Mass and dust in the disk of a spiral lens galaxy
Abstract
Gravitational lensing is a potentially important probe of spiral galaxy structure, but only a few cases of lensing by spiral galaxies are known. We present Hubble Space Telescope and Magellan observations of the two-image quasar PMN J2004-1349, revealing that the lens galaxy is a spiral galaxy. One of the quasar images passes through a spiral arm of the galaxy and suffers 3 magnitudes of V-band extinction. Using simple lens models, we show that the mass quadrupole is well-aligned with the observed galaxy disk. A more detailed model with components representing the bulge and disk gives a bulge-to-disk mass ratio of 0.16 +/- 0.05. The addition of a spherical dark halo, tailored to produce an overall flat rotation curve, does not change this conclusion.
Cite
@article{arxiv.astro-ph/0308093,
title = {Mass and dust in the disk of a spiral lens galaxy},
author = {Joshua N. Winn and Patrick B. Hall and Paul L. Schechter},
journal= {arXiv preprint arXiv:astro-ph/0308093},
year = {2009}
}
Comments
ApJ, in press [9pp, 7 figs]