Open AccessH 0 from an orientation‐unbiased sample of Sunyaev–Zel'dovich and X‐ray clusters
Author(s) -
Jones Michael E.,
Edge Alastair C.,
Grainge Keith,
Grainger William F.,
Kneissl Rüdiger,
Pooley G. G.,
Saunders Richard,
Miyoshi Shigeru J.,
Tsuruta Taisuke,
Yamashita Koujun,
Tawara Yuzuru,
Furuzawa Akihiro,
Harada Akihiro,
Hatsukade Isamu
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.08626.x
Subject(s) - rosat , physics , astrophysics , galaxy cluster , redshift , cluster (spacecraft) , surface brightness , sunyaev–zel'dovich effect , substructure , quasar , hubble's law , galaxy , structural engineering , computer science , engineering , programming language
We have observed the Sunyaev–Zel'dovich (SZ) effect in a sample of five moderate‐redshift clusters with the Ryle Telescope, and used them in conjunction with X‐ray imaging and spectral data from ROSAT and ASCA to measure the Hubble constant. This sample was chosen with a strict X‐ray flux limit using both the Bright Cluster Sample and the Northern ROSAT All‐Sky Survey (RASS) cluster catalogues to be well above the surface brightness limit of the RASS, and hence to be unbiased with respect to the orientation of the cluster. This controls a major potential systematic effect in the SZ/X‐ray method of measuring H 0 . Taking the weighted geometric mean of the results and including the main sources of error, namely the noise in the SZ measurement, the uncertainty in the X‐ray temperatures and the unknown ellipticity and substructure of the clusters, we find H 0 = 59 +10 −9 (random) +8 −7 (systematic) km s −1 Mpc −1 assuming a standard cold dark matter model with Ω M = 1.0, Ω Λ = 0.0 or H 0 = 66 +11 −10 +9 −8 km s −1 Mpc −1 if Ω M = 0.3, Ω Λ = 0.7 .