Brian Moloney

My PhD project concerns the nature of so-called "intraday variability," or variability on times scales less than a day, in AGN. There is considerable debate about whether this variability most often has an intrinsic origin, indicating very high brightness temperatures in the varying regions, or an extrinsic origin, due to propagation effects such as scintillation in the interstellar medium. I am analyzing VLBI polarization data for the scintillating quasar J1819+3845, as well as for a number of AGN whose intraday variability may include a substantial intrinsic component.