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Constraints on H0 from the central velocity dispersions of lens galaxies
Astrophysical Journal (1999)
  • Aaron J. Romanowsky, San Jose State University
  • C. S. Kochanek

We employ Schwarzschild's method of the orbit modeling to constrain the mass profiles of the central lens galaxies in Q0957+561 and PG 1115+080. We combine the measured, central projected stellar velocity dispersions of these galaxies with the self-similar radial profiles of the rms velocity and of the Gauss-Hermite moment h4 observed in nearby galaxies for 0 lesssim R lesssim 2Reff. For Q0957+561, we find a 16% uncertainty in the galaxy mass and formal 2 σ limits on the Hubble constant of H0=61$\mathstrut{^{+13}_{-15}}$ km s-1 Mpc-1. For PG 1115+080, we find that none of the viable lens models can be ruled out, so that H0 is not yet strongly constrained by this system.

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Copyright © 1999 American Astronomical Society. The published article may be found at :
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Aaron J. Romanowsky and C. S. Kochanek. "Constraints on H0 from the central velocity dispersions of lens galaxies" Astrophysical Journal Vol. 516 (1999)
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