest-frame UV band, taken by optical telescopes. They contain a few imprints of nuclear activities, such as outflows, as well as Lyman alpha emission for determining their redshifts. The SHELLQs project using the Subaru HSC survey discovered more than 160 quasars, mainly in the lower-luminosity regime, at redshift ranging from 5.7 to 7.1, corresponding to the epoch ~1 Gyr after the Big Bang. The data of their discovery spectra are available and their shapes could be grouped into a limited number of types. The main task is to classify these spectra and identify the most important feature to characterise each type. At the same time, a student is expected to learn  the basic knowledge of quasars: how the large energy output of quasars is generated, how those high-redshift quasars can be discovered, what are the important questions to be answered as to the formation of supermassive black holes.