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NASA Space Science Data Coordinated Archive Header



Availability: Archived at NSSDC, accessible from elsewhere

Time span: 1989-10-21 to 1989-10-28


This description was generated automatically using input from the Planetary Data System.

This data set includes values for the fluxes of heavy ions associated with an energetic particle event of solar origin. Dataset Structure / Content: The data files are ASCII tables of values. Included in the label file (*.LBL) is a header for each data table. The header gives the data processing time, requested time intervals, the actual time interval and livetime paramaters. Note that while the data files have widths of more than 80 characters, the example data shown below has been wrapped in order to conform to a 80 character line limitation. Header Example: Galileo HIC Mon Sep 18 10:01:58 1995 Requested Interval: 28237 28384 1989/294.12 - 1989/295.67 Actual Interval: 28237 28384 1989/294.12 - 1989/295.67 LET B Livetime Parameters doubles triples Rate Counts : 136768 137168 Times : 131488 132110 PHA Counts : 43369 43369 Livetimes : 4.17e+04 4.18e+04 LET E Livetime Parameters TRPL WS.L1* WS.L1 Rate Counts : 6345 14180 14180 Times : 132102 132102 132102 PHA Counts : 3414 7398 7398 Livetimes : 7.11e+04 6.89e+04 6.89e+04 Element Oxygen Oxygen LET B B Energy 5.40 7.25 Width 0.40 0.75 doubles 2252 -1 triples -1 2385 WS.L1* -999 -999 WS.L1 -999 -999 Total 2252 2385 Flux 1.53e-01 8.65e-02 Lower 3.23e-03 1.77e-03 Upper 3.30e-03 1.81e-03 Avg-Lt 4.17e+04 4.18e+04 Geom-Fac 4.40e-01 4.40e-01 End Example. Header Description: The first line of the header gives the Spacecraft, Instrument and Data processing time. The second line of the of the header gives the data processing input as 4 columns. The first two columns are start/stop volumes where a volume is number of 15 minute intervals from the start of 1989. The last two columns are the start/stop time given in Spacecraft Event Time (UTC) computed from the start/stop volumes. Volumes times are provided in year and fractional day-of-year (DOY) format for the center time of the interval. In other words, you can compute the fractional DOY by the formula: DOY = [(VOLUME * 15) - 7.5] / (24 * 60) The third line of the header contains the actual values for the same start stop columns as the requested interval. The actual interval may be shorter than the resuested interval if data are not available for the entire requested interval. Line 4 is blank and lines 5-17 give livetime parameters which are described in further detail below. Line 18 is blank, line 19 is column headings, and line 20 is a line of underscores. Livetime parameters are summarized as follows: Rate Counts - holds the total number of ions which triggered that detector/buffer combination Times - refers to number of seconds during which the buffer was active PHA Counts - is the number of ion event descriptions telemetered via that buffer, and Livetimes - are calculated from that info. Note that fractional livetime changes substantially during the flare interval, so that averaging is required. The absolute flux values are subject to an additional systematic uncertainty depending on the relevance of the averaging technique to the use of the flux values. Data Table description: Column 1: Element - The name of the ion being described. Column 2: LET - The identifier of the LET telescope, examples show telescopes B and E. Column 3: Energy - The energy center for the telescope during its energy scan <MeV/nucleon> Column 4: Bandwidth - The width of the energy band around the Column 5: Doubles - The number of ions stopping in detector LB2 in the given MeV/nucleon energy range Column 6: Triples - For LET-B, the number of ions stopping in L3 in the given MeV/nucleon energy range. For LET-E, the number of events triggering L1 L2 L3 L4* L5* where * indicates a detector that was not-triggered. Column 7: WS.L1* - a wide-stop (L1* L2 L3 L4 L5*) event which did not hit L1. Column 8: WS.L1 - a wide-stop (L1 L2 L3 L4 L5*) event which did hit L1. Column 9: Total - Total number of events (sum of doubles and triples). Column 10: Flux - The calculated flux in units of particles/cm^2-sr-sec-(MeV/Nuc). Column 11: Lower - Statistical uncertainties in the flux value, giving the lower limit of the 68% confidence interval. Column 12: Upper - Statistical uncertainties in the flux value, giving the upper limit of the 68% confidence interval. Column 13: Avg-LT - Average livetime of the detector/buffer combination Column 14: Geom-Fac - Geometric factor /* Need more info here */ Note: -1 indicates that a measurement was not made and 0 indicates that no counts were detected, -999 means the column is not applicable for this detector. For LET B, the number of ions stopping in detector LB2 in the given MeV/nucleon Energy-range is listed in the Doubles column, and the ions stopping in LB3 are listed under Triples; the Total column sums the double and triple coincidence events. The calculated value for flux is given in the Flux column. Flux is given in units of particles/cm^2-sr-sec-(MeV/Nuc). Lower and Upper refer to the statistical uncertainties in flux values, giving the upper and lower limits of the 68% confidence interval. Avg-LT is the average live time of the detector/buffer combination, in seconds. For telescope LET E, the columns and refer to the same parameters as those previously mentioned for LET B, with the exceptions of columns triple, WS.L1*, and WS.L1. These headings refer to the different event types in this telescope: triple refers to an event triggering L1 L2 L3 L4* L5*, where an asterisk denotes a miss; WS.L1* categorizes a wide-stop (L2 L3 L4 L5*) event which did not hit L1; and WS.L1 indicates the wide-stop events which do trigger detector L1 (L1 L2 L3 L4* L5*).

These data are available on-line from the Planetary Data System (PDS) at:

Alternate Names



  • Planetary Science: Fields and Particles

Additional Information



Questions and comments about this data collection can be directed to: Dr. Edwin V. Bell, II



NameRoleOriginal AffiliationE-mail
Prof. Edward C. Stone, Jr.Data ProviderCalifornia Institute of
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