CDS
type: Concept
definition: The Coronal Diagnostics Spectrometer (CDS) experiment on the Solar Heliospheric Observatory (SOHO) spacecraft is designed to determine such information through the study of emission line characteristics in the extreme ultraviolet (EUV) - particularly essential for the detection of emission from the hottest plasmas in the (non-flare) solar atmosphere. This is complementary to the remaining coronal instrument package on SOHO which includes a longer-wavelength UV spectrometer, an EUV imager and two coronagraphs (UV and white light). The CDS consists of a Wolter II grazing incidence telescope which has a focus at a slit assembly which lies beyond a scan mirror. Light stops define two telescope apertures which feed, simultaneously into two spectrometers beyond the slit assembly. One portion of the beam hits a grating in grazing incidence and the spectrum is dispersed onto four 1-D detectors placed around the Rowland circle. This is the grazing incidence spectrometer or GIS. The other portion is fed through to a twin grating in normal incidence and the resulting spectrum is viewed by a 2-D detector system. This is the normal incidence spectrometer or NIS. For more information, see: http://solar.bnsc.rl.ac.uk/ Group: Instrument_Details Entry_ID: CDS Group: Instrument_Identification Instrument_Category: Solar/Space Observing Instruments Instrument_Class: Ultraviolet Instruments Short_Name: CDS Long_Name: Coronal Diagnostics Spectrometer End_Group Group: Associated_Platforms Short_Name: SOHO End_Group Group: Spectral_Frequency_Information Wavelength_Keyword: Ultraviolet Number_Channels: 2 Spectral_Frequency_Coverage_Range: 15.0-80.0 nm Spectral_Frequency_Resolution: 2 arcsec End_Group Online_Resource: http://solar.bnsc.rl.ac.uk/ Group: Instrument_Logistics Instrument_Start_Date: 1995-12-02 Instrument_Owner: Rutherford Appleton Labs End_Group End_Group
in scheme: instruments

Ultraviolet Instruments
type: Concept