A reassessment of the data and models of the gravitational lens Q0957+561

Abstract

We examine models of the mass distribution for the first known case of gravitational lensing. Several new sets of constraints are used, based on recent observations. We remodel the VLBI observations of the radio jets in the two images of Q0957+561, showing that the previously derived positions and uncertainties were incorrect. We use as additional constraints the candidate lensed pairs of galaxies identified recently with the Hubble Space Telescope. We explore a wider range of lens models than before, and find that the Hubble constant is not tightly constrained once elliptical lens models are considered. We also discuss the systematic uncertainties caused by the cluster containing the lens galaxy. We conclude that additional observations of the candidate lensed galaxies as well as direct measurements of the cluster mass profile are needed before an accurate value of the Hubble constant can be derived from this lens.

28 pages, Latex + 4 figures, accepted for ApJ. Final version, with minor changes. Model parameters in Table 4 corrected

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Cited by in corpus (23)

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• Observations and Theoretical Implications of the Large Separation Lensed Quasar SDSS J1004+4112
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• A determination of H_0 with the CLASS gravitational lens B1608+656: II. Mass models and the Hubble constant from lensing
• Identifying Lenses with Small-Scale Structure. II. Fold Lenses
• The Hubble constant from gravitational lens CLASS B0218+357 using the Advanced Camera for Surveys
• Improved Constraints on the Gravitational Lens Q0957+561. II. Strong Lensing
• Strong Gravitational Lensing Time Delay Statistics and the Density Profile of Dark Halos
• High resolution observations and mass modelling of the CLASS gravitational lens B1152+199
• Further Investigation of the Time Delay, Magnification Ratios, and Variability in the Gravitational Lens 0218+357
• The Detection of Pure Dark Matter Objects with Bent Multiply Imaged Radio Jets
• Constraining H0 from Chandra Observations of Q0957+561
• An analytic model for non-spherical lenses in covariant MOdified Newtonian Dynamics
• New Modeling of the Lensing Galaxy and Cluster of Q0957+561: Implications for the Global Value of the Hubble Constant
• The Dyer-Roeder distance in quintessence cosmology and the estimation of H_0 through time-delays
• Q0957+561 revised: CO emission from a disk at z=1.4
• Spectroscopy and polarimetry of the gravitationally lensed quasar Q0957+561
• Spectroscopy of the Lens Galaxy of Q0957+561A,B. Implications of a possible central massive dark object
• Finding Gravitational Lenses With X-rays
• The quasar Q0957+561: Lensed CO emission from a disk at z~1.4?
• The Central Component of Gravitational Lens Q0957+561