Boris Komitov /selected abstracts of papers
and presentations (1997-2001)

SCHOVE`S SERIES, CENTURAL AND
SUPERCENTURAL VARIATIONS OF SOLAR
ACTIVITY. RELATIONSHIPS BETWEEN THE
MAXIMUMS OF 11 - YEARS ADJACENT CYCLES.


Boris Komitov

On the basis of indirect data for 3rd - 20th century - obtained over
the base of evaluations on the nine degree power scale of 11- year Schove`s
series cycles, time variations of solar activity has been investigated for
the above mantioned period of time. As a result
104 and 204 - year cycles of duration, as well as traces of cyclic
variations of 77,88,130 and 350 period of years have been established.A
comparison with the data of radiocarbon contents in ligneous sample has been
made, and it is evident that the main distinguishing feature,between
Schove`s series and C14 temporary time series,is the absence of
trend and cycles of duration of over 500 years in the data of the first sample
and their presence in the second one.The validity of the relationship
W2 > W1, has been checked,where W1 and W2 are respectively near maximum
Wolf`'s number values for the even and the odd cycles following them,
concerning the investigated period of time i.e.1700 years.On the
grounds of the aforesaid the probability for the breach of order in that inequality
i.e. the even cycles to be higher than the odd cycles following them, increasis
at high even cycles. The breach of order is a practically inevitable event
at the highest even cycles for which near maximum average annual Wolf 's
number values exceed 125 . On the basis of these results an assumtion
has been made that the forthcoming 23rd solar cycle will be weaker in power
than cycle No 22.

in BULG. GEOPHYS. JOURNAL 1997 v 23 No 1-2
 See also /in Bulgarian/ The Violation of Gnevishev -Ohl Rule...) and the next abstract

AMPLITUDE VARIATIONS OF THE 11 YEAR CYCLE
AND THE CURRENT SOLAR MAXIMUM 23


Boris Komitov
Institute of Astronomy, Bulgarian Academy of
Sciences, P.O. Box 179, 6000 Stara Zagora, Bulgaria;
komitov@mbox.digsys.bg
and
Boncho Bonev
Ritter Astrophysical Research Center, Department of
Physics and Astronomy, University of Toledo,
Toledo, OH 43606; bbonev@astro1.panet.utoledo.edu
Received 2000 August 29; accepted 2001 April 26;
published 2001 May 30

We examined the conditions for violations of the Gnevyshev-Ohl rule,
which states that the even-numbered
11 yr solar cycles have been followed by higher in amplitude odd-numbered
ones.This regularity has been valid for the last 150 years, but it is very
likely to be broken in the current 11 yr cycle 23. We used the Schove
series, which includes the main macrocharacteristics of the 11 yr cycles and
is continuous since the end of the third century. The reliability of these
data has been discussed. A total of 152 cycles were investigated,
the last onebeing cycle 21 in the International Sunspot Number series.
We showed that there is a well-outlined group of even-numbered 11 yr cycles
that are very likely to be followed by weaker odd-numbered ones. These are
the most powerful even cycles, characterized by maximum
monthly smoothed Wolf numbers exceeding 125 and decay times of 6 yr or
more. The main factor for violations of the Gnevyshev-Ohl rule is a very
high maximum of the even-numbered 11 yr cycle. Applied to the present
Hale cycle, which consists of 11 yr cycles 22 and
23, our analysis implies a high probability for violation of the Gnevyshev-Ohl
rule. The development of 11 yr cycle 23 confirms this conclusion. We
argue that the present 11 yr cycle should not be qualified as ÓabnormalÔ
when referring to the fact that it breaks a regularity that has lasted for
150 yr. The 11 yr cycle 23 might reveal a feature in the dynamics of the Hale cycle
that the strongest even-numbered 11 yr cycles are likely to be followed by
lower amplitude odd-numbered ones. We briefly discuss the relation
between the long-term solar variability and the current violation of the
Gnevyshev-Ohl rule
. The Astrophysical Journal, 554:L000–L000, 2001 June 10

See also Solar Activity Prediction Service

: NEW TWO-VARIABLE FITS FOR THE SCALE-
LENGHTS OF CN AND ITS PARENT
MOLECULE IN COMETARY ATMOSPHERES:
APPLICATION TO THE IDENTIFICATION OF
THE CN-PARENT


Bonev, B.; Komitov, B.

Affiliation:
AA(Bowling Green St. Univ./Univ. of Toledo),
AB(Inst. of Astronomy - Bulgarian Academy of Sciences)

We provide new two-variable fits describing the variability of the Haser
scale lengths of CN and its parent molecules. As in our previous reports
on this subject we use the heliocentric distance and the 10.7-cm solar
radio flux as independent variables. Such description reduces the error
bars and avoids the systematic behavior observed in the residuals of the
one-variable fits with only the heliocentric distance. The data for the
CN parent scale length include 56 reported values from different comets
over a period of two solar cycles. On that basis, using the connection
between true and Haser scale lengths, we discuss the possible CN parents
HCN and C2N2. These two molecules have been separately highlighted in
different papers as the most probable candidates for a major CN parent.
Our two-variable fit implies a brightness distribution of CN which may
be explained under the assumption that the C2N2 molecule is the single
CN parent.

Journal: American Astronomical Society, DPS
meeting #32, #41.05Publication
Date: 10/2000
Origin:AASAbstract Copyright
: (c) 2000: American Astronomical
Society Bibliographic Code:
2000DPS....32.4105B

CCD PHOTOMETRY OF COMET C/1999 S4 (LINEAR) at 387 nm: FIRST RESULTS


Komitov, B.; Bonev, B.; Bonev, T.; Ivanova, A.
Affiliation:
AA(Inst. of Astronomy - Bulgarian Academy of Sciences)
AB(Univ. of Toledo)
AD(Inst. of Astronomy - Bulgarian Academy of Sciences)

CCD observations on comet C/1999 S4 (LINEAR) were done on July 3 and
July 4, 2000 with the 2-meter telescope in the National Astronomical
Observatory "Rozhen", Bulgaria. We used a narrow-band filter centered at
387 nm. Brightness profiles of CN, which correspond to conditions close
to the current solar maximum, were obtained and analyzed with the Haser
and the vectorial exospheric models. The results are compared with obtained for
other comets.

Journal of American Astronomical Society, DPS meeting #33,
#41.21Publication Date:10/2000
Origin:AASAbstract Copyright:
(c) 2000: American Astronomical
SocietyBibliographic Code:
2000DPS....32.4121K

AMPLITUDE VARIATIONS OF CENTURIAL AND
BICENTURIAL SOLAR CYCLES


Boris Komitov
.
The subject of this report is to demonstrate the changes in the power
appearences of the centural and bicenturial solar cycles .
For this purpose two independent series indirect data on the base
of the solar actuvity have been used i.e. :1) Schove's series ,
containing continuous data for the last 1700 years . 2) radiocarbon
tree series for the last 4500 years. Cyclic changes at the amplitudes of the
two cycles have been established .The amplitude variations are
very big at the bicentural cycle ( T = 205 yrs. ). As a result , about 2300
- year powerful cycle of duration , has been established among them
and also a second one of about 1050 period of years which
is weaker than the first one . In this context, around the deep
minimums of the supercentural solar activity course , as for example
the period XV/ th - XVII/ th century ( between the Sprorer's
and Mounder's minimums ) the bicentural cycle completely dominates
over all the rest , which compete with its variations . In the epochs
which are removed , back or earlier in the time at about 1000 - 1200
years, compared with deep solar minimums the picture is
just the opposite . In connection with these facts the bicentural cycle
is very weak or is completely absent in this epochs . A very weak
dynamics showed also the powerful appearances of the centural cycle .
Their range of varability has an average period of about 1350 years.

 paper in 6th National Conferrence of Solar-Terrestrial Physics,Sofia,1999