@prefix ns0: <http://gcmd.gsfc.nasa.gov/kms#> .
@prefix skos: <http://www.w3.org/2004/02/skos/core#> .

<https://gcmd.earthdata.nasa.gov/kms/concept/a9c0abe0-204e-414a-89ba-dae7da179cbe>
  ns0:resource [ ] ;
  skos:definition """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"""@en ;
  skos:prefLabel "HESSI IMAGER"@en ;
  skos:inScheme <https://gcmd.earthdata.nasa.gov/kms/concepts/concept_scheme/instruments> ;
  skos:broader <https://gcmd.earthdata.nasa.gov/kms/concept/d49b2313-2fb1-464c-a2f8-5ff5799344a7> ;
  a skos:Concept .

<https://gcmd.earthdata.nasa.gov/kms/concept/d49b2313-2fb1-464c-a2f8-5ff5799344a7>
  skos:prefLabel "X-Ray/Gamma Ray Detectors"@en ;
  a skos:Concept ;
  skos:narrower <https://gcmd.earthdata.nasa.gov/kms/concept/a9c0abe0-204e-414a-89ba-dae7da179cbe> .