TABLE 1 (CONT'D)
CATALOG OF NE, TE AND TI MEASUREMENTS AT JICAMARCA RADAR OBSERVATORY

TIME INTERVAL COVERED TIME INTERVAL COVERED
NO. OF NO. OF
YEAR DATE 75WMT_ = =DATE. = 75WMT._~=— PROFILES YEAR DATE 75WMT_~——DATE—75WMT_—_ PROFILES
1967 SEP 7, 4815 TO SEP 8, 01400 18 1968 JUL 23, 1645 TO JUL 2%, 0745 32
SEP 8, 1428 TO SEP 8, 1645 3 JUL 24, 1145 TO JUL 24, 2345 23
SEP 12, 1700 TO SEP 13, 0930 36 JUL 30, 0800 TO JUL 31, 0730 52
OCT 10, 4228 To Oct 12, 0800 105 AUG 6» 1630 TO AUG 7, 1600 56
OGT 42, 1200 TO OCT 12, 1236 2 AUG 8) 1415 TO AUG 6, 1430 2
OCT 24, 1600 TO OCT 24, 2345 46 AUG 9, 1200 TO AUG 9, 1230 3
OCT 26, 1645 TO OCT 26, 2345 413 AUG 26, 1650 TO AUG 26, 2300 16
OCT 26, 1700 TO OCT 26, 2300 14 AUG 27, 2145 TO AUG 28, 1530 42 i
OCT 30, 1555 TO OCT 3d, 1555 4 SEP 3,'1620 TO SEP 4, 0830 36
NOV 3, 0545 TO NOV 3, 0830 7 SEP 4, 1430 TO SEP 5, 1500 58 |
NOV 16, 1115 TO NOV 16, 1400 5 SEP 13, 1200 TO SEP 13, 1315 3
NOV 16, 1740 TO NOV 16, 2300 10 SEP 23, 1330 TO SEP 23, 1530 4 f
Nov 47, 0500 TO Nov 47, 0715 4 SEP 23, 1845 TO SEP 24, 0900 33 }
NOV 47, 1245 TO NOV 47, 1245 1 OCT 7, 1330 TO OCT 7, 1745 9 |
NOV 20, 1535 TO NOV 20, 1535 4 OCT 8) 1432 TO OCT 9 1607 57 }
NOV 23, 0850 TO NOV 25, 0800 160 OCT 155 1605 TO OCT 16, 0206 30
NOV 28, 1845 TO NOV 23, 0130 19 OCT 16, 1515 TO OCT 17, 0200 34
NOV 29, 0830 TO Nov 29, 0918 2 OCT 18, 1240 TO OCT 18, 1610 24 i
NOV 29, 1215 TO NOV 29, 1245 2 OCT 24, 1100 TO OCT 24, 1435 49 i
Nov 29, 1745 TO NOV 29, 2300 20 OCT 21, 1720 TO OCT 22, 0800 47 f
DEC 12, 41140 TO DEC 12, 1230 3 OCT 22, 1130 TO OCT 22, 1200 2
DEC 12, 1750 TO DEC 13, 0330 23 OCT 22, 1630 TO OCT 23, 0345 36
DEC 13, 1845°TO DEC 13, 1945 5 OCT 31, 1315 TO NOV 1, 1200 58
oEC 1300 TO DEC 19, 2300 84 NOV 1, 1405 TO NOV 1, 2345 22
1200 TO DEC 21, 1300 3 NOV 2, 0200 TO NOV 5, O600 170
DEC 1200 TO DEC 26, 1300 3 NOV 5, 1045 TO NOV 6» 0500 43
EC 4145 TO DEC 27, 1415 6 NOV 6, 1230 TO NOV 6, 1250 2
Ec 4200 TO DEC 29, 1330 4 NOV 6, 1530 10 NOV 6, 2330 415
1968 JAN 1145 TO JAN 2) 1330 5 NOV 19, 1440 TO NOV 24, 0615 97
SAN 1200 TO JAN 3, 1230 2 DEC 3, 1245 TO DEC 3, 2045 20
JAN 4200 TO JAN 4, 1300 3 DEC 3, 2300 TO DEC 4, 1545 40 |
JAN 0930 TO JAN 18, 1330 3 DEC 16, 1545 TO DEC 16, 2133 it
JAN 1625 TO JAN 47, 2345 74 DEC 17, 0930 TO DEG 17, 1100 3
JAN 2220 TO JAN 28, 2300 3 DEC 17, 1400 TO DEC 18, 0800 45 |
FEB 1200 TO FEB 22, 2330 28 DEC 18, 4130 TO DEC 18, 1300 4 |
MAR 0855 TO MAR 13, 1330 8 DEC 20, 1515 TO DEC 21, 0000 29 |
MAR 4600 TO MAR 14, 0806 53 QEC 23, 1640 TO DEC 24, 0015 23 |
APR 1830 TO APR 3, 0830 48 DEC 27, 1530 TO DEC 27, 2345 18
APR 4400 TO APR 4, 0845 55 DEC 30,1405 TO DEC 30, 1405 4
APR 23, 1215 TO APR 24, 0800 40 DEC 30, 1730 TO DEC 30, 2345 15
APR 24, 1200 TO APR 24, 1300 3 1969 JAN 7, 0700 TO JAN 7, 1003 6 i
APR 24, 1645 TO APR 24, 2357 24 JAN 75 1330 TO JAN 8, 0800 ah i
APR 25, 0200 TO APR 25, 0300 17 JAN 28, 1020 TO JAN 28, 1400 3
APR 26, 0130 TO APR 26, 0800 20 JAN 28, 1345 TO JAN 29, 0600 42
APR 29, 2215 TO APR 30, 0300 10 YAN 29, 1120 TO JAN 30, 0800 53
APR 30, 1645 TO APR 30, 2345 20 FEB 17, 1530 TO FEB 19, 1130 105
MAY 2, 0400 TO MAY 2, 0400 6 FEB 24, 1302 TO FEB 24, 1323 2 |
MAY 15, 4745 TO MAY 16) 0745 22 FEB 26, 0630 TO FEB 26, 0330 102 |
MAY 16) 1345 TO MAY 16, 1405 3 FEB 28) 1145 TO FEB 28, 1230 3 |
MAY 17, 0930 TO MAY 18, 0745 44 MAR 4, 1715 TO MAR 6, 0800 93 |
JUN 5, 1230 TO JUN by 1430 44 MAR 17, 1645 TO MAR 18, 1100 62 |
YUN 14, 0945 TO JUN 12, 0830 4h MAR 18, 1650 TO MAR 19, 0900 62
JUN 20, 1250 TO JUN 21, 1500 “5h MAR 19, 1640 TO MAR 205 0900 60
YUN 24, 1030 TO JUN 24, 1200 5 HAR 25, 1145 TO MAR 26, 0830 54
YUN 24, 1630 TO JUN 24, 2245 13 MAR 27, 1315 TO MAR 27, 1600 4
YUN 25, 1245 TO JUN 26, 1550 67 APR 3, 0945 TO APR 3, 1100 5
JUL 4, 1245 TO JUL ty 1300 2 APR 10, 1805 TO APR 10, 2345 24
YUL 8, 1645 TO JUL 8 1705 2 APR 11, 1920 TO APR 11, 2245 44
JUL 9, 0800 TO JUL 10, 1630 69 APR 12) 2020 TO APR 12, 2230 10
JUL 115 1500 TO JUL it, 1500 4 APR 13, 2040 TO APR 13, 2345 14
JUL 12, 4440 TO JUL 12, 1440 1 APR 14) 2030 TO APR 14, 2315 12
JUL 16, 1515 TO JUL 16, 1536 2 APR 15) 1845 TO APR 15, 2345 at
JUL 47, 1220 TO JUL 17, 1250 2 APR 16, 2045 TO APR 16, 2230 8
JUL 22, 1300 TO JUL 225 1450 4 APR 22, 1620 TO APR 2%, 1500 4115
JUL 23, 1100 TO JUL 23, 1300 5 APR 28, 1400 TO APR 29, 1130 50
|
I
10 |



DESCRIPTION AND CATALOG OF IONOSPHERIC F-REGION DATA,
JICAMARCA RADAR OBSERVATORY

(NOVEMBER 1966 - APRIL 1969)
by
W. L. Clark?, J. P. McClure? and T. E. VanZandt?

*Aeronomy Laboratory
National Oceanic and Atmospheric Administration
Boulder, Colorado 80302 U.S.A.

2University of Texas at Dallas
Dallas, Texas 75230 U.S.A.

Introduction

This report basically describes equatorial ionospheric F-region data reduced from the Jicamarca
Radar Observatory (JRO) incoherent scatter observations for particular periods. It lists in catalog
form the times of the observations made during those periods. These F-region data include the
electron concentration, Ne, and the electron and ion temperatures, Te and Ti. The data were inferred
from the incoherent scatter observations of JRO which is located at $11.95 £283.13. JRO is the only
incoherent scatter observatory close to the magnetic equator at 2°N magnetic dip.

For the period 11 November 1966 to 29 April 1969, Ne, Te and Ti data reduced from the JRO
observations are now available both in digital form (on magnetic tape) and in graphical and tabular
form (on microfilm) from the World Data Center A for Solar-Terrestrial Physics. Some results of
similar analyses are already published, in particular the Ne data were presented in graphical form
by McClure et al. [1970] for the period 27 May 1964 to 1 December 1966. Small amounts of data have
appeared in other published papers and reports. lIonospheric drift velocity measurements reduced
from the JRO incoherent scatter observations for the period July 1967 to March 1970 are found in
an earlier UAG Report, Report UAG-17 [Balsley et aZ., 1971].

Measurement Techniques and Analysis Methods

In the Faraday rotation experiment as performed at JRO, two pulses are transmitted simultane-
ously with opposite circular polarization. By comparing the phases of the echoes of the two pulses
as a function of time delay between transmission and reception, the Faraday rotation angle as a
function of height is determined. The electron concentration profile is obtained from the height
derivative of the Faraday rotation angle. This technique is discussed fully by Farley [1969].

See also Evans [1969] for a general review of the incoherent scatter technique

In addition to the measurements for Ne, the temporal autocorrelation function p of the radar
echoes is measured at a series of time separations t. The method by which these measurements are
made is described in considerable detail by Farley et aZ. [1967] and Farley [1969] and will not be
discussed here. Our concern is with the analysis of the measured autocorrelation function to
deduce parameters of the ionospheric plasma.

The JRO measurements of the autocorrelation functions are usually valid only in the ionospheric
F2 layer where almost all of the ions are ionized oxygen (0+). Therefore, the ionic composition has
been approximated by pure 0*, so that the only parameters determined by the present analysis are Te
and Ti. The presence of appreciable concentrations of ions other than 0* will, of course, cause
errors in the derived values of Te and Ti. In particular, near the top of the analyzed height range,
especially at night during solar minimum, there may be appreciable concentrations of ionized hydrogen
(Ht). For small fractional concentrations of H*, the fractional errors in Te and Ti are of the
order of -1 and +1 times the fractional concentration, respectively. Since the fractional con-
centration of Ht in the F2 layer typically increases with height with a scale height of the order
of 150 km, the presence of appreciable concentrations of H* leads to a characteristic and obvious
decrease in Te and an increase in Ti with height.

Examples of theoretical curves of p(t) for pure 0*, two values of Te and three values of Te/Ti
are shown in Figure 1. Two important laws are illustrated. The first law states that the value
of t at p = -0.08 varies as Te? with only a negligible dependence on Te/Ti. The second law states
that the minimum value of p (pmin) in the first negative loop varies approximately linearly with
Te/Ti, as illustrated in Figure 2, but is otherwise independent of Te. The following empirica
formula gives Te/Ti to two decimal places:

Te/Ti = .2305 - 4.666 pmin + 9.23 pmin? (1)

1

|
'

|
I
|
t



RF PERIODS |

bat a

p Factor

RF 9.9 |} —bennna - _|

|
|

H
Dates when nighttime Te / T;’s were obtained
—_ FF

T
|

oT a a T T TT
ON OLJ FM AMS JAS ONDIJFM AMIS JAS ON DIS FMAM YG
1966 1967 1968 1969

Fig. 4. The RF divisor values applied to the p's plotted over the periods of their use
The periods when nighttime Te/Ti values were obtained and used in the determina-
tion of RF are indicated at the bottom of the graph. The mean RF value of 0.9
was used until 11 February 1967. The process used to determine RF is described
in the text.

Format_of Archived Data |

|
|
|
|
|
}
|

An example of the graphical and tabular data as it appears on the microfilm is shown in
Figure 5. The electron concentration data is presented in the upper right graph and in the second
column of the table, labeled Ne. The calculated standard deviation of Ne resulting from the dif-
ferentiation of the Faraday angle is shown as a horizontal bar on the graph (too small to be
visible in this example) and in the first © column, just to the right of the Ne column. It must
be emphasized that < is only the standard deviation due to statistical errors, and that the ac-
curacy of Ne can also be affected by systematic errors. In general, rapid variations of Ne with
either height or time must be treated with caution. For example, in Figure 5 the rapid increase
of Ne with decreasing altitude below 205 km is a systematic error caused by strong scatter from
field-aligned irregularities in the E region. At night, when spread-F irregularities are also
often present, this kind of error can extend to greater heights, Certain other systematic errors
are caused by imperfections in the detectors, particularly at the greatest altitudes where the
signal-to-noise ratio is small. Such imperfections probably cause the weak sinusoidal variation
in Ne from about 450 to 600 km in Figure 5.

The Te and Ti data are presented in the upper left graph and in columns four and six, re-
spectively, in the table. On the graph, the Te points are connected by a solid line and the Ti
points are denoted by circles. The estimated standard deviations resulting from statistica
errors in the measured values of p are shown as horizontal bars on the graph and are listed in the
respective ¢ columns (i.e., columns five and seven) in the table. The column labeled ICD is a
diagnostic code used in the analysis program and can be ignored.

The original magnetic tape archived in the data center is a 9-track, 1600 phase encoded
binary tape. A detailed description of the format is available upon request from WDC-A, and
other types of tapes (such as 7-track binary) may be made available. The tape contains all the
Ne, Te, and Ti results, but does not contain the autocorrelation function data from which they
were obtained. 6



TE/TI VS MINF (RHQ) |
BB po |
t ]
L |
3.0 > 4 |
[ Te/Ti ~ .2305 - 4.666 pmin + 9.23 pmin |
25+ |
Sof
oe [ |
L |
1.55 |
r |
10h |
5L Fs ee ee OS SO OO DO rit]
240 -.5 -.30 -.25 -.20 =15 =.10

MINIMUM RHQ VALUE |

Fig. 2. Te/Ti plotted as a function of pmin (the minimum value of the auto- i]
correlation function). The quadratic equation gives Te/Ti to two
decimal places.

With these two laws, Te and Te/Ti may be found from the autocorrelation data by scaling the
value of t at p = -0.08 and at pmin. Alternatively, Te and Te/Ti can be determined by fitting the
theoretical curves to the measured values of p. The fitting has been done in the present analysis
by adjusting the values of Te and Te/Ti until the best fit in a least squares sense is obtained.
This method has the advantage of using all the data and so reduces the effects of noise

Examination of the actual autocorrelation data along with the functions fitted during the
analysis can provide valuable insight into the quality of the Te and Ti values found at any par-
ticular height and time. Therefore, for each height a plot of measured p's versus t and the corre-
sponding best-fitting function, when actually found, is included on the microfilm. A rather compact.
format was used to enable easy visual comparison of data from one height to the next. A sample
frame is shown in Figure 3


1.0

0.0

\
Tee1500K \

L \

Te=1000K 4

= TE/TIFI.S T |

0.0 5 1.0 1.5 2.0 2.5

Fig. 1.

TAU (MILLISEC@NDS)

Examples of the theoretical autocorrelation function p(t) for Te=1000K and
1500K while Te/Ti = 1.0, 1.5 and 2.0.
ep = -0.08 point is essentially independent of Ti and that the depth of the
first negative loop depends only on Te/Ti.
composition, in this case pure 0+,

These curves illustrate that t at the

These laws assume a constant ion



Figure 3 presents data taken on 17 January 1968 during an integration from 1200 to 1230 hours
(75°W time), as indicated by the title along the left margin. The Figure looks very complex be-
cause data for 32 heights are presented in overlapping form beginning with a height of 145 km and
increasing in 10 km increments to 455 km. This complexity can be avoided by examining one feature
at a time. Consider the bottom row of the Figure. The ordinate is the p axis, ranging from -0.4 to
+0.6, and the abscissa is the t axis, with a tick every 1000 ys. Each tick mark also denotes t = 0
for the height printed sideways, below and to the right of the tick. Each measured value of p is

plotted as a vertical bar centered on the measured value and extending + o (+ one standard deviation).

The sinuous, dotted curves in the plots for 385, 405, 415, 425, 435, and 455 km are the theoretical
autocorrelation functions that best fit the measured values of p. The flattened part of each curve
from 0 to 300 us is a result of an imposed plot limit just above p = 0.6; the actual curves in this
region are as shown in Figure 1.

Often an autocorrelation function could not be fitted because of some deficiency in the data.
If the deficiency was only a lack of data about the first negative loop, a partial analysis was
carried out. A parabola was fitted by least squares to all the points up to and including the first
point whose value of p was $ -0.08. Then the value of t where this parabola intersects the p = -0.08
line (the dashed line below and parallel to the t axis inserted for ease in reading values) was used
to obtain Te. This parabola, when used, is plotted through the data points as a dotted curve, and
the point of intersection is indicated by a circle (e.g., at heights 395 and 445 km in Figure 3).
When even this partial analysis could not be completed, only the data bars are plotted, as for the
first 13 heights (145-265 km) in Figure 3.

In the first row of Figure 3 some of the measured p's are plotted using other symbols. The
x's seen throughout the data in the first eight heights (145-215 km) indicate points that have been
rejected because the space-time geometry of the JRO configuration implies a high probability of
contamination by strong echoes from the equatorial electrojet or by a succeeding pulse. The up
and down arrow symbols (+ ¥) are used for data points that exceed the -0.4 to +0.6 plotter range
for p, which was imposed to avoid confusion with other data.

The p values as used in this analysis and presented on the microfilm have been adjusted in a
manner that must be discussed in some detail. When the preliminary Te and Ti values were plotted,
it was noticed that at night the ratio Te/Ti was usually less than unity by a significant factor
which was statistically independent of height. If this were true, it would require a large heat
‘input to the ion gas with a special height dependence. Since in the nighttime equatorial F2 layer
there is not known to be any large heat input with the required height dependence, we have assumed
that this effect was caused by systematic errors.

In order to study these systematic errors, we first restricted our attention to data taken
between 1900 and 0300 hours (75° W time) since earlier evening data and later morning data often
seemed to be in a transition state between day and nighttime conditions. Heights between 300 and
400 km only were considered in order to reduce the possibility of composition effects. The median
Te/Ti, denoted (Te/Ti)med, within this height range was found for each integration, and the results
were plotted versus time.

Examination of this graph showed periods when the Te/Ti bias seemed to be constant except
for statistical fluctuations. For each of these periods the factor RF (¢ Factor) by which the
p values should be divided so that the median of the (Te/Ti)med's would become 1.0 was calculated.
A graph of the RF values versus date is shown in Figure 4

This normal ization method changes Ti much more than Te, because pmin is changed inversely as
RF but t at p = -0.08 is changed very little. Indeed, the changes in Te are usually within the
estimated standard deviation of Te, although Te always decreases for RF > 1, and vice versa.

This method obviously provides only a first-order correction of Te/Ti. During some periods
there was no nighttime data suitable for a determination of RF. For this reason the last two
months of 1966 data and the first two and one-half months of 1967 data had to be assigned the
mean RF value (namely, 0.9) of all of the other data. The periods when the nighttime values of
Te/Ti were obtained are indicated at the bottom of Figure 4. Furthermore, the statistical fluc-
tuations about (Te/Ti)med over the periods for which each RF was determined are not negligible.
Therefore, in some studies the user may wish to renormalize Te/Ti according to a physical mode’
of temperature structure. This can be done approximately by changing the RF for each profile or
set of profiles, with the aid of Equation (1). Unless the change in RF is large, the changes in
Te are negligible, that is, all of the changes in Te/Ti can be attributed to changes in Ti.



- 53

WORLD DATA CENTER A
for
Solar-Terrestrial Physics

REPORT UAG

DESCRIPTION AND CATALOG
OF IONOSPHERIC F-REGION DATA,
JICAMARCA RADAR OBSERVATORY

(NOVEMBER 1966 - APRIL 1969)

¥
April 1976 Ss



Catalog

Values of Ne, Te, and Ti (normalized as discussed above) along with their associated dates,
times and heights and estimated errors are archived at WDC-A on magnetic tape and microfilm.
Table 1 is a catalog of the observing periods during which measurements were made. Within each
observing period there are one or more radar integrations, each of which is an average of several
thousand samples received over 5 to 10 minutes during sunrise, 15 to 30 minutes in the daytime,
and 15 to 45 minutes at night. The integrations are usually contiguous in time, but occasionally
there are gaps caused by operational difficulties. There are a few time discontinuities on the tape,
resulting from integrations being entered on the magnetic tape in non-chronological order. The
times written on the magnetic tape and microfilm are correct. Approximately 1600 hours of radar
data were analyzed.

Reliability of the Data

The reliability of the present data for any particular aeronomical study can be determined
only by careful consideration of the statistical and systematic errors described in this report.
The Ne data should be adequate for any study consistent with the statistical errors. On the other
hand, the limitation to regions of nearly pure O* and the normalization of Te/Ti are especially
important to the accuracy of the temperature measurements. Judgment of the adequacy of the data
for any particular study or of the correctness of a renormalization procedure must, of course, be
the responsibility of the user.

Acknowledgements

We thank A. S. Oldfather and R. H. Winkler for their very significant contributions in the
Preparation of these data for analysis and we acknowledge the long term efforts of R. Cohen, D. T.
Farley, Jr., J. L. Green, D. L. Sterling and the staff of the Jicamarca Radar Observatory in making
these measurements. The Jicamarca Radar Observatory was a joint operation of the Instituto Geo-
ffsico del Peru and the Environmental Sciences Services Administration (ESSA), a predecessor of NOAA.
The research at Jicamarca was partially supported by the National Aeronautical and Space Administra-
tion (NASA) Fund Transfer R-06-012-008. The National Center for Atmospheric Research (NCAR), which
is sponsored by the National Science Foundation, granted the computer time used for the analyses.

REFERENCES
BALSLEY, B. B. and 1971 Ionospheric Drift Velocity Measurements at Jicamarca,
R. F. WOODMAN Peru (July 1967 - March 1970), Report UAG-17, World

Data Center A for Solar-Terrestrial Physics, NOAA,
Boulder, Colorado 80302 U.S.A., October.

EVANS, J. V., 1969 Theory and Practice of Ionosphere Study by Thomson
: Scatter Radar, Proc. IEEE, 57, 496-530.
FARLEY, D. T., JR. 1969 Faraday Rotation Measurements Using Incoherent Scatter
Radar, Radio Set., 4, 143-152.
FARLEY, D. T., JR. 1967 Temperature and Composition of the Equatorial Ionosphere,
J. P. McCLURE J. Geophys. Res., 72, 5837-5851.
D. L. STERLING, and
J. L. GREEN
McCLURE, J. P., 1970 Ionospheric Electron Concentration Measurements at
D. T. FARLEY, JR., and the Magnetic Equator, 1964-1966, ESSA Tech. Report
R. COHEN ERL 186-AL 4.



800

se ee
<2 Decescatter - 17 vat 1960 1200-9235 AO Boctscatter = 17 vate 1968 1200-1289
700 + 4k -
600 F 7 PF 4
“e 500 - r -
=
: 400 - b 5
300 - a -
200 + ak -
q Cr ee ee ee ee OO iaeuen as on oon oe n 1
"Soo 1000 1500 = 2000 2500 40° 40°
TEMPERATURE [K) Ne [em-3] ere -osos
“ Docwocatter 7 “ue ad 1200 ast mo Doctocatter v7 an 1968 bhatt iad
490 (5) x00(8)
o 428 10.89 .06 1998 28.9007 446 0
0 453 10.99 000 1809 SS HN2 64 6
0 98 4121409 S88 8 at
8 12 0973 46 1262 89 0
62 ) 49 1192 96 0
64 e 4g 1eot 08 0
208 4.96 6 4a 6 0 46
64 8 42 8 0 a0
22 4.93 e 431057 03 0
2% §.90 e 3e Oo 6 40
268 6.77 t) 928 42 1996 % a
be esse t os 39 2s 199 “8
2% 6.08 3 BS $20 6 40
208 7.28 80 368 @ 6 800
293 7.72 163 573 6 8 0 880
38S 8.06 6 Cd 990
8 6.53 es Ld 990
> 333 6.68 St t) 6S 994
. 3B 9.08 a 8 6S 996
33 9.48 ae
3 9.67 se 8
38 9.79 0 40
‘37S 10.06 se
‘383 10.55 sv 8
9G 00.68 @ 4
3. o 6
28 a7 0

Fig. 5.

Te and Ti are plotted against height in the graph at the upper left.

Te is plotted using connected error bars (+ one standard deviation)
while Ti is plotted using circles intersected with error bars. Ne

is plotted against the same height scale in the graph at the upper
right, using connected error bars.

the Figure presents the same information in tabular form.
indicate that no results were obtained.

The table in the lower part of

Zero values
The « column gives the esti-

mated standard deviation of the parameter in the column just to the
left, in the same units.

nostic code and may be ignored.

The "ICD" column contains a computer diag-



— » |
r— x
EF | |
=
rR - | y | .
gf mete Te ll ina
i : an Fj L , ,
Sons “4 + + cot top TH oe
&S ob------ tees bee ld. F |
S
x = x
e uli € $& $€ %$& %€ & [8 |
wa, ~ ‘
s 6
2 TE
= =
2
o£
' t-
Py 60 —
2"E
So =
g o£
= walk
rr
ae
g a
0.0
.
> aL
=z. 7
ee
z°
. |
0.8 1
s z 8 g $ Hy
28

T - Microseconds

Fig. 3. A sample microfilm frame presenting the autocorrelation function found
by the analysis program using the raw data and the best fitting functions.
Data for 32 heights are given on each frame. This frame, for 17 Jan.,
1968, 1200-1230 (75° W time), presents data for heights between 145 and

455 km in 10 kilometer steps. A much more detailed explanation of this
Figure is given in the text.



TABLE OF CONTENTS

Page
INTRODUCTION 1
MEASUREMENT TECHNIQUES AND ANALYSIS METHODS 1
FORMAT OF ARCHIVED DATA 6
CATALOG 8
RELIABILITY OF THE DATA 8
ACKNOWLEDGEMENTS 8
REFERENCES 8

Editor's Note: Instructions for Ordering Data

Requests for data indicated in this catalog should be addressed to:

World Data Center A for Solar-Terrestrial Physics
NOAA
Boulder, Colorado 80302, U.S.A.

Service will tend to be faster the more specific the request can be made. Many users prefer
to discuss their needs first with data center staff by telephone (303-499-1000 X6467, Mr. Conkright
or Miss Brophy) or by Telex 45897 SOLTERWARN BLDR.

Data are provided for cost of copying or under data exchange arrangements. The general price
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Most requests are filled within three weeks.

Price List:
35 mm film copies of microfilm. ...... Chott ee $0.082 per ft.
There are approximately 1400 feet of microfilm.
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There are approximately 6500 profiles.
Tape-to-tape copy of magnetic tape (if blank tape supplied) ...-..-. es 50.00 per tape
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There is a minimum charge of $10.00 per order

Checks must be made payable in U.S. currency to Department of Commerce, NOAA/NGSDC.
and mailed to the address shown above.

ii



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UAG-3 "Observations of Jupiter's Sporadic Radio Emission in the Range 7.6-41 MHz, 6 July 1966
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UAG-5 "Data on Solar Event of May 23, 1967 and its Geophysical Effects", price 65 cents.

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UAG-10 “Atlas of Ionograms", price $1.50.

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UAG-13 "Data on the Solar Proton Event of November 2, 1969 through the Geomagnetic Storm of November
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UAG-14 "An Experimental, Comprehensive Flare Index and Its Derivation for ‘Major’ Flares, 1955-1969",
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UAG-15 "Catalogue of Data on Solar-Terrestrial Physics" (now obsolete).

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UAG-17 "Ionospheric Drift Velocity Measurements at Jicamarca, Peru (July 1967-March 1970)", micro-
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UAG-18 "A Study of Polar Cap and Auroral Zone Magnetic Variations", price 20 cents.

UAG-19 "Reevaluation of Solar Flares 1967", price 15 cents.

UAG-20 "Catalogue of Data on Solar-Terrestrial Physics" (now obsolete).

UAG-21 "Preliminary Compilation of Data for Retrospective World Interval July 26 - August 14, 1972",
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UAG-22 “Auroral Electrojet Magnetic Activity Indices (AE) for 1970", price 75 cents.

UAG-23 "U.R.S.I. Handbook of Tonogram Interpretation and Reduction", price $1.75.

UAG-24 "Data on Solar-Geophysical Activity Associated with the Major Ground Level Cosmic Ray Events
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UAG-25 "Observations of Jupiter's Sporadic Radio Emission in the Range 7.6-41 MHz, 9 September 1968
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UAG-26 “Data Compilation for the Magnetospherically Quiet Periods February 19-23 and November 29 -
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UAG-27 "High Speed Streams in the Solar Wind", price 15 cents.

UAG-28 Collected Data Reports on August 1972 Solar-Terrestrial Events", price (includes Parts 1-3)
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UAG-29 "Auroral Electrojet Magnetic Activity Indices AE (11) for 1968", price 75 cents.

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UAG-31 "Auroral Electrojet Magnetic Activity Indices AE (11) for 1969", by Joe Haskell Allen, Carl
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UAG-32 "Synoptic Radio Maps of the Sun at 3.3 mm for the Years 1967-1969", by Earle B. Mayfield and
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UAG-33 "Auroral Electrojet Magnetic Activity Indices AE(10) for 1967", by Joe Haskell Allen, Carl
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UAG-34 “Absorption Data for the IGY/IGC and IQSY", compiled and edited by A. H. Shapley, National
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WORLD DATA CENTER A
for
Solar-Terrestrial Physics

REPORT UAG - 53

DESCRIPTION AND CATALOG
OF IONOSPHERIC F-REGION DATA,

JICAMARCA RADAR OBSERVATORY
(NOVEMBER 1966 - APRIL 1969)

by

W. L. Clark’, J. P. McClure? and T. E. VanZandt!

tw eronomy Laboratory
National Oceanic and Atmospheric Administration
Boulder, Colorado 80302 U.S.A.

2University of Texas at Dallas
Dallas, Texas 75230 U.S.A.

April 1976 |

Published by World Data Center A for Sy

Solar-Terrestrial Physics, NOAA, Boulder, Colorado
and printed by

BG

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Notes:

(1)

(2)
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Solar-Terrestrial Physics (Solar and
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Phenomena, Flare-Associated Events,
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and Interplanetary Magnetic Phenomena,
Aurora, Cosmic Rays, Airglow):

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TABLE 1

CATALOG OF NE, TE AND TI MEASUREMENTS AT JICAMARCA RADAR OBSERVATORY

TIME INTERVAL COVERED TIME INTERVAL COVERED
NO. OF NO. OF
YEAR DATE 75\WMT DATE 75WMT PROFILES YEAR DATE 75WMT DATE 75WMT PROFILES
1966 NOV 11, G422 TO NOV 11, 1915 50 1967 APR 14, 2145 TO APR 15, 0245 16
NOV 12, 0345 TO Nov 12, 1245 55 APR 16, 1035 TO APR 16, 1226 8
NOV 13, 0530 TO NOV 13, 1145 29 APR 17, 1200 TO APR 17, 1330 4
NOV 14, 1640 TO NOV to, 0605 121 APR 20, 1345 TO APR 20, 1500 3
DEC 1, 1210 TO DEC 2, D430 45 APR 24, 1330 TO APR 21, 2100 45
DEC 2, 0835 TO DEC 2, 1130 7 APR 254 0100 TO APR 25, 0415 7
DEC 7, 1506 TO DEC 7, 1635 2 APR 25) 1215 TO APR 25, 1500 6
DEC 9, 1353 TO DEC 4, 1619 3 APR 26, 1845 TO APR 26, 2130 6
DEC 12, 0912 TO DEC 12, 1240 5 APR 275 0130 TO APR 27, 0330 5
DEC 13, 1715 TO DEC 14, 0930 50 APR 27, 1210 TO APR 28, 0300 25
DEC 14, 1500 TO DEC 14, 1600 3 APR 30, 1900 TO APR 3d, 2336 10
DEC 15, 1830 TO DEC 15, 2300 7 MAY 1, 1960 TO MAY 1, 2230 14
DEC 16, 1615 TO DEG 17, 0300 20 WAY 2, 1020 TO MAY 2, 1605 13
OEC 19, 1745 TO DEC 20, 0315 20 MAY 3, 1130 TO MAY 3, 1315 4
DEC 20, 1645 TO DEC 20, 1845 5 MAY 3, 1530 TO MAY 3, 1615 3
DEC 21, 1625 TO DEC 22, 0245 22 MAY 12, 0000 TO MAY 12, 0536 19
DEC 22, 1430 TO DEC 22, 1830 40 MAY 12, 1415 TO MAY 42, 1505 33
1967 JAN 2, 4400 TO JAN 2, 1800 9 MAY 16, 1600 TO MAY 10, 1615 2
JAN 3, 1036 TO JAN 3, 1530 6 MAY 24, 1150 TO MAY 25, 0336 35
JAN 3, 1900 TO JAN 4, 0330 10 MAY 25, 1045 TO MAY 25, 2406 29
JAN 4s 1015 TO JAN 5, 0215 20 WAY 26, 0030 TO MAY 26, 0200 4
JAN 5, 1020 TO JAN 6, G145 19 MAY 26, 0920 TO MAY 26, 1715 13
JAN 6, 1410 TO JAN 6, 1845 8 MAY 275 1645 TO MAY 27, 2330 15
YAN 105 1036 TO JAN 40, 2000 145 MAY 29, 1210 To MAY 29, 1800 109
JAN 115 1555 TO JAN 12, 0245 17 MAY 30, 1200 TO MAY 3u, 1800 400
JAN 12) 1745 TO JAN 13, 0245 14 MAY 31, 0118 TO MAY 31, 0130 2
JAN 13, 1104 TO JAN 44, 0145 25 MAY 34, 0415 TO MAY 31, 0445 3
JAN 14, 0922 TO JAN 15, 0245 34 MAY 31, 0815 TO MAY 31, 0930 3
YAN 155 0830 TO JAN 16, 0245 34 MAY 31, 1645 TO MAY 31, 1845 6
YAN 19, 1030 TO JAN 20, 0300 29 MAY 34, 2230 TO JUN 1, 0345 7
JAN 20, 1425 TO JAN 20, 1430 2 YUN 1, 1035 TO JUN 1, 1035 4
JAN 20, 1800 TO JAN 24, 0300 14 JUN 4, 1345 TO JUN 1, 1400 2
JAN 22, 1325 TO JAN 22, 2025 84 JUN 1, 1645 TO JUN 14, 1700 2
JAN 23, 1520 TO JAN 24, 0300 20 JUN 2, 4100 TO JUN 2, 1400 4
YAN 24, 1022 TO JAN 24, 2206 23 JUN 2, 15145 TO JUN 2, 1600 2
YAN 25, 0300 TO JAN 25, 0300 4 YUN 8) 1122 TO JUN 8, 1225 2
JAN 345 1903 TO JAN 31, 1926 3 JUN 8, 1545 TO JUN 8, 1545 4
JAN 31, 2200 TO FEB 1, 0840 22 JUN 9, 1545 TO JUN 9, 1545 4
FEB 2, 0300 TO FEB 2, 1045 27 JUN 12, 0910 TO JUN 12, 0945 2
FEB 7, 1330 TO FEB 8, 0406 24 JUN 16, 1590 TO JUN 16, 13808 6
FEB 8, 0930 TO FE8 9, 0500 30 JUN 22, 1530 TO JUN 22, 2315 417
FEB 9, 0845 TO FEB 9, 1100 8 JUN 24, 1345 TO JUN 24, 1415 3
FEB 10, 1000 TO FEB 11, 0500 30 YUN 24, 1715 TO JUN 245 1945 9
FEB 16, 1015 TO FEB 17, 0245 29 JUN 275 1145 TO JUN 27, 1215 3
FEB 17, 0845 TO FEB 18, 0530 44 JUL 6, 1100 TO JUL 6, 1600 9
FEB 21, 1545 TO FEB 21, 1700 4 JUL 7, 0950 TO JUL 7, 1556 13
FEB 22, 1130 TO FEB 22, 1505 9 YUL 11, 2300 TO JUL 44, 2300 1
FEB 23, 0905 TO FEB 23, 0950 4 YUL 12, 0200 TO JUL 12, 0406 2
FEB 23, 1200 TO FEB 24, 0330 34 JUL 43, 0405 TO JUL 13, 0405 4
FEB 24, 0830 TO FEB 24, 1315 tt JUL 43, 0725 TO JUL 43, 0725 1
FEB 24, 1600 TO FEB 25, 0200 16 JUL 13, 1550 TO JUL 13, 1550 i
FEB 27, 1200 TO FEB 27, 1230 2 JUL 17, 4400 TO JUL 20, 0750 149
FEB 26, 4130 TO FEB 28, 1230 2 YUL 24, 0400 TO JUL 21, 0490 a
MAR 4, 0915 TO MAR 4, 1757 120 JUL 21, 0800 TO JUL 21, 0806 1
MAR 3, 0900 TO MAR 3, 0900 1 JUL 24, 2305 TO JUL 24, 2305 rl
MAR 3 1145 TO MAR 3, 1330 4 JUL 25, 2000 TO JUL 26, 0800 33
MAR 3, 1600 TO MAR 4, 0345 25 JUL 34, 0920 TO JUL 31, 0940 2
MAR 6, 1215 TO MAR 6, 1236 2, JUL 345 1630 TO JUL 31, 1730 2
MAR 7, 0930 TO MAR 7, 1230 a AUG 4, 2230 TO AUG 2, 0200 7
MAR 22. 1400 TO MAR 22, 1708 6 AUG 2, 0500 TO AUG 2, 0915 412
MAR 22, 2030 TO MAR 22, 2030 1 AUG 2, 1615 TO AUG 3, 1200 49
MAR 23, 1100 TO MAR 23, 2230 43 AUG 7, 2040 TO AUG 7, 2040 1
MAR 24, 0100 TO MAR 24, 0400 4 AUG 9, 2330 TO AUG 9, 2330 1
MAR 27, 1045 TO MAR 27, 1700 48 AUG 10, 1500 TO AUG 11, 0415 19
MAR 295 1400 TO MAR 29, 1400 1 AUG 11, 0935 TO AUG 12, 0750 52
HAR 29, 1630 TO MAR 29, 1800 2 AUG 14, 1300 TO AUG 47, 1030 157
MAR 30, 1530 TO MAR 31, 0330 24 AUG 17, 2311 TO AUG 17, 23141 4
MAR 31, 1445 TO MAR 31, 1230 3 AUG 23, 1145 TO AUG 23, 1515 5
APR 5, 1000 TO APR 5, 1730 15 AUG 28, 1745 TO AUG 29, 1200 48
APR 12, 1430 TO APR 13, 0330 27 AUG 29, 1510 TO AUG 31, 0900 104
APR 13) 1030 TO APR 44, 0115 33 SEP 1, 1450 To SEP 1, 1946 59
APR 14, 1115 TO APR 14, 1445 8 SEP 5, 1845 TO SEP 6, 0100 16



UAG-35 "Catalogue of Digital Geomagnetic Variation Data at World Data Center A for Solar-Terrestrial

Physics", prepared by Environmental Data Service, NOAA, Boulder, Colorado, July 1974, 20 pages,
price 20 cents.

UAG-36 "An Atlas of Extreme Ultraviolet Flashes of Solar Flares Observed Via Sudden Frequency Devia~
tions During the ATM-SKYLAB Missions", by R. F. Donnelly and £. L. Berger, NOAA Space Environ-
ment Laboratory, Lt. J. D. Busman, NOAA Conmissioned Corps, B. Henson, NASA Marshall Space
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UAG-37 “Auroral Electrojet Magnetic Activity Indices AE(10) for 1966", by Joe Haskell Allen, Carl C.
Abston and Leslie D. Morris, National Geophysical and Solar-Terrestrial Data Center, Environ-
mental Data Service, December 1974, 142 pages, price 75 cents.

UAG-38 "Master Station List for Solar-Terrestrial Physics Data at WOC-A for Solar-Terrestrial Physics",
by R. W. Buhmann, World Data Center A for Solar-Terrestrial Physics, Juan D. Roederer, Univer-
sity of Denver, Denver, Colorado, M. A. Shea and D. F. Smart, A.F.C.R.L., Hanscom AFB, Massa-
chusetts, December 1974, 110 pages, price $1.60.

UAG-39 "Auroral Electrojet Magnetic Activity Indices AE(11) for 1971", by Joe Haskell Allen, Carl C.
Abston and Leslie D. Morris, National Geophysical and Solar-Terrestrial Data Center, Environ-
mental Data Service, February 1975, 144 pages, price $2.05.

UAG-40 "H-Alpha Synoptic Charts of Solar Activity For the Period of Skylab Observations, May, 1973-
March, 1974", by Patrick S. McIntosh, NOAA Environmental Research Laboratory, February 1975,
32 pages, price 56 cents.

UAG-41 "H-Alpha Synoptic Charts of Solar Activity Durina the First Year of Solar Cycle 20 October,
1964 ~ August, 1965", by Patrick S. McIntosh, NOAA Environmental Research Laboratory, and
Jerome T. Nolte, American Science and Engineering, Cambridge, Massachusetts, March 1975,
25 pages, price 48 cents.

UAG-42 "Observations of Jupiter's Sporadic Radio Emission in the Range 7.6-80 MHz 10 December 1971
through 21 March 1975", by James W. Warwick, George A. Dulk, and Anthony C. Riddle, Depart-
ment of Astro-Geophysics, University of Colorado, Boulder, Colorado 80302, April 1975,
49 pages, price $1.15.

UAG-43 "Catalog of Observation Times of Ground-Based Skylab-Coordinated Solar Observing Programs",
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159 pages, price $3.00.

UAG-44 "Synoptic Maps of Solar 9.1 cm Microwave Emission from June 1962 to August 1973", by Werner

Graf and Ronald N. Bracewell, Radio Astronomy Institute, Stanford University, Stanford,
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UAG-45 “Auroral Electrojet Magnetic Activity Indices AE(11) for 1972", by Joe Haskell Allen, Carl C.
Abston and Leslie D. Morris, National Geophysical and Solar-Terrestrial Data Center, Environ-
mental Data Service, May 1975, 144 pages, price $2.10.

UAG-46 "Interplanetary Magnetic Field Data 1963-1974", by Joseph H. King, National Space Science

Data Center, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, June 1975, 382
pages, price $2.95.

UAG-47 “Auroral Electrojet Magnetic Activity Indices AE(11) for 1973", by Joe Haskell Alien, Carl C,
Abston and Leslie D. Morris, National Geophysical and Solar-Terrestrial Data Center, Environ-
mental Data Service, June 1975, 144 pages, price $2.10.

UAG-48A "Synoptic Observations of the Solar Corona during Carrington Rotations 1580-1596 (11 October
1971 - 15 January 1973)", [Reissue with quality images] by R. A. Howard, M. J. Koomen, D. J.
Michels, R. Tousey, C. R. Detwiler, D. E. Roberts, R. T. Seal and J. D. Whitney, E. 0. Hulbert.
Center for Space Research, NRL, Washington, D. C. 20375 and R. T. and S. F. Hansen, C. J.
Garcia and E. Yasukawa, High Altitude Observatory, NCAR, Boulder, Colorado 80303, February 1976,
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UAG-49 "Catalog of Standard Geomagnetic Variation Data", prepared by Environmental Data Service, NOAA,
Boulder, Colorado, August 1975, 125 pages, price $1.85.

UAG-50 "High-Latitude Supplement to the URSI Handbook on Ionogram Interpretation and Reduction", by
W. R. Piggott, British Antarctic Survey, c/o SRC, Appleton Laboratory, Ditton Park, Slough,
England, October 1975, 292 pages, price $4.00.

UAG-51 "Synoptic Maps of Solar Coronal Hole Boundaries Derived from He IT 3044 Spectroheliograms from

the Nanned Skylab Missions". by J.D. Bohlin and on Me Rubenstein, E. 0. Hulbert Center for

Space Research, Naval Research Laboratory, Washington, D. C. 20375 U.S.A., November 1975,

30 pages, price 54 cents.

UAG-52 “Experimental Comprehensive Solar Flare Indices for Certain Flares, 1970-1974", compiled by
Helen W. Dodson and E. Ruth Hedeman, McMath-Hulbert. Observatory, The University of Michigan,
895 Lake Angelus Road North, Pontiac,-Michigan 48055 U.S.A., November 1975, 27 pages, price
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USCOMI-NOAA-ASHEVILLE-h~76-100