PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2000-04-10 NOTE = "This file describes the contents of this directory." END_OBJECT = TEXT END PEPE CODMAC level 2 data format (F.Crary, 13 JAN 02) There is one file per product, per day. Each file contains measurements which begin between 00:00:00 on that day and 00:00:00 on the following day (SCET). Measurement numbers will be the same for all data products, i.e. if a measurement of ELC data is missing, the measurement numbers in the ELC file will skip the appropriate number. The files will be flat, binary data, with a fixed series of values repeated as many times as necessary. This format only describes the data products generated during and around the encounter with P/19 Borrelly. File names are of the form xxxyyddd.dat where: xxx = elc Electron data hsk Housekeeping data ion Ion singles data log Ion logicals data mq Ion mass over charge data tof Ion time of flight data yy = 01 Year ddd = Day of year Electron data are the flux of electrons as a function of energy and angle. Housekeeping data are selected housekeeping values of use in analysis of the PEPE data. Ion singles are the flux of all ions as a function of energy and angle. (In terms of instrument operations, these are the number of start counts in the time of flight system, regardless of the ion's time of flight, or even whether or not a valid stop signal was measured.) Ion mass over charge data are the flux of selected ions as a function of energy and angle. The ions are selected on the basis of time of flight (i.e. composition) For example, the MQ 0 data are the energy/angle spectra of all proton. The 15 MQ bins have a one-to-one correspondence to time of flight, but not necessarily to species (e.g. most of the counts in MQ bin 1 are He++, but some protons also fall into the MQ 1 time of flight bin.) TOF spectra are the flux of ions as a function of time of flight (related to composition) and summed over all energies and angles. All integers are unsigned =========================================================================== Electron (elc*) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Offset time Integer 2 Seconds from start of measurement Energy Step Integer 2 Energy step number Elevation Step Integer 2 Elevation step number Data, Azimuth 1 Integer 4 Counts in azimuth 1 Data, Azimuth 2 Integer 4 Counts in azimuth 2 Data, Azimuth 3 Integer 4 Counts in azimuth 3 Data, Azimuth 4 Integer 4 Counts in azimuth 4 There are 28 bytes per row and 256 rows per measurement =========================================================================== Ion singles (ion*) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Offset time Integer 2 Seconds from start of measurement Energy Step Integer 2 Energy step number Elevation Step Integer 2 Elevation step number Data, Azimuth 1 Integer 4 Counts in azimuth 1 Data, Azimuth 2 Integer 4 Counts in azimuth 2 Data, Azimuth 3 Integer 4 Counts in azimuth 3 Data, Azimuth 4 Integer 4 Counts in azimuth 4 Data, Azimuth 5 Integer 4 Counts in azimuth 5 Data, Azimuth 6 Integer 4 Counts in azimuth 6 Data, Azimuth 7 Integer 4 Counts in azimuth 7 Data, Azimuth 8 Integer 4 Counts in azimuth 8 There are 44 bytes per row and 512 rows per measurement =========================================================================== Logicals (LOG) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Offset time Integer 2 Seconds from start of measurement Energy Step Integer 2 Energy step number Elevation Step Integer 2 Elevation step number Data, Coarse starts Integer 4 Start counts in coarse azimuths Data, Fine starts Integer 4 Start counts in fine azimuths Data, Stops Integer 4 Stop counts Data, Resets Integer 4 Resets There are 28 bytes per row and 128 rows per measurement =========================================================================== Mass over charge (MQ) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Offset time Integer 2 Seconds from start of measurement Energy Step Integer 2 Energy step number Energy step Data, bin 0 Integer 4 Counts in M/Q bin 0 Energy step Data, bin 1 Integer 4 Counts in M/Q bin 1 Energy step Data, bin 2 Integer 4 Counts in M/Q bin 2 Energy step Data, bin 3 Integer 4 Counts in M/Q bin 3 Energy step Data, bin 4 Integer 4 Counts in M/Q bin 4 Energy step Data, bin 5 Integer 4 Counts in M/Q bin 5 Energy step Data, bin 6 Integer 4 Counts in M/Q bin 6 Energy step Data, bin 7 Integer 4 Counts in M/Q bin 7 Energy step Data, bin 8 Integer 4 Counts in M/Q bin 8 Energy step Data, bin 9 Integer 4 Counts in M/Q bin 9 Energy step Data, bin10 Integer 4 Counts in M/Q bin 10 Energy step Data, bin11 Integer 4 Counts in M/Q bin 11 Energy step Data, bin12 Integer 4 Counts in M/Q bin 12 Energy step Data, bin13 Integer 4 Counts in M/Q bin 13 Energy step Data, bin14 Integer 4 Counts in M/Q bin 14 There are 70 bytes per row and 64 rows per measurement =========================================================================== Time of flight (TOF) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Data, bin 0 Integer 4 Counts in TOF bin 0 Data, bin 1 Integer 4 Counts in TOF bin 1 ... Data, bin 1023 Integer 4 Counts in TOF bin 1023 There are 4102 bytes per row and one row per measurement =========================================================================== Housekeeping (HSK) data format: Name Type Bytes Description =========================================================================== Measurement number Integer 2 Measurement number from start of day Time Integer 4 Measurement start time, sec. from J2000 Time Integer 4 Measurement start time, SCLK Integration time Integer 2 Integration time per sample, multiples of 28.62 ms (legal values are 1, 10 and 20) SC_IPS_ON Integer 2 Ion propulsion system thrust level [mN] SC_IPS_LEVEL Float 4 Ion propulsion system thrust level [mN] SC_RSC_SUM Float 4 RSC thruster on time, [sec] SC_SUN_AZ Integer 2 Sun azimuth, s/c coordinates [deg] SC_SUN_EL Integer 2 Sun elevation, s/c coordinates [deg] There are 26 bytes per row and one row per measurement