Alouette 1 and 2 Topside Sounder Electron Density Profile Data in ASCII Format
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This directory contains 4 data files of topside electron density profiles as 
deduced from Alouette 1 (a,b,c) and Alouette 2 topside sounder measurements. 
The data processing was done in the seventies at the Communications Research 
Center in Ottawa, Canada for all except the Alouette1_ne_a data set, which
was processed and submitted to NSSDC by the University of California Los
Angeles (UCLA), Department for Meteorology. The UCLA data set provides data
from 1000km down in steps of 25km. All other data sets provide the electron
density at irregular height intervals. The x- and o-traces were manually scaled 
from the ionograms and the inversion algorithm of J. Jackson was used to 
compute the density profiles from these traces. 

_______________________________________________________________________________   
Data set:	Alouette 1a	b		c	 	Alouette 2
Proc. Center:	UCLA		CRC		CRC		CRC
NSSDC-ID:	62-049A-01P	..T		..U		65-098A-05A
Size/Byte:	6,889,147	12,236,246 	5,989,785	2,833,387
Number of
  Profiles:	15,706		43,614		26,452		9,301
Time Period:	62273-63082	62272-66089	62323-71350	65349-72192
(yyddd)
Satellit orbit
  altitude/km:	1000		1000		1000		500-3000
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Format Description

M               I5      number of records

each record consists of a header and then the electron density profile data

HEADER:

itype           I1      spacecraft identifier
iquality        I2      quality index*
date            I6      yddd            year and day of year
time            I6      hhmmss  hour minutes and seconds
long            F6.1    longitude in degrees
lat             F6.2    latitude in degrees
dip             F6.2    magnetic inclination (IGRF)
L               F5.2    L value
xhi             F6.1    solar zenith angle at 100 km
Rz12            I3      12-month-running mean of sunspot number
IG12            I3      12-month-running mean of IG index
rtec            F6.2    TEC found in data set (units?)
ln(NmF2)        F7.4    IRI value for F2 peak in cm-3
hmF2            F5.1    IRI value for F2 peak height in km
TEC_IRI 	F6.2    IRI value for TEC in TECU
n               I3      number of data points

PROFILE DATA:

n height values:        14I5      h/km*10
n density values:       10I7      ln(Ne/cm-3)*100000 

starting with the highest value (satellite height).

   * Quality index ranges from 0 (best) to 10 (worst), actually 4 to 10 for these 
   data sets, with a most likely value of 6.