Zobrazeno 1 - 10
of 76
pro vyhledávání: '"D.J. Bassford"'
Autor:
N. Babazadeh, Chee Hing Tan, A.M. Barnett, R.B. Gomes, D.J. Bassford, Jo Shien Ng, John E. Lees
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 654:336-339
Circular mesa GaAs p+–i–n+ diodes for photon counting soft X-ray spectroscopy have been fabricated and characterised over a temperature range of +80 to –30 °C. The spectroscopic performance of the diodes, as measured by the FWHM of the Mn Kα
Autor:
Chee Hing Tan, Jo Shien Ng, John E. Lees, A.M. Barnett, John P. R. David, D.J. Bassford, R.B. Gomes
Publikováno v:
IEEE Transactions on Electron Devices. 58:1696-1701
Realistic Monte Carlo simulations for the avalanche gain of absorbed X-ray photons were carried out in a study of the relationship between avalanche gain and energy resolution for semiconductor X-ray avalanche photodiodes (APDs). The work explored ho
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. :25-30
First results from a new simple simulation of X-ray spectroscopy with an Al0.8Ga0.2As p+–p−–n+ spectroscopic X-ray photon counting avalanche photodiode are presented and compared with experimentally obtained data. Particular attention is paid t
Publikováno v:
Applied Radiation and Isotopes. 68:2448-2451
There is now wide spread interest in the application of small field of view gamma cameras for clinical use in operating theatres, intensive care units and bedside imaging. The development of these imaging systems some of which have improved spatial r
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 594:202-205
Al0.8Ga0.2As p+–p−–n+ diodes with low reverse leakage currents ( 20 V), we observed avalanche multiplication which, while improving the signal-to-noise ratio, degraded the spectroscopic performance.
Autor:
G.W. Fraser, John E. Lees, Konstantin Vassilevski, Nicholas G. Wright, Alton B. Horsfall, Alan Owens, D.J. Bassford
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 578:226-234
We describe a novel SiC Schottky diode architecture. The semi-transparent SiC Schottky diode has an “ultra-thin” (18 nm Ni/Ti) Schottky contact, a gold annular overlayer and a gold corner-contact pad. We show that the new architecture exhibits th
Autor:
I. Moody, John E. Lees, D. Monk, R. J. Ott, Alan C. Perkins, M. Early, D.J. Bassford, G.W. Fraser, Elaine Blackshaw
Publikováno v:
Scopus-Elsevier
We describe the development of a scintillator-coated charge coupled device (CCD) based camera for imaging small volumes of radionuclide uptake in tissues. The high resolution gamma imager (HRGI) is a collimated, scintillator-coated, low cost, high pe
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 537:621-625
We describe novel electronics for processing signals from a microchannel plate detector using a resistive anode readout. High sampling-rate (MHz) Analogue-to-Digital Converters (ADCs) coupled to a Digital Signal Processor (DSP) combine to offer high
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 629:154-156
The temperature dependence of the avalanche multiplication process at soft X-ray energies in Al 0.8 Ga 0.2 As avalanche photodiodes (APDs) is investigated at temperatures from +80 to −20 °C. The temperature dependence of the pure electron initiate
Publikováno v:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 621:453-455
We have fabricated and characterised unpassivated 200 μm diameter circular mesa Al0.8Ga0.2As p+–i–n+ diodes as soft X-ray photon counting detectors. The spectroscopic performance, as measured by the FWHM of the 5.9 keV X-ray line from an 55Fe ra