DQRID : D030203.2
Start DateStart TimeEnd DateEnd Time
01/17/2003174901/20/20031835
more
Subject:
NSA/AERI/C1 - Failure of AERI cryogenic cooler
DataStreams:nsaaerisummaryC1.a1, nsaaeriengineerC1.a1, nsaaerich1C1.a1, nsaaerich2C1.a1
Description:
In January 2003, the cryogenic cooler current for the Barrow, AERI detector was steadily 
increasing. This increase is a sign of cooler failure. On January 16,2003, the cooler 
began to make noise. The cooler was shut-off on January 17,2003 and any condensed gases were 
allowed to vent. Condensed gases in the detector dewar cause a cooler to work harder and 
increase the current. The cooler was then resealed and turned on. However, the cooler did 
not recover and the current was at a maximum. The cooler was unable to completely cool 
the detector and the detector never achieved a temperature below 72K. Higher detector 
temperature increases instrument noise. The instrument was shut off on January 20, 2003 at 
1835GMT to prevent a catatrophic failure due to complete cooler failure and 
repressurization of the detector dewar, which would result in a subsequent implosion of the dewar.
Suggestions: 
null
Data quality prior to January 17, 2003 at 1749 GMT is not affected.
Measurements:nsaaeriengineerC1.a1:
  • Shortwave HBB Noise-equivalent Radiance(SW_HBB_NEN)
  • Imaginary radiance during sky view averaged over (2510_2515 cm-1)(skyViewImaginaryRadiance2510_2515)
  • Longwave radiance average (700_705 cm^-1) elevated air(elevatedLayerRadiance700_705)
  • Longwave window brightness temperature from radiance average (985_990 cm^-1)(longwaveWindowAirTemp985_990)
  • Shortwave elevated air brightness temperature from radiance average (2282_2287
    cm-1)(elevatedLayerAirTemp2282_2287)
  • Longwave surface air brightness temperature from radiance average (675_680 cm-1)(surfaceLayerAirTemp675_680)
  • Radiance standard deviation during sky view averaged over (2282_2287 cm-1)(skyViewStdDevRadiance2282_2287)
  • Shortwave surface air brightness temperature from radiance average (2295_2300
    cm-1)(surfaceLayerAirTemp2295_2300)
  • Longwave radiance average (675-680 cm-1) Surface Air(surfaceLayerRadiance675_680)
  • ABB View Radiance Std Deviation (2282_2287 cm^-1)(ABBviewStdDevRadiance2282_2287)
  • Sky View Imaginary Radiance (675_680 cm^-1)(skyViewImaginaryRadiance675_680)
  • Shortwave window radiance average (2510_2515 cm^-1)(shortwaveWindowRadiance2510_2515)
  • Sky View Imaginary Radiance (700_705 cm^-1)(skyViewImaginaryRadiance700_705)
  • Longwave HBB noise-equivalent radiance(LW_HBB_NEN)
  • Radiance standard deviation during ambient blackbody view averaged over (985_990
    cm-1)(ABBviewStdDevRadiance985_990)
  • ABB view radiance standard deviation (2510_2515 cm^-1)(ABBviewStdDevRadiance2510_2515)
  • ABB View Radiance Std Deviation (2295_2300 cm^-1)(ABBviewStdDevRadiance2295_2300)
  • Imaginary radiance during sky view averaged over (985_990 cm-1)(skyViewImaginaryRadiance985_990)
  • Radiance standard deviation during sky view averaged over (985_990 cm^-1)(skyViewStdDevRadiance985_990)
  • Characteristic value representing overall shortwave channel responsivity(SWresponsivity)
  • Shortwave window brightness temperature from radiance average (2510_2515 cm-1)(shortwaveWindowAirTemp2510_2515)
  • Longwave elevated air brightness temperature from radiance average (700_705
    cm-1)(elevatedLayerAirTemp700_705)
  • Sky View Imaginary Radiance (2295_2300 cm^-1)(skyViewImaginaryRadiance2295_2300)
  • Shortwave radiance average (2295_2300 cm^-1) Surface Air(surfaceLayerRadiance2295_2300)
  • The noise equivalent radiance observed in the shortwave channel during a sky
    view at 2500 cm^-1(SWskyNEN)
  • The noise equivalent radiance observed in the longwave channel during a sky view
    at 1000 cm-1(LWskyNEN)
  • Shortwave radiance average (2282_2287 cm^-1) elevated air(elevatedLayerRadiance2282_2287)
  • ABB View Radiance Std Deviation (675_680 cm^-1)(ABBviewStdDevRadiance675_680)
  • ABB view radiance standard deviation (700_705 cm^-1)(ABBviewStdDevRadiance700_705)
  • Longwave window radiance average (985_990 cm^-1)(longwaveWindowRadiance985_990)
  • Radiance standard deviation during sky view averaged over (2510_2515 cm^-1)(skyViewStdDevRadiance2510_2515)
  • Radiance standard deviation during sky view averaged over (675_680 cm-1)(skyViewStdDevRadiance675_680)
  • Radiance standard deviation during sky view averaged over (700_705 cm-1)(skyViewStdDevRadiance700_705)
  • Sky view imaginary radiance (2282_2287 cm^-1)(skyViewImaginaryRadiance2282_2287)
  • Logical flag indicating whether longwave channel noise equivalent radiance is
    acceptable in sky view (true/false). Determined using LWskyNEN and
    LWskyNENlimit.(LWskyNENacceptable)
  • Characteristic value representing overall longwave channel responsivity(LWresponsivity)
  • Radiance standard deviation during sky view averaged over (2295_2300 cm^-1)(skyViewStdDevRadiance2295_2300)
more
nsaaerich1C1.a1:
  • Difference between the sky view\'s radiance variance and the hot black body
    view\'s variance(standard_dev_mean_rad)
  • Mean of radiance spectra ensemble(mean_rad)
more
nsaaerisummaryC1.a1:
  • Longwave window radiance average (985_990 cm^-1)(longwaveWindowRadiance985_990)
  • Shortwave radiance average (2282_2287 cm^-1) elevated air(elevatedLayerRadiance2282_2287)
  • Longwave radiance average (675-680 cm-1) Surface Air(surfaceLayerRadiance675_680)
  • Longwave window brightness temperature from radiance average (985_990 cm^-1)(longwaveWindowAirTemp985_990)
  • Radiance standard deviation during sky view averaged over (675_680 cm-1)(skyViewStdDevRadiance675_680)
  • Radiance standard deviation during sky view averaged over (700_705 cm-1)(skyViewStdDevRadiance700_705)
  • Radiance standard deviation during sky view averaged over (2510_2515 cm^-1)(skyViewStdDevRadiance2510_2515)
  • AERI SW scene radiance spectral averages (ch2)(SkyRadianceSpectraAveragesCh2)
  • Characteristic value representing overall longwave channel responsivity(LWresponsivity)
  • Radiance standard deviation during sky view averaged over (2282_2287 cm-1)(skyViewStdDevRadiance2282_2287)
  • Longwave radiance average (700_705 cm^-1) elevated air(elevatedLayerRadiance700_705)
  • AERI LW Scene Radiance Spectral Averages (Ch1)(SkyRadianceSpectralAveragesCh1)
  • AERI LW Scene radiance spectral averages (ch1)(SkyRadianceSpectraAveragesCh1)
  • AERI SW scene radiance spectral averages (ch2)(SkyRadianceSpectralAveragesCh2)
  • AERI SW Scene NESR Spectral Averages (Ch2)(SkyNENch2)
  • AERI SW Scene Variability Spectral Averages (Ch2)(SkyVariabilityAveragesCh2)
  • AERI LW Scene Variability Spectral Averages (Ch1)(SkyVariabilityAveragesCh1)
  • AERI LW Scene NESR Spectral Averages (Ch1)(SkyNENch1)
  • AERI LW scene brightness temp spectral averages (ch1)(SkyBrightnessTempSpectralAveragesCh1)
  • Longwave elevated air brightness temperature from radiance average (700_705
    cm-1)(elevatedLayerAirTemp700_705)
  • AERI SW scene brightness temp spectral averages (ch2)(SkyBrightnessTempSpectralAveragesCh2)
  • The noise equivalent radiance observed in the shortwave channel during a sky
    view at 2500 cm^-1(SWskyNEN)
  • AERI SW Scene Variability Spectral Averages (Ch2)(SkyUniformityCh2)
  • AERI LW Scene Variability Spectral Averages (Ch1)(SkyUniformityCh1)
  • Longwave HBB noise-equivalent radiance(LW_HBB_NEN)
  • Longwave surface air brightness temperature from radiance average (675_680 cm-1)(surfaceLayerAirTemp675_680)
  • Shortwave surface air brightness temperature from radiance average (2295_2300
    cm-1)(surfaceLayerAirTemp2295_2300)
  • Shortwave window brightness temperature from radiance average (2510_2515 cm-1)(shortwaveWindowAirTemp2510_2515)
  • AERI SW Scene NESR Spectral Averages (Ch2)(SkyNENCh2)
  • Radiance standard deviation during sky view averaged over (2295_2300 cm^-1)(skyViewStdDevRadiance2295_2300)
  • AERI LW scene NESR spectral averages (ch1)(SkyNENCh1)
  • AERI SW Scene Variability Spectral Averages (Ch2)(SkyVariabilityCh2)
  • AERI LW Scene Variability Spectral Averages (Ch1)(SkyVariabilityCh1)
  • Shortwave window radiance average (2510_2515 cm^-1)(shortwaveWindowRadiance2510_2515)
  • AERI LW Responsivity Spectral Averages (Ch1)(ResponsivitySpectraAveragesCh1)
  • AERI SW Responsivity Spectral Averages (Ch2)(ResponsivitySpectraAveragesCh2)
  • Shortwave HBB Noise-equivalent Radiance(SW_HBB_NEN)
  • Characteristic value representing overall shortwave channel responsivity(SWresponsivity)
  • AERI SW Responsivity Spectral Averages (Ch2)(ResponsivitySpectralAveragesCh2)
  • AERI LW responsivity spectral averages (ch1)(ResponsivitySpectralAveragesCh1)
  • Radiance standard deviation during sky view averaged over (985_990 cm^-1)(skyViewStdDevRadiance985_990)
  • The noise equivalent radiance observed in the longwave channel during a sky view
    at 1000 cm-1(LWskyNEN)
  • Shortwave radiance average (2295_2300 cm^-1) Surface Air(surfaceLayerRadiance2295_2300)
  • Shortwave elevated air brightness temperature from radiance average (2282_2287
    cm-1)(elevatedLayerAirTemp2282_2287)
more
nsaaerich2C1.a1:
  • Mean of radiance spectra ensemble(mean_rad)
  • Difference between the sky view\'s radiance variance and the hot black body
    view\'s variance(standard_dev_mean_rad)
more

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