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- The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) Imager
consists of the Imaging Telescope Assembly, which consists of the telescope
tube, grid trays, Solar Aspect System (SAS), and Roll Angle System (RAS). It
was constructed, assembled, aligned, and tested at the Paul Scherrer Institut
in Switzerland. The front and rear grid trays are attached to the telescope
tube (shown here). It maintains the separation and alignment of the trays.
Nine grids are mounted on a grid tray at each end of the telescope tube. The
grid pairs modulate the transmission of solar flare x-ray and gamma-ray
emissions through to the detectors as the spacecraft spins around the axis of
the telescope tube. The modulated count rates in the nine detectors are used in
computers on the ground to construct images of solar flares in different energy
bands.
The five coarse grids (square) were constructed by Van Beek Consultancy in The
Netherlands. The four fine grids (round) were constructed by Thermo Electron
Tecomet in Massachusetts. All grids were characterized both optically and with
X-rays at Goddard before being shipped to the Paul Sherrer Institut for
integration into the imaging telescope assembly.
For more information, see:
http://hesperia.gsfc.nasa.gov/hessi/instrumentation.htm
Group: Instrument_Details
Entry_ID: HESSI IMAGER
Group: Instrument_Identification
Instrument_Category: Solar/Space Observing Instruments
Instrument_Class: X-Ray/Gamma Ray Detectors
Short_Name: HESSI IMAGER
End_Group
Group: Associated_Platforms
Short_Name: RHESSI
End_Group
Group: Spectral_Frequency_Information
Wavelength_Keyword: X-Ray
Number_Channels: 1
End_Group
Online_Resource: http://hesperia.gsfc.nasa.gov/hessi/instrumentation.htm
Sample_Image: http://hesperia.gsfc.nasa.gov/hessi/images/Grid_Tray_Front.jpg
Group: Instrument_Logistics
Instrument_Start_Date: 2002-02-05
Instrument_Owner: NASA/GSFC
End_Group
End_Group
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