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arXiv · astro-ph/0308093

Mass and dust in the disk of a spiral lens galaxy

Joshua N. Winn·Patrick B. Hall·Paul L. Schechter
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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.

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Joshua N. Winn, Patrick B. Hall, Paul L. Schechter. 2003-08-06. Mass and dust in the disk of a spiral lens galaxy. https://doi.org/10.1086/378637

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