Poster abstract details

Microlensing of Quasar Broad Emission Lines: Constraints on Broad Line Region Size
Guerras, E., Mediavilla E., Jiménez-Vicente, J., Kochanek, C. S.

Abstract

We use spectra of a sample of 18 quasar image pairs seen through 16 lens galaxies to study the impact of magnification anomalies induced by microlensing on the broad line region (BLR) of quasars.

Superposition of the spectra for each lensed pair images shows excellent matches between the BEL profiles in nearly all cases, whereas a $\sim$ 20\% of them present differences in the overimposed HIL profiles.

We define a test for flux ratio anomalies as the flux ratio in the broad wings relative to the flux ratio in the line core. The resulting histograms indicate a small impact of microlensing in the BELs, though the histogram corresponding to the high ionization lines is broader, with 43\% of the cases having significant anomalous magnifications.

A maximum likelihood statistical analysis, based in the hypothesis that the line core mainly arises from a large region insensitive to microlensing, gives estimates for the BLR sizes for the high and low ionization lines. These cannot be explaind from a virialized disk but they can be reasonably reproduced by a two component kinematic model including an inner virialized disk and an outer radially moving spherical shell.