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We combine high-resolution images in four optical/infra-red bands, obtained with the laser guide star adaptive optics system on the Keck Telescope and with the Hubble Space Telescope, to study the gravitational lens system SDSSJ0737+3216 (lens redshift 0.3223, source redshift 0.5812). We show that (under favorable observing conditions) ground-based images are comparable to those obtained with HST in terms of precision in the determination of the parameters of both the lens mass distribution and the background source. We also quantify the systematic errors associated with both the incomplete knowledge of the PSF, and the uncertain process of lens galaxy light removal, and find that similar accuracy can be achieved with Keck LGSAO as with HST. We then exploit this well-calibrated combination of optical and gravitational telescopes to perform a multi-wavelength study of the source galaxy at 0.01 effective resolution. We find the Sersic index to be indicative of a disk-like object, but the measured half-light radius (0.59+-0.007+-0.1 kpc) and stellar mass (2.0+-1.0+-0.8e9Msun) place it more than three sigma away from the local disk size-mass relation. The SDSSJ0737+3216 source has the characteristics of the most compact faint blue galaxies studied, and has comparable size and mass to dwarf early-type galaxies in the local universe. With the aid of gravitational telescopes to measure individual objects brightness profiles to 10% accuracy, the study of the high-redshift size-mass relation may be extended by an order of magnitude or more beyond existing surveys at the low-mass end, thus providing a new observational test of galaxy formation models.
We discuss the optical properties of the solar gravitational lens (SGL). We estimate the power of the EM field received by an imaging telescope. Studying the behavior of the EM field at the photometric detector, we develop expressions that describe t
We investigate the optical properties of the solar gravitational lens (SGL) with respect to an extended source located at a large but finite distance from the Sun. The static, spherically symmetric gravitational field of the Sun is modeled within the
New surveys with the Spitzer space telescope identify distant star-forming and active galaxies by their strong emission at far-infrared wavelengths, which provides strong constraints on these galaxies bolometric energy. Using early results from Spitz
An attempt to measure the Hubble constant with gravitational lens time delays is often limited by the strong degeneracy between radial mass profiles of lens galaxies and the Hubble constant. We show that strong gravitational lensing of type Ia supern
It is well known that measurements of H0 from gravitational lens time delays scale as H0~1-k_E where k_E is the mean convergence at the Einstein radius R_E but that all available lens data other than the delays provide no direct constraints on k_E. T