Liliya L.R. Williams of University of Minnesota, Astronomy Dept., Tate Lab of Physics will be visiting DARK 27-28 November and will give a talk entitled "A new statistical evidence for substructure in lensing galaxies?".

 

Date: Thurs. 27 November 2008

Time: 14:15

Place: DARK lounge

 

The abstract:

"I will introduce a novel statistical way of analyzing the projected mass distribution in galaxy lenses based solely on the angular distribution of images in quads around the lens center. I will show that all lenses with two-fold symmetric mass distribution are identical when their angular image structure is considered. I will also show that lenses with twisting isodensity contours, lumpy substructure, etc. have a different signature. The results may suggest that in the observed quad population kpc-scale mass substructure in lenses is common."