| DATA_SET_DESCRIPTION |
This data set contains electron parameters in the PLS
energy range (10-5950 eV) at Uranus during the Voyager 2
encounter. Parameters are calculated in several ways. Total
moment density and temperature are given. Each electron
spectrum is also fit with a thermal component and 1-3 hot
components depending on how many Maxwellians are needed to
fit the entire distribution. The moment density and
temperature of the hot component is calculated after the
thermal component is subtracted from the spectrum. The
CHI-Square value for each fit is given. The spacecraft
charge is not calculated consistently, and may result in
factor of 2-3 errors in the thermal electron density. Data
is unreliable inside 5 RU and in the occultation regions.
At Uranus measurements were taken using both a long and a
short integration time. Each 48 SEC measurement frame
contained either an E1-Short and an E2-Long measurement or
an E2-Short and an EI-Long. To reduce systematic errors,
complete electron spectra were obtained only by combining
two long or two short spectra. The instrument threshold is
at a density of about 0.001 CM-3; thus fits which yield
data close to this value should be treated with caution.
Flags in the data indicate whether the full analysis could
be performed and if the data was contaminated by LECP
stepping. A complete description of this data set is in
Sittler et al. (1987).
THE PARAMETER DEFINITIONS ARE:
NAME TYPE DEFINITION
TIME A*24 YR,MON,DAY,HR,MIN,SEC,MSEC
IFLY ' Flag = 0 for Cruise, 1 for Magnetosphere, -2
for rough moment estimate only, -5 for no
analysis
LECPF ' Flag = 1 for LECP contamination, 0 otherwise
EDATA(1) R*4 THBN(angle between DCUP normal and B vector)
2 ' RNE moment electron density (/CM**3)
3 ' RTE ' ' temperature (eV)
4 ' PHISC spacecraft potential (Volts)
5 ' RNC cold electron density (/CM**3)
6 ' SGNC standard deviation of RNC (/CM**3)
7 ' RTC cold electron temperature (eV)
8 ' SGTC standard deviation of RTC (eV)
9 ' CHIC CHI-Square of cold fit
10 ' RNH1 1st hot electron density (/CM**3)
11 ' SGNH1 standard deviation of RNH1 (/CM**3)
12 ' TH1 1st hot electron temperature (eV)
13 ' SGTH1 standard deviation of TH1 (eV)
14 ' CHIH1 CHI-Square of 1st hot fit
15 ' RNH2 2nd hot electron density (/CM**3)
16 ' SGNH2 standard deviation of RNH2 (/CM**3)
17 ' TH2 2nd hot electron temperature (eV)
18 ' SGTH2 standard deviation of th2 (eV)
19 ' CHIH2 CHI-Square of 2nd hot fit
20 ' RNH3 3rd hot electron density (/CM**3)
21 ' SGNH3 standard deviation of RNH3 (/CM**3)
22 ' TH3 3rd hot electron temperature (eV)
23 ' SGTH3 standard deviation of TH3 (eV)
24 ' CHIH3 CHI-square of 3rd hot fit
25 ' CHI CHI-Square for total fit
26 ' RNH moment hot electron density (/CM**3)
27 ' RTH moment hot electron temperature (eV)
In computing RNH1,TH1 we used the 3rd to 7th channels above
the breakpoint energy EB1 and subtracted the cold component
FC from FE (observed) before doing the fit. In reality this
fit was done iteratively between the cold and hot component
fits (FC=FE-FH and FH=FE-FC etc.). A similar approach was
used in computing RNH3,TH3 for which a Maxwellian fit was
done to those channels above EB2. The parameters RNH2,TH2
were fit to the upper 5 (3 MIN) channels (generally above
EB2). This fit was primarily done to allow proper
estimation of FE to the high energy portion of the
spectrum. In many cases there are not sufficient points to
compute RNH3,TH3 AND RNH2,TH2 do provide a fair
representation of the spectrum. If RNH1=RNH2=RNH3 then you
should not use the 2nd and 3rd fit parameters. Values of
1.E32 indicate that the parameter could not be obtained
from the data using the standard analysis technique.
Additional information about this dataset 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 Sittler et al. (1987) and a complete instrument
description can be found in Bridge (1977).
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