Deep imaging of the double quasar QSO 0957+561: New constraints on H[SUB]0[/SUB

Abstract

view Abstract Citations (34) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Deep Imaging of the Double Quasar QSO 0957+561: New Constraints on H 0 Dahle, H. ; Maddox, S. J. ; Lilje, Per B. Abstract In this Letter we present new results from extremely deep, high- resolution images of the field around the double quasar QSO 0957+561. A possible gravitational arc system near the double quasar has recently been reported, which, if real, would set strong constraints on determinations of the Hubble constant from the time delay in the double quasar. We find that both the morphology and the colors of the claimed arc systems suggest that they are chance alignments of three and two different objects, and not gravitationally lensed arcs. Hence, the constraints on H_0_ determinations from the arcs are not valid. Also, a small group of galaxies at z = 0.5 near the line of sight, which was required to have a very large mass in the physically interesting arc models, is most likely insignificant. From our deep images we are able to use weak lensing of faint background galaxies in the field to map the gravitational potential in the main cluster. This sets new constraints on determinations of H_0_. We find that the Hubble constant is constrained to be less than 70 km s^-1^ Mpc^-1^, if the time delay between the two images of the QSO is equal to or larger than 1.1 yr. Publication: The Astrophysical Journal Pub Date: November 1994 DOI: 10.1086/187599 arXiv: arXiv:astro-ph/9408083 Bibcode: 1994ApJ...435L..79D Keywords: Astronomical Maps; Distance; Gravitational Fields; Gravitational Lenses; Hubble Constant; Imagery; Quasars; Astronomical Models; Color; Galactic Clusters; Mass Distribution; Morphology; Very Long Base Interferometry; Astronomy; COSMOLOGY: DISTANCE SCALE; COSMOLOGY: GRAVITATIONAL LENSING; Astrophysics E-Print: (uuencoded and compressed postscipt including 3 figures) full text sources arXiv | ADS | data products SIMBAD (5) NED (5)