NEW RESULTS WITH SILICON PAD DETECTORS AND LOW-NOISE ELECTRONICS FOR ABSORPTION SPECTROMETRY

High-resistivity silicon diode detectors integrable in array structure s have been tested for high-resolution X-ray spectroscopy at various t emperatures. Using an inexpensive commercially available front-end tra nsistor we have obtained resolutions of 19 electrons rms, or 165 eV FW HM, at -35 degrees C and 39 electrons rms, or 320 eV FWHM, at 26 degre es C, with 3 and 1 mu s shaping times. The obtained resolution values are adequate for synchrotron light based EXAFS experiments. These reli able detectors can be suitably employed for high-performance multichan nel systems in which high-rate capability is achieved by using an arra y of detectors operated in parallel. A 16-element detector prototype h as been recently assembled, installed and successfully operated for a real EXAFS experiment at NSLS.