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Instrument: HESSI SPECTROMETER |
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Associated Platforms RHESSI Spectral/Frequency Information Wavelength Keyword: X-Ray Number Channels: 1 Related Data Sets View all records related to this instrument Description The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) spectrometer contains nine germanium detectors that are positioned behind the nine grid pairs on the telescope. These artificially grown crystals, pure to over one part in a trillion, were manufactured by the ORTEC division of PerkinElmer Instruments. When they are cooled to cryogenic temperatures and a high voltage is put across them (up to 4000 V), they convert incoming x-rays and gamma-rays to pulses of electric current. The amount of current is proportional to the energy of the photon, and is measured by sensitive electronics designed at the Lawrence Berkeley National Laboratory and the Space Sciences Lab., Berkeley. The detectors are cooled with a recently developed electromechanical cryocooler (built by Sunpower, Inc. and flight qualified at Goddard. It maintains them at the required operating temperature of minus 324 degrees Fahrenheit (minus 198 degrees Centigrade, or 75 degrees above absolute zero). For more information, see: http://hesperia.gsfc.nasa.gov/hessi/instrumentation.htm Online Resources http://hesperia.gsfc.nasa.gov/hessi/hessispec.htm Instrument Logistics Instrument Start Date: 2002-02-05 Instrument Owner: NASA/GSFC |
