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The Time Delays of Gravitational Lens HE0435-1223: An Early-Type Galaxy With a Rising Rotation Curve

C. S. Kochanek·N. D. Morgan·E. E. Falco·B. A. McLeod·J. N. Winn·J. Dembicky·B. Ketzeback
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Abstract

We present Hubble Space Telescope images and 2 years of optical photometry of the quadruple quasar HE0435-1223. The time delays between the intrinsic quasar variations are 14.4+/-0.8 (A-D), 8.0+/-0.8 (A-B) and 2.1+/-0.8 (A-C) days. We also observed non-intrinsic variations of ~0.1 mag/yr that we attribute to microlensing. Instead of the traditional approach of assuming a rotation curve for the lens galaxy and then deriving the Hubble constant (H_0), we assume H_0=(72+/-7) km/s/Mpc and derive constraints on the rotation curve. On the scale over which the lensed images occur (1.2"=5kpc/h=1.5R_e), the lens galaxy must have a rising rotation curve, and it cannot have a constant mass-to-light ratio. These results add to the evidence that the structures of early-type galaxies are heterogeneous.

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C. S. Kochanek, N. D. Morgan, E. E. Falco, B. A. McLeod, J. N. Winn, J. Dembicky, B. Ketzeback. 2005-08-02. The Time Delays of Gravitational Lens HE0435-1223: An Early-Type Galaxy With a Rising Rotation Curve. https://doi.org/10.1086/499766

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