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The practical use of a grazing x-ray telescope is demonstrated for hard-x-ray imaging as hard as 40 keV by means of a depth-graded d-spacing multilayer, a so-called supermirror. Platinum-carbon multilayers of 26 layer pairs in three blocks with a different periodic length d of 3-5 nm were designed to enhance the reflectivity in the energy range from 24 to(More)
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 A773. 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(More)
The International Focusing Optics Collaboration for microCrab Sensitivity (InFOCmicroS) balloonborne hard x-ray telescope incorporates graded Pt/C multilayers replicated onto segmented Al foils to obtain the significant effective area at energies previously inaccessible to x-ray optics. Reflectivity measurements of individual foils demonstrate our(More)
Most of cosmic baryons predicted by the big-bang nucleosynthesis has evaded the direct detection. Recent numerical simulations indicate that approximately 30 to 50 percent of the total baryons in the present universe is supposed to take a form of warm/hot intergalactic medium (WHIM) whose X-ray continuum emission is very weak. To identify those missing(More)
Using ASCA data, we have measured the electron temperature in Abell 2163 out to 1.5 h −1 Mpc (3/4 of the virial radius, or 10a x , where a x is the X-ray core-radius) from the center, in three radial bins. The obtained temperatures are 12.2 −0.9 keV in the 0–3 a x (0–3.5 ′), 3–6 a x and 6–13 a x spherical shells, respectively 5. Formally applying the(More)
Grazing-incidence specular reflectance and near-specular scattering were measured at Al-K(alpha) (1.486-keV, 8.34-?) radiation on uncoated dielectric substrates whose surface topography had been measured with a scanning probe microscope and a mechanical profiler. Grazing-incidence specular reflectance was also measured on selected substrates at the(More)
The x-ray properties of multinested thin-foil mirror x-ray telescopes (XRT's) on board ASCA, the Advanced Satellite for Cosmology and Astrophysics, were fully evaluated with an x-ray pencil beam.Scanning over the telescope aperture of 35 cm in diameter with an x-ray pencil beam, we found the effective area of a set of XRT's to be 325, 200, and 113 cm(2) at(More)
Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several μm to more than 1000 μm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are(More)