PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 1998-05-01 NOTE = "DATASET.TXT contains the data set description." END_OBJECT = TEXT END Data Set Summary ================ Data Set ID: VG1-J-PWS-4-SUMM-SA-48.0SEC-V1.1 Instrument: PWS Instrument P.I.: Donald A. Gurnett Data Supplier: William S. Kurth Data sampling rate: 48 seconds Data Set Start time: 1979-02-28T00:00:00.000Z Data Set Stop time: 1979-03-22T23:59:12.000Z Record format ------------- These files can be read according to the FORTRAN format statement: '(a24,16(1x,1pe9.2),1x,i2)' where 'a24' is the time stamp in PDS format: yyyy-mm-ddThh:mm:ss.sssZ. The individual elements of the time field can be read according to the statement: '(i4,4(1x,i2),1x,f6.3,1x)' year, month, day, hour, minute, seconds. Thus a record may alternatively be read according to the format: '(i4,4(1x,i2),1x,f6.3,1x,16(1x,1pe9.2),1x,i2)' Data column descriptions ------------------------ time a24 time in the format yyyy-mm-ddThh:mm:ss.sssZ data channel -- 16 1pe9.2 format 48 second averaged wave electric field values for each of the PWS data channels (volts/meter). Channels 01-16 have center frequencies ranging from 10 Hz to 56.2 kHz, logarithmically spaced in frequency, four channels per decade. The center frequencies and bandwidths of each PWS spectrum analyzer channel for each Voyager spacecraft are given below: VOYAGER 1 PWS SPECTRUM ANALYZER Voyager-1 Channel Center Frequency Bandwidth 1 10.0 Hz 2.99 Hz 2 17.8 Hz 3.77 Hz 3 31.1 Hz 7.50 Hz 4 56.2 Hz 10.06 Hz 5 100. Hz 13.3 Hz 6 178. Hz 29.8 Hz 7 311. Hz 59.5 Hz 8 562. Hz 106. Hz 9 1.00 kHz 133. Hz 10 1.78 kHz 211. Hz 11 3.11 kHz 298. Hz 12 5.62 kHz 421. Hz 13 10.0 kHz 943. Hz 14 17.8 kHz 2110 Hz 15 31.1 kHz 4210 Hz 16 56.2 kHz 5950 Hz wvfrmavl i2 waveform flag (1 = wideband waveform data available) Missing data flag value ----------------------- Any columns containing the value -9.99e+10 or -9 (depending upon column format) is a missing data value. Data Description ================ Instrument P.I. : Donald A. Gurnett Data Supplier : William S. Kurth Data sampling rate : 48 seconds Data Set Start Time : 1979-02-28T00:00:00.000Z Data Set Stop Time : 1979-03-22T23:59:12.000Z Version 1.1 ----------- This version 1.1 data set replaces the version 1.0 data set (DATA_SET_ID = VG1-J-PWS-4-SA-48.0SEC) previously archived with the PDS. Changes to this version include upgrading of the associated labels and templates to PDS version 3.2 compliance and modification of the time formats and flag values. Data Set Description -------------------- This data set consists of 48-second calibrated, averaged wave electric field intensities from the Voyager 1 Plasma Wave Receiver spectrum analyzer obtained in the vicinity of the Jovian magnetosphere. For each 48-second interval, a geometric average field strength is determined for each of the 16 spectrum analyzer channels whose center frequencies range from 10 Hertz to 56.2 kiloHertz and which are logarithmically spaced in frequency, four channels per decade. Averages are stored in units of volt/meter. During data gaps where complete 48-second intervals are missing, no entries exist in the file, that is, the gaps are not zero-filled or tagged in any other way. Additional information about this data set and the instrument which produced it can be found elsewhere in this catalog. An overview of the data in this data set can be found in [SCARFETAL1979] and a complete instrument description can be found in [SCARF&GURNETT1977]. Processing Level Id : 4 Software Flag : Y Processing Start Time : 1988-02-01 Parameters ---------- Sampling Parameter Name : TIME Data Set Parameter Name : PLASMA WAVE SPECTRUM Sampling Parameter Resolution : 48.000000 Minimum Sampling Parameter : 197709051420.000000 Sampling Parameter Interval : 48.000000 Minimum Available Sampling Int : 4.000000 Data Set Parameter Unit : VOLT/METER Noise Level : 0.000005 Sampling Parameter Unit : SECOND A set of derived parameters consisting of wave electric field intensities or electric field spectral densities at various contiguous frequencies over a range of frequencies. The MKS units are: Volts/Meter or Volts**2/(Hertz Meter**2), respectively. Source Instrument Parameters ---------------------------- Instrument Host ID : VG1 Data Set Parameter Name : PLASMA WAVE SPECTRUM Instrument Parameter Names : ELECTRIC FIELD WAVEFORM ELECTRIC FIELD COMPONENT MAGNETIC FIELD COMPONENT WAVE ELECTRIC FIELD INTENSITY WAVE MAGNETIC FIELD INTENSITY Important Instrument Parameters : 1 (for all parameters) Processing ---------- Processing History ------------------ Source Data Set ID : N/A Software : UNK Product Data Set ID : VG1-J-PWS-4-SA-48.0SEC Source Data Set ID : VG1-J-PWS-2-SA-4.0SEC Software : V1J48 Product Data Set ID : VG1-J-PWS-4-SA-48.0SEC Software 'V1J48' ---------------- Software Name : V1J48 Software Type : N/A Software Release Date : 1988-08-01 Node ID : PPI-IOWA Cognizant Engineer : LARRY J. GRANROTH Software Access Description : NOT ACCESSIBLE THROUGH PDS CATALOG - CONTACT NODE V1J48 is a specialized, hard-coded routine to process a specific interval of Voyager 1 PWS spectrum analyzer data around Jupiter encounter. Input is from MSF or CD data sets produced and stored at the University of Iowa, and output is to ASCII text files which are compatible with PDS data loading procedures. These files contain information corresponding to the VG1-J-PWS-4-SA-48.0SEC data set. Confidence Level Overview ------------------------- This data set includes all available spectrum analyzer data within the interval of time covered. The data set has been cleaned as well as possible for periodic noise spikes due to a stepper motor operating on the LECP and a modulated grid within the PLS. The averages do not include these noise spikes. Other possible sources of noise which have not been eliminated include random intense spikes of noise below 1 kiloHertz due to the operation of attitude control thrusters. Other randomly occurring spikes or time periods of intense spikes over the entire frequency range are indicative of telemetry errors. No attempt has been made to remove spikes since some could be valid data, i.e. real bursts of wave activity. The 17.8-Hz channel is sometimes contaminated by interference from the PRA instrument, depending on that instrument's mode. This interference is at a relatively constant level.