Shorter Contributigns Pea~oMe

I I O [ I O H { E I I H f I 1 7 I A [ I E O M A I ' t l H T I I b I X IIO.~IOCOB HCCaE~OBAtIHBIE ~JI/t qEXOC~rIOBA~HHX FOPIIMX H O P O ~ ~ O H E M B P H 1 7 I C H O F O tl 1 - [ A J I E O 3 0 ~ f C [ ( O F O BO3PACTA (Ilpe~BaplTweJ1~uoe cooSmem~e) VkCLA.V BucIIA

FeogSu.~uuec~tt~ u~cmumym tI CAH, Hpaza [
.~[a(-x~ cpe;~Heii A,~,epnKn ~ npo:toaa~aeTca n IO-B rianpam~cInUt (~e.~t6pHfi) ,tepea mvm(yio A~pm~y, iI}1;I~m (op;xom~) ~i 14H.xoHe3~lm. 3;~eeI, oHa nonopaunBaeTea ~ ce~epy ~ r(pox o a u r uepea Pinoim~ }I BOCTOqttylo qac'rh Cr~6~prl (Nap6oH, riep~t~), l-laaeo,~mrm~Trl~e }Iec.ae.~oBamt~1, n tlaC.THOCTtI ~(e.~6p~fic~nx r~ op~oB}v~e(;N~x ropHh~X nopoa noxwr~ep~.~atoT ~[BI~H~eIIIIO iloo"lIoca rio KpttBofl OT 3orla2Ia K BOCTONytI erlOCO6eTnylOT 06'bflCHeIllilO O0:IMHOFO pa;r cylllecTBytoillero rToit.a eme B t,.mponh~x na.aeoMarrt~Tm,~x galiHiaX Me;n,~y nepHojLaHH /IoKe.~t6pH~I ~I ,~eBotla. I.I3 epamteHITn rlaneo~tarHtiTHhtx ;latiHhlX n EBpone a AMept.iiio 6r~ran cae.-mm,~Her-:OTOphIe~{omaeaar~,a}o*toHrrno RBrTme}rllrl o6(mx I{OIITIIHOHTOB. Hoc'rym~:ro 9. 12. 1960

S O M E T Y P E S OF G E O M A G N E T I C P U L S A T I O N S S T U D I E D AT T H E F A S T - R E C O R D I N G O B S E R V A T O R Y BUDKOV WITH AN INDUCTIVE MAGNETOMETER l~r ,r!ylf 1r KONESN~"

Geophysical Institute, Czechosl. Acad. Sci., Prague*) Oscillations of d i f f e r e n t frequencies are s u p e r p o s o d on long periodic c h a n g e s in t h e geomagzmtie field. Oscillations h a v i n g a period s h o r t e r t h a n a few h u n d r e d s e c o n d s w i t h a n a m p l i t u d e of the o r d e r of 10 -7 to 10 -~ Oe h a v e b e e n called p u l s a t i o n s . D u e to m u t u a l differences a n d the n u m b e r of years in w h i c h classification has n o t b e e n c!ear, t h e 10th Corrmfittee of I A G A called for t h e series of p u l s a t i o n s lasting several h o u r s a n d h a v i n g an a m p l i t u d e of t h e or(fer of 0.1 y to be k n o w n as Pc p u l s a t i o n s (Fig. 1) a n d t h o s e of l i m i t e d d u r a t i o n (usually s h o r t e r t h a n one hour), w i t h a n a m p l i t u d e of a few t e n t h s of y a n d o f t e n a c c o m p a n y i n g b a y - d i s t u r b a n c e s , as P t ' p u t s a t i o n s (Fig. 2). The stutty of b o t h Pc a n d Pt pulsation~ is s u b j e c t to suitable i n s t r u m e n t a l e q u i p m e n t . of t h e o b s e r v a t o r y . Due to the s h o r t p e r i o d . a n d small a m p l i t u d e of the p u l s a t i o n s s t a n d a r d v a r i o m e t e r s , the ser~sitivity of w h i c h rarely exceeds 1 y/ram, eanno~ always be success-

6/,13,,,

6 ~,24~,, Fig. i. 2. 4. 1959, 06 h 13 m - - 0 6 h 24n G. M. T. (Pc)

*) A d d r e s s : Bo6ni II, P r a h a 4 - - Spof'ilov. Studia geoph, et geod. S (1961)

073

]~ pam~:ue cooSutettun

fully used for t h e i r recording. T h e r e are m a n y m e a s u r i n g i n s t r u m e n t s w h i c h p e r m i t reliable recording of g e o m a g n e t i c p u l s a t i o n s . A c c o r d i n g to t h e i r c o n s t r u c t i o n t h e y m a y be divided i n t o two basic groups: i. a p p a r a t u s w i t h classieM m a g n e t o m e t e r s , w h e r e t h e mag-aet is s u s p e n d e d o n a fibre or b a l a n c e d o n a c u t t i n g edge, 2. a p p a r a t u s w h i c h t r a n s f o r m s c h a n g e s in t h e m a g n e t i c field to c h a n g e s in electric c u r r e n t . T h e m o s t f r e q u e n t l y used of t h e l a t t e r g r o u p is ~he i n d u c t i v e m a g n e t n m e t e r , w h i c h consists of a coil a n d g a l v a n o meter. T h e coil axis is o r i e n t e d i n t o t h e d i r e c t i o n of t h e g e o m a g n e t i c field e l e m e n t b e i n g m e a s u r e d . T h e f l u c t u a t i o n s in its i n t e n s i t y are caused b y c h a n g e s in t h e m a g n e t i c flux t h r o u g h t,h e s u r f a c e of t h e 20~9" 21~; coil, t h u s i n d u c i n g in t h e coil a n eros e = -- d e ~ d r . T h e c u r r e n t p r o p o r t i o n a l to Fig. 2. 5. II. 1959, 2 0 h 5 8 - 5 m - - 2 1 h 0 0 m t h e s e c h a n g e s t h e n flows t h r o u g h t h e G. M. T. (Pt) g a l v a n o m e t e r c o n n e c t e d t o its t e r m i nals. A n flnductive m a g n e t o m e t e r was b u i l t in 1958 in t h e G e o p h y s i c a l I n s t i t u t e of CAS for s t u d y i n g r a p i d t i m e c h a n g e s in t h e Z c o m p o n e n t ot t h e g e o m a g n e t i c f i e l d w i t h a sensit i v i t y of t h e order of 10 -2 y/see/ram; t h i s i n s t r u m e n t was p u t into p e r m a n e n t o p e r a t i o n a t t h e g e o m a g n e t i c o b s e r v a t o r y B u d k o v f r o m I. 1. 1959. T h e coil, d = 16 m in d i a m e t e r , is m a d e of a n i n s u l a t e d c o p p e r cable, a n d h a s 42 t u r n s a n d a t o t a l r e s i s t a n c e of 2 5 [ L I t is placed h o r i z o n t a l l y into a c i r c u l a r e x c a v a t i o n a t a n a v e r a g e dept.h o f 80 e m b e l o w t h e surface. T h e course of t h e t i m e c h a n g e s is r e e o r d e d o p t i c a l l y w i t h a g a l v a n o m e t e r o n pho~ographic p a p e r , w h i c h is m o v e d a t 15 m m / m i n . T h e r e c o r d i n g s p e e d w a s c h o s e n so t h a t t h e t a n g e n t to t h e inflection p o i n t of th~ curve, c o r r e s p o n d i n g to t h e course of t h e p u l s a t i o n s w i t h t h e m o s t f r e q u e n t l y o c c u r r i n g frequency*), enclosed a n a n g l e of a p p r o x i m a t e l y 120 ~ w i t h its successive axis. W h e n t h e deflections of t h e t a n g e n t f r o m t h i s a n g l e are large t h e r e c o r d e d p h e n o m e n is e i t h e r too d e n s e or e l o n g a t e d , in b o t h e a s e s t h e r e s u l t b e i n g i n d i s t i n e t . W i t h r e e o r d i n g e q u i p m e n t w h e r e t h e c y l i n d e r is s h i f t e d u n i f o r m l y in t h e d i r e c t i o n o[ t h e r o t a t i n g axis, a sufficient d i s t a n c e b e t w e e n t h e c u r v e s denot, ing t h e course m u s t be c h o s e n to p r e v e n t t h e i r o v e r l a p p i n g . L e t us n o w r e t u r n to t h e d i f f e r e n t t y p e s of p u l s a t i o n s r e c o r d e d w i t h a n i n d u c t i v e m a g n e t o m e t e r from I. 1. I959 to 30. 9. 1930 a t t h e Budkov observatory. Pc

TYPE

PULSATIONS

T h i s t y p e of p u l s a t i o n s is c h a r a c t e r i z e d b y its r e l a t i v e l y long d u r a t i o n ( s e v e r a l hours) w i t h t h e maximLun of o c c u r r e n c e in t h e d a y t i m e . A m o n g t h e s e regular p u l s a t i o n s we f o u n d , p a r t i c u l a r l y in t h e a f t e r n o o n , p u l s a t i o n s w i t h a p e r i o d u s u a l l y b e t w e e n 20 a n d 40 sec, w h i c h can be d i v i d e d into dist.inet g r o u p s . P u l s a t i o n s in t h o s e g r o u p s of w h i c h t h e

71/'23 "'

Fig. 3. 20. 7. 1959, 11 h 23 m - - l [

17 ~'28 "~'

h 28 m G. M. T. (P% beating pulsations)

p e r i o d is m o s t f r e q u e n t l y 4 - - 5 m i a . h a v e b e e n called b e a t i n g p u l s a t i o n s P % (Fig. 3). T h e i r c h a r a c t e r i s t i c f e a t u r e is t h e g r a d u a l increase in t h e a m p l i t u d e of t h e oscillat i o n s in t h e b e a t u p to a m a x i m u m , a f t e r w h i c h it g r a d u a l l y d e c r e a s e s again. T h e s e g r o u p s are r e p e a t e d in c e r t a i n t h n e i n t e r v a l s , o f t e n a f t e r a p e r i o d of s e v e r a l hours. *) A t B u d k o v observatory../--~ 0"03 -- 0-05 Hz. O7,~

Studia geoph, e t g e e d . 5 ~1961)

Shorter Contribution.~ Our a t t e n t i o n was a r r e s t e d b y a nm~nber of e~xceptions to this rule. Cases were f o t m d in w h i c h t h e a m p l i t u d e cIid n o t g r a d u a l l y increase to a rnaximtun; a f t e r t h e initial c o n s t a n t course w h i c h last, ed 1 -- 2 m i n u t e s , t h e r e was a r e l a t i v e l y a b r u p t increase to t h e m a x i m u m , a f t e r w h i c h t h e a m p l i t u d e g r a d u a l l y d e c r e a s e d (Fig. 4). A large a m o u n t of r e c o r d i n g m a t e r i a l was s u b j e c t e d to a careful analysis b u t o n l y a small n u m b e r of such p h e n o m e n a were f m m d so t h a t t,heir possible d e p e n d e n c e s canno~ y e t be s a t i s f a c t o r i l y d e t e r m i n e d . A n o t h e r interest.ing p h e n o m e n o n was f o u n d on t h e records e. g. of 6.9. 1959, 18.9. i959 or 21. 1. 1960. I t is seen f r o m t h e s e records t h a t t h e regular course of t h e _Pc p u l s a t i o n s

-

I

I

I

13~'23 Fig. 4. 16. 9. 1959, 13 h 19 m - - 13 h 23 m G. M. T. ( " h a l f - b e a t " p u l s a t i o n s )

tOh32"

7o~36 Fig. 5a. 6. 9. 1959, 10 h 32 m - - 10 h 36 m G. M. T. (superposirion)

t,,.//

,&

iTs'f6 ~

Fig. 5b. 21. 1. 1960, 11 h 16 m - - l l

h 19 m G. M. T. (superposition) v

0 7 ~' 7G "

Fig. 5e. 18. 9. 1960, 07 h 13 m - - 0 7 h 16 m G. M. T. (superposition) Studia geoph, et g e o d . 5 (1961)

275

l~ pam/z ue coodufettu.ct

is i n t e r r u p t e d in some i n t e r v a l s b y oscillations w h i c h in t h e i r a m p l i t u d e a n d p e r i o d do n o t b e l o n g to t h e basic course. T h e resul~an~ sl~ape of t h e c u r v e s i n d i c a t e s t h e s u p e r p o s i t i o n of h i g h e r h a r m o n i c s on t h e basic p u l s a t i o n f r e q u e n c y in t h e d i s t u r b e d i n t e r v a l (Figs. 5a, b, e). T h i s p h e n o m e n o n was r e c o r d e d e x c l u s i v e l y in t h e p e r i o d of i n c r e a s e d m a g n e t i c activity. Pt

TYPE

PULSATIONS

As was s t a t e d a b o v e , t h i s t y p e of p u l s a t i o n s differs from t h e P c p u l s a t i o n s b y its l i m i t e d d u r a t i o n , b y t h e m a x i m u m of occurrence, w h i c h is in t h e e v e n i n g , a n d l a s t b u t n o t l e a s t b y t h e course of t h e i n i t i a l a n d d e c a y i n g p h a s e . T h e i n i t i a l p h a s e is d i s t i n g u i s h e d in n e a r l y

20~o8" Fig. 6. 14. 1. 1960, 20 h 08 m - - 2 0 h 09.5 m G..'~. T. ( a c c o m p a n y i n g p u l s a t i o n s ) 'all eases b y a n e x p o n e n t i a l course a n d t h e d e c a y i n g p h a s e b y c o n s i d e r a b l e a t t e n , l a t i o n . G r o u p s of p u l s a t i o n s w i t h p e r i o d 2 - - 6 see a n d a m p l i t u d e f l u c t u a t i n g in f r a c t i o n s of T (Fig. 6) c a n be r e c o r d e d in t h e initial s t a g e of P t p u l s a t i o n (above a c e r t a i n i n t e n s i t y level, w h i c h is g i v e n b y t h e s e n s i t i v i t y of t h e i n s t r u m e n t s ) wi~h m e a s u r i n g e q u i p m e n t h a v i n g a h i g h s e n s i t i v i t y . T h e occurrence of s u c h p u l s a t i o n s is so f r e q u e n t l y t o g e t h e r w i t h t h e P t p u l s a t i o n s t h a t t h e y can be r e g a r d e d as p u l s a t i o n s a c c o m p a n y i n g P t t y p e s PULSATIO~N-S

"WITI-I

PERIOD

SHORTER

THAN

20

SEC

On 14. 7. a n d 18. 7. 1960 t h e B u d k o v o b s e r v a t o r y , u s i n g a s y s t e m h a v i n g s e n s i t i v i t y . of t h e o r d e r of 2 . 10 -a -(/see/ram, r e c o r d e d a n o t h e r t y p e of p u l s a t i o n s -- p e a r l s -- w h i c h are d i s t i n g u i s h e d b y s h a r p c h a n g e s in the field s t r e n g t h d u r i n g a s h o r t t i m e i n t e r v a l (Fig. 7, 8).

Fig. 7. 14.7. 1960, 01 h 33 m - - 0 1 h 34 m G. -~[. T. (pearls)

Fig. 8 . 1 8 . 7 . 1960, 0 l h 09 m - - 0 1 h 10 m G. M. T. (pearls) T h e series of s u c h p u l s a t i o n s last only a few hours. F r o m t h e p r e l i m i n a r y e l a b o r a t i o n it was possible to d e t e r m i n e t h e a p p r o x i m a t e l i m i t s of t h e f r e q u e n c y r e g i o n : 0 - 5 - - 2 e/scc, a n d it was also f o u n d t h a t t h e b r o a d r ~ e of a m p l i t u d e s in v a l u e s of 10 --a y f l u c t u a t e s a r o u n d t h e m i d d l e of t h e series. Ex~c~ v a l u e s will be de~ermined b y a d e t a i l e d analysis. R e c e i v e d 15. 11. 1960 276

Ret, iewer : ,Ft. B~hou,nek Studia genph, et geod. ~ (1961)

Shorter Contributions Pe3ioMe

t I E H O T O P b I E THI-IL[ FEOMAI'HHTI:[blX IINJIbCA[~HlYl, I-IPOC,,:IEH-~IIBAEMBIX IIPIJ I-IOM01I[H HII~NHII~HOItHOFO MAFHHTOMETPA B EbICTPOPEFIICTPI/IP,VIO[I~EIt O B C E P B A T O P H t l BV;~ HO B FeogSuau,r

uncmumym ~tC:IH, Hpaza

B pa6oTe paee.~taTpltBaeTcg tieciu)dli, No OCOOhtJ( r I'0OM,~IFII[HTIII,I'XIly.IhCalIIIfI aa',rplrpo~aauI, tx B nepp~ma OT 1. 1. 1959 r. 2o 30, 9. 1960 I'. tt o6cepnaTopi~l Fju r llyJii~CLlfItil~lTtIna .,De Ohl.'II~! O(~t[~lpyH~l.~tII,I, BO-llepBblX, lleOt~hItfHOC' gl~..-leHlle R TetietliIe pcr v m x p u o r o iipolteeca 6~e~mK nyzrm'~tpv~)mHx P% ~ nO-~Top~,~x - - IIet
~erm

lIocTyHg,'iO 15. 11. [960

?JBER

DIE VAglATIONEN DES IONOSPH~4RISCHEN CONVEgSIONSKOEFFIZIENTEN NACH S C H R 2 - ~ O E I N F A L L S M E S S U N G E N IM L A N G W E L L E N B E R E I C H H . , x s K o c h , Rt-DOLF SCm~tI.~DF.R Geop]~Iysilcalisches Observatorium Collm des Geoph. Ir~t. d. Karl-Marx.Universitiit, Leipzig*) I. E I N L E I T U N G A m G e o p h y s i k a l i s e h e n Observat, o r i u m Collm der I~2arl-3farx-Universlt~t Leipzig w e r d e n seit d e m 1. 10. 1957 regelm~Big SehrSgeinfallsme~sungem a u f 245 k H z (Sender K a l u n d borg) u n d 272 k H z (Semt.er (~eskoaloverisko) durehgeftihrt,. Die A u s w a h l d e r S e n d e r h a t t e f o l g e n d e Griinde: D a s O b s e r v a t o r i u m C o l h n v e r f S g t m i t d e n S t r e e k e n K a l u n d b o r g -Collm u n d ~eskosloven~sko-Collm fiber je ein*~ N o r d - u n d eine Sfidstreeke, so dal3 z o n a l e U n t e r s e h i e d o in d e n R e g i s t r i e r u n g e n erfaBt w e r d e n k 6 n n , m . Die glolehen S e n d e r w e r d e n s u c h a m O b s e r v a ~ o r i u m ffir Ionosphii, r e n f o r s e h u n g K f i h t t m g s b o r n u n d a m G e o p h y s i k a l i s e h e n Instit, u t d e r Tseheehosl. Akad. d. ~,Viss. in P r a g registriert, so dai3 ffir oine Z u s a m m e n a r b e i t bei d e r Boarbeitun~. oinzelner P r o b l e m e eine g u t e Vorausset, zung g e g e b e n ist. Die F r e q u e n z e n 245 kIffz u n d 272 k H z w e r d e n rail: S i e h o r h e i t a n d e r E - S e h l e h t (tagsfiber teilweise a n ebxer o b e r e n D - S e h i e h t ) reflekt~iert. Die M e s s u n g e n e r l a u b e n gleichzeitig eino guto E r f a s s u n g d o t D t ~ m p f u n g s e r s e h e i n u n g e n in d e r D - S e h i e h t . 2. P R I N Z I P

DER

MESSUNGEN

-

Die R e g i s t r i e r u n g des a b e n d l i e h e n u n d n f c h t l i c h e n R a u r n w e l l e n e i n f a l l s ( - - 5 ~ S o n n e n hShe bis Sendeschlu13) im L a n g w e i l e n b e r e i e h erfolgv n a e h d e r y o n S p r e n g e r [1] an~egeberten M e t h o d e u n t e r A u s b l e n d u n g der B o d e m v e l l e des gew/thlten S e n d e r s m i t Hilfe eines P e i l r a h m e n s . Die A u s p e i h m ~ erfolgt in den Mitt.agsstunden. d.a zu dieser Zeit die F e l d s t t i r k e d e r R a u m w e l l e infolge s t a r k e r D / ~ m p h m g in ([er D - S e h i e h t u n t e r der E m p f i n d liehkeics3chwelle des E m p f a n g e r s liegt. *) A n s e h r i f t : G e o p h y s i k a l i s e h e s O b s e r v a t o r i u m , Collm fiber Osctlatz, D D R . S t u d i a g e o p h , e t g e o d . 5 {196D

277