Using stochastic decomposition processes for formation spectra of oscillations
In work results of research of spread spectrum of superhigh-frequency oscillations in the polymodal resonator filled by plasma, placed in a magnetic field, due to stochastic disintegration of own modes of the resonator with participation of low-frequency plasma oscillations are presented. Experime...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2006
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| Series: | Вопросы атомной науки и техники |
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| Cite this: | Using stochastic decomposition processes for formation spectra of oscillations / A.N. Antonov, V.A. Buts, O.F. Kovpik, E.A. Kornilov, I.K. Kovalchuk, V.G. Svichenskij // Вопросы атомной науки и техники. — 2006. — № 6. — С. 178-180. — Бібліогр.: 3 назв. — англ. |
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irk-123456789-823012015-05-28T03:02:21Z Using stochastic decomposition processes for formation spectra of oscillations Antonov, A.N. Buts, V.A. Kovpik, O.F. Kornilov, E.A. Kovalchuk, I.K. Svichenskij, V.G. Plasma electronics In work results of research of spread spectrum of superhigh-frequency oscillations in the polymodal resonator filled by plasma, placed in a magnetic field, due to stochastic disintegration of own modes of the resonator with participation of low-frequency plasma oscillations are presented. Experiment is executed in conditions electron-cyclotron resonance for oscillations with frequency 2.77 GHz and powers up to 1 MW in plasma with density 109 cm -3 and electron temperature ~60 eV. The opportunity enlarge of a spectrum of oscillation formed by magnetron generator in hundred times is shown. Представлены результаты исследования уширения спектра сверхвысокочастотных колебаний в многомодовом резонаторе, заполненном плазмой, помещенных в магнитное поле, за счет стохастического распада собственных мод резонатора с участием низкочастотных плазменных колебаний. Эксперимент выполнен в условиях электронно-циклотронного резонанса для колебаний с частотой 2.77 ГГц мощностью до 1 MВт в плазме плотностью 109 см -3 при электронной температуре ~60 эВ. Показана возможность уширения в десятки раз спектра колебаний, формируемых магнетронным генератором. Представлено результати дослідження розширення спектру надвисокочастотних коливань в багатомодовому резонаторі заповненому плазмою, розміщених в магнітному полі, за рахунок стохастичного розпаду власних мод резонатора з участю низькочастотних плазмових коливань. Експеримент виконано в умовах електронно-циклотронного резонансу для коливань на частоті 2.77 ГГц з потужністю до 1 MВт в плазмі густиною 109 см -3 при електронній температурі ~60 eВ. Показана можливість розширення в десятки разів спектру коливань, що формуються магнетронним генератором. 2006 Article Using stochastic decomposition processes for formation spectra of oscillations / A.N. Antonov, V.A. Buts, O.F. Kovpik, E.A. Kornilov, I.K. Kovalchuk, V.G. Svichenskij // Вопросы атомной науки и техники. — 2006. — № 6. — С. 178-180. — Бібліогр.: 3 назв. — англ. 1562-6016 PACS:52.40. Mj http://dspace.nbuv.gov.ua/handle/123456789/82301 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Plasma electronics Plasma electronics |
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Plasma electronics Plasma electronics Antonov, A.N. Buts, V.A. Kovpik, O.F. Kornilov, E.A. Kovalchuk, I.K. Svichenskij, V.G. Using stochastic decomposition processes for formation spectra of oscillations Вопросы атомной науки и техники |
| description |
In work results of research of spread spectrum of superhigh-frequency oscillations in the polymodal resonator filled
by plasma, placed in a magnetic field, due to stochastic disintegration of own modes of the resonator with participation
of low-frequency plasma oscillations are presented. Experiment is executed in conditions electron-cyclotron resonance
for oscillations with frequency 2.77 GHz and powers up to 1 MW in plasma with density 109
cm
-3
and electron
temperature ~60 eV. The opportunity enlarge of a spectrum of oscillation formed by magnetron generator in hundred
times is shown. |
| format |
Article |
| author |
Antonov, A.N. Buts, V.A. Kovpik, O.F. Kornilov, E.A. Kovalchuk, I.K. Svichenskij, V.G. |
| author_facet |
Antonov, A.N. Buts, V.A. Kovpik, O.F. Kornilov, E.A. Kovalchuk, I.K. Svichenskij, V.G. |
| author_sort |
Antonov, A.N. |
| title |
Using stochastic decomposition processes for formation spectra of oscillations |
| title_short |
Using stochastic decomposition processes for formation spectra of oscillations |
| title_full |
Using stochastic decomposition processes for formation spectra of oscillations |
| title_fullStr |
Using stochastic decomposition processes for formation spectra of oscillations |
| title_full_unstemmed |
Using stochastic decomposition processes for formation spectra of oscillations |
| title_sort |
using stochastic decomposition processes for formation spectra of oscillations |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2006 |
| topic_facet |
Plasma electronics |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/82301 |
| citation_txt |
Using stochastic decomposition processes for formation spectra of oscillations / A.N. Antonov, V.A. Buts, O.F. Kovpik, E.A. Kornilov, I.K. Kovalchuk, V.G. Svichenskij // Вопросы атомной науки и техники. — 2006. — № 6. — С. 178-180. — Бібліогр.: 3 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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| first_indexed |
2025-07-06T08:48:39Z |
| last_indexed |
2025-07-06T08:48:39Z |
| _version_ |
1836886756465573888 |
| fulltext |
USING STOCHASTIC DECOMPOSITION PROCESSES FOR FORMATION
SPECTRA OF OSCILLATIONS
A.N. Antonov, V.A. Buts, O.F. Kovpik, E.A. Kornilov, I.K. Kovalchuk, V.G. Svichenskij
National Science Center “Institute of Physics and Technology”,
61108, Kharkov, Ukraine, e-mail: kovpik@kipt.kharkov.ua
In work results of research of spread spectrum of superhigh-frequency oscillations in the polymodal resonator filled
by plasma, placed in a magnetic field, due to stochastic disintegration of own modes of the resonator with participation
of low-frequency plasma oscillations are presented. Experiment is executed in conditions electron-cyclotron resonance
for oscillations with frequency 2.77 GHz and powers up to 1 MW in plasma with density 109 cm-3 and electron
temperature ~60 eV. The opportunity enlarge of a spectrum of oscillation formed by magnetron generator in hundred
times is shown.
PACS:52.40. Mj
1. INTRODUCTION
There are certain difficulties of creation of the
superhigh-frequency generators of the big level of power,
with adjustable width of a spectrum and spectral density
of power. It is caused by that, as a rule, generators
provide effective excitation of oscillations only at the
certain parameters of its operation, the deviation from
which leads to sharp deterioration of characteristics of
oscillations and their efficiency of excitation.
In work it is offered and investigated the formation of
spectra due to use of plasma nonlinear processes in
conditions of excitation the oscillations of the big
amplitude when stochastic disintegration processes take
place.
It was investigated increase the width of a spectrum of
the super-high-frequency (SHF) oscillations on frequency
2.77 GHz in the polymodal resonator with plasma in a
longitudinal magnetic field in conditions of an electron-
cyclotron resonance. Plasma was created by the beam-
plasma discharge. The density of plasma was
made 109 cm-3, with temperature ~60 eV. The level of
exited field in the resonator is more threshold value for
development of stochastic decay of a exited wave at
which nonlinear interaction of two microwaves of own
modes of the resonator and one own low-frequency (LF)
of a fashion of plasma takes place.
2. THEORETICAL ESTIMATIONS
Theoretical researches are put in a basis of statement
of experiment three-wave disintegration processes in
plasma. They are in detail enough stated in works [1, 3].
In them stochastic disintegration of the microwave on
high-frequency and low-frequency plasma (LF) is
considered.
As an example process of disintegration of a wave in
electrodynamics structure with tubular plasma can be
considered. In such plasma there are two superficial
waves. Frequencies of these waves of the order
2
pω
.
These waves are raised by electron beam. When the
amplitude of an exciting wave reaches some threshold
value, the mechanism of three-wave disintegration of this
wave on electromagnetic cross-section and lower hybrid
joins. To one of variants of three-wave interaction it is
presented on fig. 1.
Fig. 1. Dispersive curves of a tubular plasma wave guide
The system of the equations describing disintegration
process has a following appearance:
exp( )i
s
d
i i
d
ε
ε ρ τ
τ
= ∆ ,
exp( )s
i
d
i i
d
ε
ε ρ τ
τ
= − ∆ , (1)
2
2 *
2
exp( )i s
d i
d
ρ ρ ε ε τ
τ
+ Ω = − − ∆ ,
where iε – amplitude of a breaking up wave, iε –
amplitude of an electromagnetic wave, ρ – amplitude of
a low-frequency wave, Ω – dimensionless amplitude of a
low-frequency wave, ∆ – normalized difference of
frequencies of the waves. Transition to stochastic waves
is defined by factor [1]:
1
2
3 >
∆
=K (2)
that is carried out under condition of 2 1Ω > > .
Numerical modeling of system of the equations (1)
has confirmed that disintegration (decay) process begins
only at performance of a condition (2). At performance of
criterion (2), a spectrum of oscillations spreads, and
Lyapunov's exponents accepts positive values.
178 Problems of Atomic Science and Technology. 2006, № 6. Series: Plasma Physics (12), p. 178-180
Ω, χ
ω
k z
Ωh
ω
2
, κ
2
ω
1
, κ
1
2
pω
3. DESCRIPTION OF THE EXPERIMENTAL
SETUP
The experimental setup (fig. 2) consists of following
basic units: chambers of interaction - the polymodal
resonator (7) in a longitudinal magnetic field, the
magnetron generator (15), an electronic gun (2) in the
chamber (1, 5), probes of registration of oscillations in the
resonator (14), vacuum pumps (3, 6, 9), the solenoid (10),
a collector (12) in the chamber (11, 13), an electron beam
(8) and a data-acquisition equipment.
Fig. 2. The schematic image of the experimental setup
The chamber for creation of plasma is the cylindrical
copper resonator, with internal diameter 160 mm, long
650 mm. Face surfaces of the resonator are formed by
mobile plungers, with apertures in diameter 30 mm on an
axis, for posting through it of an electron beam in it.
Inside of the resonator pressure of gas (argon) was
adjusted from 5∙10-5 up to 10-3 mm Hg, for creation of
plasma of necessary density.
The resonator is excited on frequency 2.77 GHz by the
magnetron generator with power up to 1 MW. The
microwave power was brought by a rectangular wave
guide 72x34 mm., which was jointed with the resonator
on the average section on its length. As a result of
experimental researches optimum communication with
the resonator is picked up at orientation of a wave guide
for excitation on one frequency of simultaneously
necessary fashions in it. Wide walls of a wave guide were
guided along an axis of the resonator. Following own
modes of oscillations could be excited in the resonator
with the lowest indexes: H0 1 5, H2 1 7, H1 1 9, H2 1 8, H1 1 10,
H0 1 6, E1 1 5, E0 1 8, E0 1 9, E1 1 6. Identification of excited
modes of oscillations was spent by a method of a trial
body [2].
The electronic gun with termoemission cathode from
LaB in diameter 18 mm settled down on an axis of the
solenoid of a magnetic field. The accelerating voltage of a
gun changed from 0 up to -600 V a current 0-100 mA.
Simultaneously with measurements of frequency
characteristics of oscillations the registration accelerated
electrons in raised waves on brake x-ray radiation from
volume of the resonator was made. For this purpose the
system consisting of crystal NaJ and the photo multiplier
was used.
4. EXPERIMENTAL RESULTS
Studying of a spectrum of excited oscillations has
shown that the width of a spectrum of the SHF waves is
defined by their strange in the resonator. Prominent
feature of a spectrum is enlarge of it with displacement in
area of higher frequencies and presence of red and dark
blue satellites at frequency magnetron. Such spectrum is
characteristic for nonlinear disintegrations processes in
plasma. On fig. 3 the spectrum of excited oscillations is
presented for introduction of power of SHF oscillation in
the resonator ~1 MW.
Fig. 3. The microwave spectrum of oscillations in the
resonator.
Raised SHF oscillation test complex modulation on
frequencies 10…100 MHz. This modulation corresponds
to own plasma frequencies.
The spectrum of these low-frequency oscillations is
presented on fig. 4.
Fig. 4. A spectrum of low-frequency oscillations
On fig. 5 are resulted the oscillogramm of low-
frequency oscillations registered in the detected SHF
signal. Excitation of low-frequency oscillations has
threshold character, and their amplitude depends from
intense the microwave oscillations in the resonator. The
oscillogramm of intensity of x-ray radiation from volume
the resonator caused by braking accelerated electrons in
field exited waves is present on fig. 5 too.
179
Fig. 5. Oscillograms of low-frequency oscillations (top)
and x-ray radiation (bottom)
5. CONCLUSIONS
It is necessary to consider as the main-core result of
the executed experimental researches an illustration of an
opportunity of adjustment of width of a spectrum and
distribution of spectral density of oscillation power due to
use of nonlinear interaction of waves in plasma.
Qualitatively observable effects in experiment
coincide with theoretical representations in the description
of stochastic instability at nonlinear interaction of type a
wave-wave [1-3]. For it occurrence in a spectrum of SHF
oscillation of satellites and excitation with growth of their
capacity of the low-frequency plasma oscillations causing
complex character of modulation of high-frequency
oscillations is characteristic.
Authors express profound gratitude to M.G. Sokolov
for manufacturing of details, assembly, adjustment and
operation of experimental installation.
REFERENCES
1. V.A. Buts, I.K. Kovalchuk, E.A. Kornilov,
D.V. Tarasov. Stabilization beam instability as a
result of development of local instability at
interaction of type a wave-wave. // Plasma Physics.
2006, v. 32, №6, p. 1–10.
2. A.N. Antonov, V.A. Buts, O.F. Kovpik,
E.A. Kornilov, O.V. Manujlenko, V.G. Svichenskij,
K.N. Stepanov, J.U. Turkin. A stochastic heating of
plasma at an electronic cyclotron resonance // Letters
in JETF. 1999, v. 69, №11.
3. V.A. Buts, O.V. Manujlenko, K.N. Stepanov,
A.P. Tolstoluzhskij // Plasma Physics. 1994, v. 20,
p. 794.
ИСПОЛЬЗОВАНИЕ СТОХАСТИЧЕСКИХ РАСПАДНЫХ ПРОЦЕССОВ
ДЛЯ ФОРМИРОВАНИЯ СПЕКТРОВ КОЛЕБАНИЙ
А.Н. Антонов, В.A. Буц, О.Ф. Ковпик, Е.А. Корнилов, И.К. Ковальчук, В.Г. Свиченский
Представлены результаты исследования уширения спектра сверхвысокочастотных колебаний в
многомодовом резонаторе, заполненном плазмой, помещенных в магнитное поле, за счет стохастического
распада собственных мод резонатора с участием низкочастотных плазменных колебаний. Эксперимент
выполнен в условиях электронно-циклотронного резонанса для колебаний с частотой 2.77 ГГц мощностью до
1 MВт в плазме плотностью 109 см-3 при электронной температуре ~60 эВ. Показана возможность уширения в
десятки раз спектра колебаний, формируемых магнетронным генератором.
ВИКОРИСТАННЯ СТОХАСТИЧНИХ РОЗПАДНИХ ПРОЦЕСІВ
ДЛЯ ФОРМУВАННЯ СПЕКТРІВ КОЛИВАНЬ
О.М. Антонов, В.О. Буц, О.Ф. Ковпік, Є.О. Корнілов, І.К. Ковальчук, В.Г. Свіченський
Представлено результати дослідження розширення спектру надвисокочастотних коливань в
багатомодовому резонаторі заповненому плазмою, розміщених в магнітному полі, за рахунок стохастичного
розпаду власних мод резонатора з участю низькочастотних плазмових коливань. Експеримент виконано в
умовах електронно-циклотронного резонансу для коливань на частоті 2.77 ГГц з потужністю до 1 MВт в плазмі
густиною 109 см-3 при електронній температурі ~60 eВ. Показана можливість розширення в десятки разів
спектру коливань, що формуються магнетронним генератором.
180
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