William F. Grainger

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We have observed the Sunyaev–Zel’dovich 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 BCS and NORAS cluster catalogues to be well above the(More)
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 density distribution. Normalizing the gas distribution to fit(More)
We describe a maximum-likelihood technique for the removal of contaminating radio sources from interferometric observations of the Sunyaev–Zel’dovich (SZ) effect. This technique, based on a simultaneous fit for the radio sources and extended SZ emission, is also compared to techniques previously applied to Ryle Telescope observations and is found to be(More)
A laboratory prototype spectral-spatial interferometer has been constructed to demonstrate the feasibility of the double-Fourier technique at far infrared (FIR) wavelengths (0.15-1 THz). It is planned to use this demonstrator to investigate and validate important design features and data-processing methods for future astronomical FIR interferometer(More)
We investigate the possibility of using a flat-fold beam steering mirror for a cosmic microwave background B-mode experiment. An aluminium flat-fold mirror is found to add ∼0.075% polarization, which varies in a scan synchronous way. Time-domain simulations of a realistic scanning pattern are performed, and the effect on the power-spectrum illustrated, and(More)
SCUBA-2 is a state of the art 10,000 pixel submillimeter camera installed and being commissioned at the James Clerk Maxwell Telescope (JCMT) providing wide-field simultaneous imaging at wavelengths of 450 and 850 microns. At each wavelength there are four 32 by 40 sub-arrays of superconducting Transition Edge Sensor (TES) bolometers, each packaged with(More)
We present the results of radio, optical and near-infrared observations of the field of TOC J0233.3+3021, a cluster of milliJansky radiosources from the TexOx Cluster survey. In an observation of this field with the Ryle Telescope (RT) at 15 GHz, we measure a decrement in the cosmic microwave background (CMB) of−675±95μJy on the RT’s ≈ 0.65 kλ baseline.(More)
We present the results of radio, optical and near-infrared observations of the field of TOC J0233.3þ3021, a cluster of milliJansky radio sources from the TexOx Cluster survey. In an observation of this field with the Ryle Telescope (RT) at 15 GHz, we measure a decrement in the cosmic microwave background (CMB) of 2675 ^ 95mJy on the RT’s < 0:65 kl baseline.(More)
We have developed a passive 350 GHz (850 μm) video-camera to demonstrate lumped element kinetic inductance detectors (LEKIDs)--designed originally for far-infrared astronomy--as an option for general purpose terrestrial terahertz imaging applications. The camera currently operates at a quasi-video frame rate of 2 Hz with a noise equivalent temperature(More)
We have mapped the high-redshift (z = 0.546) cluster Cl 0016+16 with the Ryle Telescope at 15 GHz. The Sunyaev–Zel’dovich decrement is clearly detected, and resolved. We combine our data with an X-ray image from ROSAT, and a gas temperature from ASCA to estimate the Hubble Constant H0 = 69+21 −16 km s −1 Mpc−1 for an ΩM = 1.0 cosmology or H0 = 84+25 −19 km(More)