ON THE BEHAVIOUR OF THE IONOSPHERE DURING SUDDEN IONOSPHERIC DISTURBANCES.

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP80T00246A005400350007-7
• Release Decision: RIFPUB
• Original Classification: K
• Document Page Count: 5
• Document Creation Date: December 21, 2016
• Document Release Date: January 5, 2009
• Sequence Number: 7
• Content Type: REPORT

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N? a ?:.~.VITCII
L
ON THE &H.. rIOUR OF T:~ ~ ~~? .:`~F'~?=?h DU .ING UDDEN
ICITC~, ?..:.iIC L l r~l iiiil'~CE .
r: The ionization equation vas solved for thdd t1eot:.?cn
production function linear -:ith time. It is indicated that
the development of a flare in H., light is not reprosc-n-
tative for an aotiva radiation of flt;re. The metrod of de-
termination of the value -to , 1 and of the coruse ciith
time of solar flare radiation att19' for the ionosphcre is
suggested.
I .
Relative electron density varintions during' sudden ionvsr
rie disturbancc-s ( SID'S ) due to ccotivo emiaE;ion of solar
flares are described by the well-known equation:
d IS j4 . I(t)- - (11--- (- )
d t rt o To IIo
Here N0 is electron d::nsity and Io - function of the
al-actron production (both - at the moment of Si0 beginning).
? : ecntly a solution of ..cequation (1) has been found
/1,2/ forl(t)/Ic, in the form of a rectangular pulse. If is
a linear Cunction of time, i.e. I (t) /I0 1 o+ T
ttr1O-t:f31 3 Vo U_/Jl?? 3U?J
No r+l/3 /V10- c fll/3 . Vo/TT-I' IT10- 1,1) 1"13 U?/ V
he:r r
c
(2)
T is a partlDict%r ahareoterizind the
(1)
p correspond to
to a docr::asing one
variations of I(t)/Io ; the valuos of
an increasing I(t)/Io and T 4.0
N(0)
for intervals having different
u , v;u v' are the i r funct ions 2
rith argument Z B2 , (po +
ar: the same owns pith argument
vole---s of T;
una their dwrivntives ?~
uc: vo tulo v1C
PU
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Lots us consider some applications of those relations.
It seems interesting to find out if the d?belopment of a
flare in H light is representative for an active flare
omission /4,5/. The development curvos of f
lnros (the course
with time of intensity and emission flow in H light)
were approximated by the broken lines.
Electron density variations ' ere: conput:~d by means of
equation (2) assur:ing that time variations of active emission
are the same as in }I light, but ith a grouter amplitude
These calculations 'sere made for i'lart s 3l/VIII-5?,28/VI77?57,
3/IX-57 and 23/)rI-,,q7,. On thr, otter hand, electron density va-
riations wore determined by known m~:asurcd values of f rain
/6/ to compare them with observations. F'ip.l Pive:s an. ::temple
of comparison of observed values of r(t) No ',ith those oom,
putod by a described method. Graphs of fig. 1 shoes that the
development of the flare in H light is not represontativc.
for the active emission. :;pparcntly this emission is X-ray
radiation of the flare. The r:)vorse problem is also of a grL:at
interest. The ionospheric parameter Z. and the course with
time of active emission can be determined if there are conti-
nuous monsurements of N (t )Ao during Si (for 1)- Tegion by
measurements of absorption, f min o . t ; e . ) ! illy, suppois ing
that an active omission In initial. stage of development of
the flare can be approsimate,d by ,triangular pulse ire: can find
Td and parameters dote rrlinl.nf; that triangle, they are: tm
time delay of electron density ficsimum Tim/No relatively to
the top of the triangles; To and Tl - values of T for different
sides of triangle; to - the total time. of I(tyIo growth. To
solve this problem it is ri.:cessary to hove fivt equations:
Nr_
I TO
(ToltolTlr.1 qa)
(30
m
No
a
' 1 + to
--- +
UL.
(3b)
T1
0
?t0+tt:
(3c)
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3 w
a ? (~ 1
dt2 plc) t?o To
d-2
dt
t=tiz:
No Or o T1
(3I)
where To 0 and Tl 't 0 . The equation (3s) is an equation
(2) for tho moment tm, The relation (3b) is find from the
condition d ( Id D
dt To tffitr,
(3d)
.. In (3c) 9 is
the time, measured from the beginning of SID to the moment
of N(t) maximum. The equations (3d) and (3d) and (3e) for
the moments t-0 and t-tr respectively are obtuincd PY
calculations of the second derivative3 of N(tyNo; their
meanin s .must be taken from experimental graph 11(tANo. Th;,,
value T6 can be found from solution :)f equations (3) ; the
course rith timo I(t)Io can be determined by this mcthod
of calcula-61-,.i 1-.; must be noted thrit the course ,?ith time of
N (t1o during SID dust be continuous and cuff iciently
smooth.
The course '.iith time of I(tYI0 for the flare 28/1"III-57,
is presented on fig.2 calculated by just dcceribcd method.
Variations of II(tV-To durini 'ID rere det3Ymincd by fmin; the
smoothed values of fmin v' ro used. It '"as found, that
4800 sc .J . and tr a 600 Sao.
Thus, taking into account the nonstationary process during
31:t) 1/s the method of determination fo value
1
Co
s X-570-
and course with tune of solar flares emission, active for
ionosphere is sugh:e: st-: d .
It seems possibly to apply this method to the determination
of an effective recombination coefficient using the dirunal
ohanges of critical frequencies for different ionospheric
l aye rs..
It *.'ould be also very interostin , to compare such
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? 4
analysis of SID rith the date on I.;-rr:y radiation of f1.,r..
obtained on the artifioial satellites of the -rth.
R L F L R I N C F S
1. J.Teubenhei1!1,
H ,A .Carom
B .A 4 P?..Ellison,
54 V. .!.Ferrero,
6. E.V.Applfton,
J.:.tr..Terr.Phys. ,vol,11 ,pie,1,1957,
14-22.
u3LBCT&L ; I;li':iC':'~n l ACTPOG)i?18,?iLIE CItO C oepaa-?
TOp.nz . T.19 .
TaJ ,ri.:,?:r i; yiimIdi; 3 1p:i , 1946 r . c ocxna ,
Solar ecllpsos and the ionosphere. 1956,
130-1f33.
Nature, vol. 175, No.4449, 1955,2 42-22:44.
J.itri.Terr.p11ye.,Vol.3,
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5 w
C .~,PTI ONS .
Fig. 1 comparison of the experimental and theoretical
curbee of the electron density variations during;
the flares.
Time - r7osooTc; T` e 4000 soe$
a) 1. Intensity variations I(t)/I0 of the flare in H
2. Variations N(t) exp determined by fmin
No
3. Theoretical variations Nit)
f th
b,o) 1. Variations of the emission flow. (t) /+o
of the flare in H,
2. Variations *jot exp determined by tv th
3. Thuorl~,,tical vnr.iations 3 t / th
No
Fig.2 Variations of electron production function I(t)/Io
during the flare 2e,/Vi.-L'1-57
1. Variations N t / exp- clctcrminod by f min
70
22 Smoothed curve Njt) / exp.
No
3. ~~pproxirnating triangular function t)
10
4. Variationu 1(t) /I0 computed by eq. (1)
rith To s 4800 sec.
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