SAMPEX PET 6-Second Rate Data Documentation

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This data set consists of 6-second particle rates from the PET instrument. The data set covers the complete mission, from launch through 2004-182. The rates are not calibrated or converted into physical units. Calibrated particle intensities are also available.

The data are derived from the SAMPEX RS Set data, documented in the SAMPEX NGDF Data File Description.

The time-stamps for the attitude/orbit (PS Set) data have been synced (in ground data processing) with the time-stamps for these 6-second rate data, and with the time-stamps for the particle intensity data.

Thus, the timestamps in each of these data sets may be used to associate the appropriate attitude/orbit data with each 6-second intensity or rates data record.

In addition, the intensity, attitude/orbit, and rates data have been filled so that they all contain the same number of records per day.

The Basic Rates are counts accumulated over 6-second intervals. The multiplexed rates are sampled during 1 or 2 6-second periods every 96 seconds. Thus, their units are also counts/6 seconds, but the data are valid only once (or twice) per 16 data records.

More information on the SAMPEX spacecraft, instruments, operations, and the science data may be found in the SAMPEX Mission and Instrument Documentation.

Description of each data field

  1. year:
    Four-digit year
  2. day:
    Day of year (starting at 1)
  3. hr:
    Hour of day
  4. min:
    Minute of hour
  5. sec:
    Second of minute
  6. fp_year:
    Year, floating-point
  7. fp_doy:
    Day of year, floating-point
  8. sec_of_day:
    Second of day
  9. Subcom:
    The subcom defines the multiplexed rates for HILT, PET, and PET. Valid values are 6 thru 21. Thus, each subcom cycle lasts 16×9 = 96 seconds.

    Basic Rates

  10. PHI:
    Protons, 28-60 MeV/nucleon, 6 second time resolution. Sometimes no upper limit.
  11. EHI:
    Electrons, ~4-15 MeV, 6 second time resolution. Sometimes no upper limit.
  12. PLO:
    Protons, 19-28 MeV/nucleon, 6 second time resolution.
  13. ELO:
    Electrons, 2-6 MeV, 6 second time resolution.
  14. EWG:
    Electrons, wide geometry, 4-30 MeV, 6 second time resolution. Sometimes no upper limit.
  15. Livetime:
    Instrument Livetime, 732/ 6 seconds = 99.7%
  16. PEN:
    Protons, >85 MeV, Electrons > 30 MeV, 6 second time resolution.
  17. RNG:
    Protons > 60 MeV, Electrons >15 MeV, 6 second time resolution.

    Multiplexed Rates

  18. P1ADC:
    P1ADC detector singles rate. Electrons > 400 keV, protons > ~2 MeV
    Read out when Subcom=6,14
  19. ADCOR:
    Counting rate for logical "OR" of and ADC trigger. Electrons > 400 keV, protons > ~2 MeV
    Read out when Subcom=7,15
  20. P2ADC:
    P2 detector singles rate. Electrons > ~800 keV, protons > 5 MeV
    Read out when Subcom=8,16
  21. AL:
    Low level anticoincidence trigger. Logical "OR" of guard rings on P3 to P8 detectors. Counting rate of particles triggering the lower-level guard discriminators (0.3 MeV).
    Read out when Subcom=9,17
  22. P3ADC:
    P3 detector singles rate. Electrons > ~3 MeV, protons > 5 MeV
    Read out when Subcom=10,18
  23. AH:
    High-level anticoincidence trigger. Logical "OR" of guard rings on P3 to P8 detectors. Counting rate of particles triggering the upper-level guard discriminators (1.2 MeV for A4-A8, ~5 MeV for A3).
    Read out when Subcom=11,19
  24. P47ADC:
    P4-7 detectors singles rate. He ~75-90 MeV/nuc. The summed outputs of P4 thru P7 are read out by a single ADC.
    Read out when Subcom=12,20
  25. PET_HAZ:
    Rate of Hazard events: ADC trigger close to previous ADC trigger.
    Read out when Subcom=13,21
  26. P4:
    P4 detector discriminator trigger rate. Electrons > 15 MeV, H, He > 60 MeV/nuc.
    Read out when Subcom=6
  27. P5:
    P5 detector discriminator trigger rate. Electrons > 18 MeV, H, He > 64 MeV/nuc.
    Read out when Subcom=7
  28. P6:
    P6 detector discriminator trigger rate. Electrons > 22 MeV, H, He > 70 MeV/nuc.
    Read out when Subcom=8
  29. P7:
    P7 detector discriminator trigger rate. Electrons > 26 MeV, H, He > 77 MeV/nuc.
    Read out when Subcom=9
  30. P8:
    P8 detector discriminator trigger rate. Electrons > 30 MeV, H, He > 85 MeV/nuc.
    Read out when Subcom=10
  31. A3L:
    A3 guard ring lower-level (0.3 MeV) discriminator trigger rate.
    Read out when Subcom=11
  32. A3H:
    A3 guard ring upper-level (5 MeV) discriminator trigger rate.
    Read out when Subcom=12
  33. A4L:
    A4 guard ring lower-level (0.3 MeV) discriminator trigger rate.
    Read out when Subcom=13
  34. A4H:
    A4 guard ring upper-level (1.2 MeV) discriminator trigger rate.
    Read out when Subcom=14
  35. A57L:
    A5,7 guard rings lower-level (0.3 MeV) discriminator trigger rate.
    Read out when Subcom=15
  36. A57H:
    A5,7 guard ring upper-level (1.2 MeV) discriminator trigger rate.
    Read out when Subcom=16
  37. A68L:
    A6,8 guard ring lower-level (0.3 MeV) discriminator trigger rate.
    Read out when Subcom=17
  38. A68H:
    A6,8 guard ring upper-level (1.2 MeV) discriminator trigger rate.
    Read out when Subcom=18
  39. P1A:
    P1 detector discriminator trigger rate. H, He, some electrons >4 MeV.
    Read out when Subcom=19
  40. P3A:
    P3 detector discriminator trigger rate, 2.8 MeV.
    Read out when Subcom=20
  41. P3B:
    P3 detector discriminator trigger rate, 12 MeV.
    Read out when Subcom=21

    Attitude/Orbit

    A subset of the SAMPEX attitude/orbit data. For more, see the     Complete attitude/orbit data set.
  42. GEO_Long
    Longitude in GEO coordinate system (0 to 360 degrees).
  43. GEO_Lat
    Longitude in GEO coordinate system (0 to 360 degrees).
  44. L_Shell
    L-shell parameter.
  45. Invariant_Lat
    Invariant latitude (degrees).
  46. Pitch
    Pitch angle of a particle heading down the instrument boresight (i.e., angle between S/C z-axis and (-1) times the local magnetic field vector), in degrees.
  47. Magnetic_Lat
    Algebraic magnetic latitude (degrees).
  48. Mag_Local_Tm
    Local time at magnetic equator along current field line (hr) ECD.
  49. Att_Flag
    Flag, data quality flag indicating source of attitude information (Applies only to pitch angle for the attitude/orbit data subset included here).
    Executive summary: flag =0,1,100, or 101 means attitude is OK. Other values indicate attitude is not OK.