Master Thesis Defense by Christopher Nick Andersen

Title: Extremely Detached BAL Quasars

Abstract:

The Unified model for quasars is an attempt at describing the many different types of quasars based on as few physical parameters as possible. But the discovery of the unusual spectrum observed from the BAL quasar Q1309+2904, and the subsequent observation of SDSSJ101230.16+035856.8 may lead to another addition of this model. Despite both objects lack of emission lines, for the case of SDSSJ101230 both Hα and extended Lyman-α was observed and used to determine a redshift each differing only around 0.002 in value, therefor settling on the median value of z = 2.1747 for SDSSJ101230. In the case of Q1309+2904, a redshift of z = 2.66 was found after using the peak of the extended Lyman emission, with their observations supporting a redshift of z = 2.66. The observations of these two cases neither confirms nor deny whether this is a rare case or perhaps a new type of quasar and how it will fit into the unified model. But it has sparked some interest as a future topic of research.

Supervisor:

• Johan Peter Uldall Fynbo, University of Copenhagen, Niels Bohr Institute

Censor:

• Frank Grundahl, Aarhus University