Data Set Information
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| DATA_SET_NAME |
GALILEO PROBE NET FLUX RADIOMETER DATA V1.0
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| DATA_SET_ID |
GP-J-NFR-3-ENTRY-V1.0
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| NSSDC_DATA_SET_ID |
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| DATA_SET_TERSE_DESCRIPTION |
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| DATA_SET_DESCRIPTION |
Data Set Overview : The Galileo Probe Net Flux Radiometer (NFR) measured net and upward radiation fluxes in Jupiter's atmosphere between about 0.44 bars and 14 bars, using five spectral channels to separate solar and thermal components. The instrument used an optical head extending through the probe wall to obtain views of the Jovian atmosphere. It sampled upward and downward radiation fluxes with a single 40 degree (full angle) conical field of view chopped between directions +/- 45 degrees from horizontal. Parameters : This data set includes the Experimental Data Record (EDR) file, raw instrument counts, engineering data, corrected fluxes, calibration information, and some ancillary data (specifically time to pressure and altitude correspondence). Processing : In the engineering data, corrections were applied to thermistor sensor data. This correction was the product of analysis of discrepancies between Ambient Wall temperatures and Probe Atmospheric Structure Instrument Experiment temperatures. Details can be found in [SROMOVSKYETAL1998]. Fluxes computed from counts included corrections for detector temperature dependence, thermal perturbations, and correlated noise. Details can be found in [SROMOVSKYETAL1998]. Data : A concise description of each file in the archive follows, segregated by subdirectory. nfr/calib: nfrfovX.lbl -- header labels for field-of-view data for channel X, where X is channel name, A-F nfrfovX.dat -- data files for field-of-view data for channel X tdepresp.tab -- temperature dependent absolute responsivity data tdsrX.tab -- temperature dependent spectral response for channel X nfr/edr: nfr0528x.sdm -- final merged Experimental Data Record (EDR) file nfr/engnring: nfra1.tab -- ambient wall temperature, high range nfra1vv.tab -- ambient wall temp., high range, corrected drive voltage nfra2.tab -- ambient wall temp., low range nfra2vv.tab -- ambient wall temp., low range, corrected drive voltage nfrbi.tab -- hot blackbody heater current nfrdt.tab -- detector temp. nfret.tab -- electronics module temp. nfrhb.tab -- hot blackbody temp. nfrhbvv.tab -- hot blackbody temp., corrected drive voltage nfrv1.tab -- A/D converter reference voltage (+10V, V1) nfrv2.tab -- preamp module voltage (+7V, V2) nfrwi.tab -- diamond window heater current nfrwt.tab -- diamond window temp. nfrwtvv.tab -- diamond window temp., corrected drive voltage nfr/fluxes: mctcnf.tab -- m-corrected, temperature-corrected net fluxes mctcnfdn.tab -- m-corr., temp-corr. net fluxes, correlated noise removed mctcuf.tab -- m-corr., temp-corr up fluxes rawnf.tab -- uncorrected net fluxes rawnfdn.tab -- uncorrected net fluxes, correlated noise removed rawuf.tab -- uncorrected up fluxes tcnf.tab -- temp-corrected net fluxes tcnfdn.tab -- temp-corrected net fluxes, correlated noise removed tcuf.tab -- temp-corrected up fluxes nfr/fluxes/calib: bbamb.tab -- computed flux from ambient wall blackbody bbhot.tab -- computed flux from hot blackbody bcflux.tab -- computed Blackbody Cal mode flux (bbhot - bbamb) nfr/raw: nfraz.tab -- Analog Zero (AZ) mode counts, short-cycled nfrbc.tab -- Blackbody Cal (BC) mode counts nfrerr.tab -- position error bit counts nfrgsa.tab -- Gain Select Amplitude (GSA) counts nfrnf.tab -- Net Flux (NF) mode counts, non-short-cycled data nfrrXX.tab -- raw counts for engineering data in nfr/engnring nfrsc.tab -- Net Flux (NF) mode counts, short-cycled data nfruf.tab -- Up Flux (UF) mode counts nfr/raw/denoised: nfrnfdn.tab -- NF mode counts, non-short-cycled, correlated noise removed nfrscdn.tab -- NF mode counts, short-cycled, correlated noise removed nfr/catalog: nfrinst.cat -- instrument description file referenc.cat -- document reference file dataset.cat -- this file software: nfredr41.c -- C program for reading EDR file nfredr4.h -- include file for nfredr41.c read_flux.pro -- example IDL program for reading flux file and interpolating pressure from ASI data readfile.pro -- IDL file reading function called by read_flux.pro Data Reduction Example : The following example is to aid in applying the slowly varying offset correction to the temperature-corrected, correlated-noise-removed net fluxes in /data/nfr/fluxes/tcnfdn.tab. Slowly Varying Offset Correction Equation 15 in [SROMOVSKYETAL1998]. F_nc : F_nr - m_n*C_F*(G_n/G_F)*(R_F_Tr/(R_F_T*R_n_Tr)) Where: F_nc Net flux in channel n [A,B,C,D,E,F] m-corrected, temp-corrected net fluxes, correlated-noise-removed. (W/m^2) Corrected fluxes in /data/nfr/fluxes/mctcnfdn.tab F_nr Net flux in channel n [A,B,C,D,E,F] temperature-corrected net fluxes, correlated-noise-removed. (W/m^2) Fluxes in /data/nfr/fluxes/tcnfdn.tab m_n Multiplier factor, m-factor. Adapted values for channels [A,B,C,D,E,F], uncertainties are (xx) [SROMOVSKYETAL1998] Table 2): [1.05 (0.15),0.70 (0.1),3.90 (0.2),2.10 (0.05),1.35 (0.05), 1.00] C_F Channel F temperature-corrected net flux counts, correlated-noise-removed. Counts in /data/nfr/raw/denoised/nfrnfdn.tab or nfrscdn.tab NOTE: These counts should be smoothed. [SROMOVSKYETAL1998] used a sliding quadratic fit over 19 successive points. G_n,G_F Gain for channel n and F respectively. G_n : [127,218,408,321,403,127] ([SROMOVSKYETAL1998] Table 2) G_F : 127 R_F_Tr Responsivity of channel F at the reference temperature of 25 degrees C. R_F_Tr : [255.7,771.9,1399.6,953.0,1364.9,255.7] Responsivity in /data/nfr/calib/tdepresp.tab. R_F_T Responsivity of channel F at the respective detector temperature of TD_temp. Responsivity in /data/nfr/calib/tdepresp.tab. Detector temperature in /data/nfr/engnring/nfrdt.tab R_n_Tr Responsivity of channel n at the reference temperature of 25 degrees C. Responsivity in /data/nfr/calib/tdepresp.tab. For the pressure nearest the 5 bar level, time : 1161.75, Major frame : 9, minor frame : 12, time : 1158.75, TD_temp : -17.79 F_nr : [3.573,0.029,5.191,2.380,1.037,1.331] m_n : [1.05,0.70,3.90,2.10,1.35,1.00] C_F : 324.3 (uncorrected : 318, average of 5 : 320.78) G_n : [127,218,408,321,403,127] R_n_Tr : [255.7,771.9,1399.6,953.0,1364.9,255.7] R_F_t : 239.0 Inserting the values above into Equation 15 of [SROMOVSKYETAL1998] F_nc : F_nr - m_n*C_F*(G_n/G_F)*(R_F_Tr(5)/(R_F_T*R_n_Tr)) Gives the corrected flux values: 2.148 -0.511 2.085 0.448 -0.052 -0.026 Corresponding values from /data/nfr/fluxes/mctcnfdn.tab: 2.148 -0.511 2.084 0.447 -0.056 0.000 Ancillary Data : This includes data from the ASI team which contains correspondence between time, altitude, and pressure. This file is based on ASI data received 28 May 1997; please retrieve the most recent data from the ASI experiment archive. Coordinate System : The NFR data files include time (specifically time after Minor Frame Zero), which can be used to compare results to those of other Probe instruments, and to associate altitude and pressure information to the NFR data points (using the ancillary information described above). Software : Software include in the data set includes: nfredr41.c: Software for decoding the NFR EDR file and writing files of instrument counts.
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| DATA_SET_RELEASE_DATE |
1996-12-08T00:00:00.000Z
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| START_TIME |
1995-12-07T09:05:44.000Z
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| STOP_TIME |
1995-12-07T11:35:44.000Z
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| MISSION_NAME |
GALILEO
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| MISSION_START_DATE |
1977-10-01T12:00:00.000Z
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| MISSION_STOP_DATE |
2003-09-21T12:00:00.000Z
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| TARGET_NAME |
JUPITER
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| TARGET_TYPE |
PLANET
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| INSTRUMENT_HOST_ID |
GP
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| INSTRUMENT_NAME |
NET FLUX RADIOMETER
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| INSTRUMENT_ID |
NFR
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| INSTRUMENT_TYPE |
RADIOMETER
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| NODE_NAME |
Planetary Atmospheres
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| ARCHIVE_STATUS |
ARCHIVED
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| CONFIDENCE_LEVEL_NOTE |
Confidence Level Overview : The same algorithms used in producing the processed data files were used in generating data for the final instrument paper, [SROMOVSKYETAL1998]. There is a slight error in channel C up flux in [SROMOVSKYETAL1998]. Fig. 25. The correct values are in /data/nfr/fluxes/mctcuf.tab. Review : This data set has been used internally by the NFR team in production of the final instrument paper, [SROMOVSKYETAL1998]. The data set will be independently reviewed by PDS. Data Coverage and Quality : Flux data acquired below the 14-bar level (Data Cycle 21, 2500 seconds after Minor Frame Zero), are considered to be invalid, due to reduced detector responsivity at high temperature. For a full discussion of data confidence level, see [SROMOVSKYETAL1998]. There is a slight error in channel C up flux in [SROMOVSKYETAL1998]. Fig. 25. The correct values are in /data/nfr/fluxes/mctcuf.tab. Limitations : Ancillary data from the Atmospheric Structure Instrument (ASI) is required to correlate NFR sample times with altitude and pressure.
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| CITATION_DESCRIPTION |
Citation TBD
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| ABSTRACT_TEXT |
The Galileo Probe Net Flux Radiometer (NFR) measured net and upward radiation fluxes in Jupiter's atmosphere between about 0.44 bars and 14 bars, using five spectral channels to separate solar and thermal components. The instrument used an optical head extending through the probe wall to obtain views of the Jovian atmosphere. It sampled upward and downward radiation fluxes with a single 40 degree (full angle) conical field of view chopped between directions +/- 45 degrees from horizontal.
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| PRODUCER_FULL_NAME |
LAURENCE SROMOVSKY
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| SEARCH/ACCESS DATA |
Atmospheres Online Archives
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