Data Set:  9-second/18-second Electron Moments (N, V, T, H) 
Experiment Directory Name: fast_electrons_gsfc

NSSDC ID:  SPMS-00119
  OLD ID:  77-102A-02D

Time Span: 1977-10-27 to 1978-12-31
Filenames: i1_9s_18s_fast_el_mom_YYMMDD.txt

DESCRIPTION:

These data consist of experimenter-supplied electron moments from the Vector
Electron Spectrometer on ISEE-1. Each data record consists of the year, day of
year (January 1 = Day 0), milliseconds of day, the geocentric radius of the
spacecraft location, spacecraft position in GSE coordinates, the electron
density (cm^-3), electron temperature (degrees K), parallel-to-perpendicular
temperature anisotropy, GSE components of the bulk flow velocity (cm/sec), GSE
components of the heat flux vector (erg cm^-2 sec^-1), GSE components of the
magnetic field from the Data Pool magnetometer data (nT), and the spacecraft
potential (eV). The time corresponds to the start of the data collection
interval, i.e., the start of the spin. The time between data records is
approximately 9.12 seconds or 18.24 seconds depending on the bit rate. This is
because although data are collected over a single 3-second spin, data are then
read out over a multiple spins. Since the magnetic field data are at a
resolution of 64 seconds, the same magnetic field record was used multiple
times; no interpolation was done on the magnetic field data values. The
electron temperature value is derived from one-third of the trace of the
pressure tensor, i.e., it is equal to [T(parallel) + 2*T(perpendicular)]/3.


DOCUMENTATION:

Documentation for NSSDC Data Set 1977-102A-02D (9s/18s Electron Moments) From
ISEE-1 Vector Electron Spectrometer (PI: K. W. Ogilvie, GSFC)

This is an ASCII version of the original binary data set. It was generated
at NSSDC in March, 2002 by H. Kent Hills by converting from the original
binary dataset. The precision of the original binary values was kept, at the
price of slightly increased data volume. (The original data set precision did
not make use of the full precision available in the binary representation.)
No other change has been made in the data set. The following data set
description is taken from the original description supplied by the data
provider.

Word  1     year
Word  2     decimal day (Jan 1 = day 0)
Word  3     millisecs of day
Word  4     geocentric radius of s/c location
Word  5     gse  x
Word  6     gse  y
Word  7     gse  z
Word  8     electron density (el/cm**3)
Word  9     electron temperature (degrees K) = (Tpar + 2Tperp)/3
Word 10     parallel to perpendicular temperature anisotropy
Word 11     bulk flow ux (gse, cm/sec)
Word 12     bulk flow uy (gse, cm/sec)
Word 13     bulk flow uz (gse, cm/sec)
Word 14     heat flux hx (gse, ergs/cm**2/sec)
Word 15     heat flux hy (gse, ergs/cm**2/sec)
Word 16     heat flux hz (gse, ergs/cm**2/sec)
Word 17     data pool tape 64 sec mag field bx (gse, nT)
Word 18     data pool tape 64 sec mag field by (gse, nT)
Word 19     data pool tape 64 sec mag field bz (gse, nT)
Word 20     s/c potential (elec volts)

********************************************************
NOTE:
Time corresponds to the start of collection, i.e., the start of the spin. Time
between records will be approx 9.12 sec or 18.24 sec depending on the bit
rate. This is because although data are collected over a single spin (3 sec),
data are then read out over multiple spins.

Because our data reads out more often than the magnetic field data used, i.e.
64 sec for the magnetic field, vs. approx 9.12 or 18.24 sec for our data, the
same magnetic field record was used multiple times. No interpolation was
done on the magnetic field record.

Under certain conditions some of the above should not be used. Magnetic Field
bx, by, bz values of -0.1E+10 should be skipped, as should any 0.0 readouts,
and readouts equal to 1.7E36 or -1.7E36.

If questions arise, plase contact Franklin Ottens (301-286-6674), or Richard
Fitzenreiter (301-286-6825).

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The binary version of this dataset was received by NSSDC in December, 1992 as
a reprocessed version of an earlier dataset (using the same ID). It was 
received on a single tape, which was a replacement for the 40 tapes of the 
earlier dataset.