A measurement of H_0 from Ryle Telescope, ASCA and ROSAT observations of Abell 773

Richard Saunders; Ruediger Kneissl; Keith Grainge; William F. Grainger; Michael E. Jones; Alessia Maggi; Rhiju Das; Alastair Edge; A. N. Lasenby; G. G. Pooley; Shigeru J. Miyoshi; Taisuke Tsuruta; Koujun Yamashita; Yuzuru Tawara; Akihiro Furuzawa; Akihiro Harada; Izamu Hatsukade

doi:10.1046/j.1365-8711.2003.06467.x

arXiv · astro-ph/9904168

A measurement of H_0 from Ryle Telescope, ASCA and ROSAT observations of Abell 773

Richard Saunders·Ruediger Kneissl·Keith Grainge·William F. Grainger·Michael E. Jones·Alessia Maggi·Rhiju Das·Alastair Edge·A. N. Lasenby·G. G. Pooley·Shigeru J. Miyoshi·Taisuke Tsuruta·Koujun Yamashita·Yuzuru Tawara·Akihiro Furuzawa·Akihiro Harada·Izamu Hatsukade

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Abstract

We present new Ryle Telescope (RT) observations of the Sunyaev Zel'dovich (SZ) decrement from the cluster Abell 773. The field contains a number of faint radio sources that required careful subtraction. We use ASCA observations to measure the gas temperature and a ROSAT HRI image to model the gas distribution. Normalising the gas distribution to fit the RT visibilities returns a value of H_0 of 77 (+19,-15) km/s/Mpc (1-sigma errors) for an Einstein-de-Sitter universe, or 85 (+20,-17) km/s/Mpc for a flat model with Omega_Lambda = 0.7. The errors quoted include estimates of the effects of the principal errors: noise in the SZ measurement, gas temperature uncertainty, and line-of sight depth uncertainty.

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Richard Saunders, Ruediger Kneissl, Keith Grainge, William F. Grainger, Michael E. Jones, Alessia Maggi, Rhiju Das, Alastair Edge, A. N. Lasenby, G. G. Pooley, Shigeru J. Miyoshi, Taisuke Tsuruta, Koujun Yamashita, Yuzuru Tawara, Akihiro Furuzawa, Akihiro Harada, Izamu Hatsukade. 2003-03-10. A measurement of H_0 from Ryle Telescope, ASCA and ROSAT observations of Abell 773. https://doi.org/10.1046/j.1365-8711.2003.06467.x

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