Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave

Plane monochromatic electromagnetic wave scattering by charged particles is investigated theoretically taking into account the influence of scattered incoherent electromagnetic radiation on particles motion. The spread in the particles-velocity due to interaction of particles with each other via the...

Повний опис

Збережено в:
Бібліографічні деталі
Дата:2007
Автор: Ognivenko, V.V.
Формат: Стаття
Мова:English
Опубліковано: Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2007
Назва видання:Вопросы атомной науки и техники
Теми:
Онлайн доступ:http://dspace.nbuv.gov.ua/handle/123456789/110524
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Цитувати:Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave / V.V. Ognivenko // Вопросы атомной науки и техники. — 2007. — № 1. — С. 130-132. — Бібліогр.: 7 назв. — англ.

Репозитарії

Digital Library of Periodicals of National Academy of Sciences of Ukraine
id irk-123456789-110524
record_format dspace
spelling irk-123456789-1105242017-01-05T03:03:33Z Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave Ognivenko, V.V. Plasma electronics Plane monochromatic electromagnetic wave scattering by charged particles is investigated theoretically taking into account the influence of scattered incoherent electromagnetic radiation on particles motion. The spread in the particles-velocity due to interaction of particles with each other via the fields of spontaneous incoherent radiation is shown to appear in the process of scattering of incident wave. Теоретично досліджено розсіяння плоскої монохроматичної електромагнітної хвилі зарядженими частинками з урахуванням впливу розсіяного некогерентного електромагнітного випромінювання на рух частинок. Показано, що в процесі розсіяння падаючої хвилі з'являється розкид по імпульсах частинок, обумовлений їх взаємодією одна з другою через поля спонтанного некогерентного випромінювання. Теоретически исследовано рассеяние плоской монохроматической электромагнитной волны заряженными частицами с учетом влияния рассеянного некогерентного электромагнитного излучения на движение частиц. Показано, что в процессе рассеяния падающей волны появляется разброс по импульсам частиц, обусловленный их взаимодействием друг с другом через поля спонтанного некогерентного излучения. 2007 Article Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave / V.V. Ognivenko // Вопросы атомной науки и техники. — 2007. — № 1. — С. 130-132. — Бібліогр.: 7 назв. — англ. 1562-6016 PACS: 52.25.Gj; 52.50.Jm; 52.59.Rz; 41.60.Cr http://dspace.nbuv.gov.ua/handle/123456789/110524 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
topic Plasma electronics
Plasma electronics
spellingShingle Plasma electronics
Plasma electronics
Ognivenko, V.V.
Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
Вопросы атомной науки и техники
description Plane monochromatic electromagnetic wave scattering by charged particles is investigated theoretically taking into account the influence of scattered incoherent electromagnetic radiation on particles motion. The spread in the particles-velocity due to interaction of particles with each other via the fields of spontaneous incoherent radiation is shown to appear in the process of scattering of incident wave.
format Article
author Ognivenko, V.V.
author_facet Ognivenko, V.V.
author_sort Ognivenko, V.V.
title Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
title_short Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
title_full Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
title_fullStr Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
title_full_unstemmed Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave
title_sort heating of charged particles at thomson scattering of a monochromatic electromagnetic wave
publisher Національний науковий центр «Харківський фізико-технічний інститут» НАН України
publishDate 2007
topic_facet Plasma electronics
url http://dspace.nbuv.gov.ua/handle/123456789/110524
citation_txt Heating of charged particles at Thomson scattering of a monochromatic electromagnetic wave / V.V. Ognivenko // Вопросы атомной науки и техники. — 2007. — № 1. — С. 130-132. — Бібліогр.: 7 назв. — англ.
series Вопросы атомной науки и техники
work_keys_str_mv AT ognivenkovv heatingofchargedparticlesatthomsonscatteringofamonochromaticelectromagneticwave
first_indexed 2025-07-08T00:42:14Z
last_indexed 2025-07-08T00:42:14Z
_version_ 1837037345918943232
fulltext 130 Problems of Atomic Science and Technology. 2007, 1. Series: Plasma Physics (13), p. 130-132 HEATING OF CHARGED PARTICLES AT THOMSON SCATTERING OF A MONOCHROMATIC ELECTROMAGNETIC WAVE V.V. Ognivenko NSC “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine, e-mail: ognivenko@kipt.kharkov.ua Plane monochromatic electromagnetic wave scattering by charged particles is investigated theoretically taking into account the influence of scattered incoherent electromagnetic radiation on particles motion. The spread in the particles- velocity due to interaction of particles with each other via the fields of spontaneous incoherent radiation is shown to appear in the process of scattering of incident wave. PACS: 52.25.Gj; 52.50.Jm; 52.59.Rz; 41.60.Cr 1. INTRODUCTION Investigation of processes of electromagnetic waves interaction with charged particles is of considerable interest for many applications of plasma physics and charged particles beams, such as heating of plasma by the external fields [1], stability of plasma in the external electromagnetic fields [2], its diagnostics [3], accelerations of electrons in the fields of laser radiation [4], increase of frequency in plasma [5]. The scattering of external electromagnetic waves by the charged particles is also concerned with generation of narrow-band ultrashort wavelength radiation at motion of relativistic electron beams in the external periodic fields [6]. The peculiar significance for these applications has finding out effects of radiation reaction on particles motion. In the given paper the results of theoretical research of the plane monochromatic electromagnetic wave Thomson scattering process by charged particles taking into account the influence of scattering radiation on particles motion are presented, the incoherent scattering of external wave by the charged particles being discussed. The charged particles motion in the total electromagnetic field in the limit case of a small value of unit-less wave strength parameter is considered. The spread in particles momentum is shown to appears in the process of incident wave scattering. The dependences of a mean-square value of particles longitudinal velocity on time are found and investigated by analytically and numeral methods. 2. FORMULATION OF THE PROBLEM Let us consider the ensemble of the identical charged particles with the charge of q, mass of m and homogeneous average density n0, moving in a field of a plane monochromatic electromagnetic wave (EMW) ( ) ( )krEE −= text ωcos0 , (1) where E0 is the amplitude of the wave electric field; ω, k are its frequency and wave vector. Assume that the E0 and k vectors are directed along axes 0X and 0Z accordingly Cartesian coordinates. Let us find the spread in the longitudinal velocity of particles, due to the interaction of particles via electromagnetic fields, produced by these particles at motion in the external field (1). Let us call the direction parallel to that of scattered wave propagation a longitudinal one (viz. along the OZ axis). In order to find solution in explicit analytical form let us consider ωmceEa 0= parameter as a small one which characterises a relative size of transverse oscillatory velocity of particle in the external field. Solution of a problem will be searched by the following method: let us consider the ensemble of charges as large number of the individual charged particles. Having found the field produced by the individual charged particle, moving in the external field, in the limit case of a small value of a parameter let us find the total longitudinal force, acting on the individual (test) particle, the mean-square longitudinal velocity being expressed via the ensemble average of the product of pair interaction forces of particles. 3. RESULTS AND DISCUSSION In the external field the charged particles oscillate in the direction parallel to the E0 vector. The equations for coordinate and velocity of particles can be written as follows: ( ) ( ) ( ) ( )tkztcat izxii ∆+−−= eerr ωω cos0 , ( ) ( ) zzxi kztcat vsin eev +−= ω , where { }iiioi zyx 000 ,,=r is the coordinate of i-th particle in the initial moment of time t0 (let t0=0), ( ) ( )tztz iii ∆+= 0 be the longitudinal displacement of particle trajectory relative to the initial position. Let us express electric and magnetic fields produced by the individual particle via Lienard-Wiechert potentials [7]. In the nonrelativistically motion of particles and small a value the expression for the electric field, produced by the i-th particle in r coordinate in t time is: ( )                   −−−     +      −−= ϕ ϕ cos3111 sin31, 2 2 2222 2 2 3 i xi ii ii x i x i i i R R RkRk kRR R R kaq R qt eRrE , (2) where ( ) ( ) ( )[ ]tzzyyxx iziyixi ′−+−+−= eeeR 00 , ( )[ ]tzRkt ii −−= ωϕ . A total field in the observation point of r in the time t will be determined by charges initial coordinates of which satisfy condition: sct 0rr −> (3) Let us consider the motion of some individual (test) particle both in the field (1) and in the fields, produced by mailto:ognivenko@kipt.kharkov.ua 131 all other particles. Equations of longitudinal motion of such particle (let it be the i-th particle) in these fields can be written as follows: ( )[ ] ( ) ( )[ ]∑== s si s ziz zi xttFtt dt d ;,,F p rr , (4) ( ) ( ) ( ) ( )[ ]       += zszss s z t c tEextF ,1,;, rHvrr , (5) where ri , pi are the position and momentum of the i-th particle at time t; ( ) ( )tt ss ,,, rHrE are the strength of electric and magnetic fields, produced by the s-th particle at time t in r coordinate. Let’s the considered system consists of N charged particles the coordinate and momentum of which at the initial time are random values. We introduce the distribution function of system states DN(x01,…, x0N; t0) at time t0. This function is normalized as: ∫DN(x01,…, x0N; t0)dx01…dx0N=1, where x={r, p}, x0s=xs(0). By integrating of Eq. (4) we can obtain the deviation of longitudinal momentum from the mean value for test particle ( )[ ]∫ ′′′=∆ t izzi tdttFp 0 ,rδ , (6) and expression for rate of change of mean-square spread in the longitudinal momentum of particles ( ) ( )[ ] ( )[ ]∫ ′′′=∆ t izizzi tdttFttFp dt d 0 2 ,,2 rr δδ , (7) where ∆pzi=pzi-<pzi>, zzz FFF −=δ , angular brackets indicate average values, ( ) ( ) ( )[ ] ( )∫= 0010 1 ;;,, dxxfxtxtt rFrF , ( ) ( )∫= NNN dxdxtxxxDNxf 0020002001 ...;...,, , f1 is the single-particle distribution function. The right-hand side of Eq. (7) is founded in neglecting of influence of fields, produced by particles on its motion. Thus in the right-hand side of Eq. (7) ri (t) can be replaced by unperturbed trajectory ( )( ) ( )0;0 =∆= tt ii rr of particle in the external field (1). Taking into account that particles are identical and neglecting initial correlation between them Eq. (7) can be expressed as ( ) ( ) ( ) ( ) ( ) ( )[ ] ( ) ( ) ( ) ( )[ ]ossi s zossi s z t V ososzi xtxtFxtxtF xfdxtdp dt d ,;,; 2 00 0 1 2 ′′× ×′=∆ ∫ ∫∫ ′ ξξ , (8) where ( )( ) ( )( ){ }ttrt ii ,00 =ξ Analytical expression for the force, acting on an individual particle in the electromagnetic field, produced by the other particle will be derived by substituting expression for field (2) in Eq. (5): GkqFzs 22= ,               ρ ψ +ψ− ρρ ρ = ttt z aG cossin1 2 02 , (9) where zt ρρψ −= , ( ) 2122 zt ρρρ += ⊥ , ( )siz zzk −=ρ , ( ) ( )2 00 2 00 sisi yyxxk −+−=⊥ρ , 20 aa = . Neglecting initial momentum spread the Eq. (8) for rate of change of root mean square longitudinal particles momentum is: ( ) ( ) ( )[ ] ( ) ∫∫ ⊥′=∆ 'V 0 2 0 4 0 2 0 ,4 t sszi dGtdqknp dt d rρρπ τ , (10) where V0 is the integration region determined by condition (3). Having integrated Eq. (10) taking into account the fact that particles are at some finite distance one from other, we find: ( ) 222 QRz σσβ +=∆ , (11) where ( ) ttNa r R ωω λ σ 212 0 0 3 = , tNr Q ω λ π σ 320 33 = , 3 0λnN = , 22 0 mcqr = , cv zz =β . As a minimum distance between particles the value of 31 0min −= nr was taken. The first term in right hand side Eq. (11), that depends on parameter a, is the longitudinal particle velocity spread, due to interaction of particles via the electromagnetic waves. The second term in Eq. (11), that is not dependent on parameter a, describes the spread, due to the coulomb interaction of particles. On the ( )4231 KNt π>>ω times the particle velocity spread will be determined by interaction of particles with each other via electromagnetic waves. The expression for the momentum spread in this case may be presented as follows: ( )[ ] ( )( ) ( )tt eff R z N 2 0 1212 ε ε β ∆ =∆ , (12) where 22πωtNNeff = , ( ) 32 2 0 21 tkaqR ωε =∆ is the energy losses of an individual charge on radiation, 2 0 mc=ε . Now let us consider the EMW scattering on the clusters of the charged particles, having a form of a circular cylinder with the height of lb and radius of rb. Let the wave vector k be parallel to the axis of a cylinder (cluster). The spread in the longitudinal particle velocity will be described by Eq. (11) for particles present in the initial moment of time in the center of cluster on the cylinder axis and at the distance of lb/2 from its base. Thus the first term in this equation, corresponding to the radiative interaction, is: 21 2 0 0)( 2 2               Φ λ π τ λ =σ=σ b bbc RR l rl Na r , (13) where Φ(x)=x arcctg(x). When Eq. (13) was derived a considered test particle was assumed to be located in the influence region of fields of all other particles of the cluster. Eq. (13) shows, that for the sufficiently wide charged particles cluster (2rb>>lb) longitudinal velocity spread due to the radiative interaction of particles will be proportional to the root square from the number of particles in the effective volume bl 2 effV πλ= . The dynamics of the change of particles longitudinal velocity spread was investigated by particle simulation of the EMW scattering process on the charged particles cluster. The cluster has the form of a cylinder, whose axis coincides with the direction of external wave propagation. The radius of a cluster is equal to 5λ, and its length equals 10λ. A cluster consists of 5000 particles, a0=0.7, 132 λ=10µm. The motion of particles was described by equations (4), (5), (9). The dependence on the dimensionless time τ=ωtρ normalized value of the spread in the longitudinal velocity of N1 particles, located in the center of a cluster at the initial time t=0, is shown in the figure, where ( ) λπρ /32 21 00 Nlra b= . Namely the initial coordinates of these particles (test particles) were in the region, limited by the surface of a cylinder with the radius of r1=0.15rb and the height of l1=0.4lb . Axes of cylinders and planes of symmetry (a plane perpendicular to the axis of a cylinder and dividing its in two) coincide. 0 5 1 0 1 5 2 0 2 5 0 ,0 0 ,2 0 ,4 0 ,6 0 ,8 σ z /ρ 1 2 τ In this figure the curve 1 corresponds to the particle simulation, and curve 2 - the dependence of the longitudinal velocity spread, determined by Eq. (11), (13). Here ( )222 zzz β−β=σ , ∑ = = 1 11 1A N i iA N - summation is carried on over all test particles, N1 is their total number. The figure shows that the spread in velocity is proportional to the t on the initial stage of scattering. The results of numeral simulation agree with the analytical estimations by Eqs. (11), (13). On the times τ>5 the rate of change in longitudinal velocity spread decreases. Thus, the EMW scattering on the charged particles leads to the increase of the velocity spread of particles. REFERENCES 1. K.N. Stepanov. Nelinejnye javlenija pri ionnom ciklotronnon rezonanse v plazme // Fiz. Plazmy. 1983, v. 9, 1, p. 45 - 61 (in Russian). 2. V.P. Silin. Parametricheskoe vozdejstvie izlychenija bjl’shoj moshchnosti na plazmu. M.: “Nauka”, 1973. (in Russian.). 3. H.J. Kunze. Plasma Diagnostics/ Ed. by Lochte- Holtgreven. W. Amsterdam: “N-H Publ. Co.” 1968. 4. V.V. Appoloniov, Yu.A. Kalachov, .F Prohorov et al. Uskorenie elektronov pri vynuzhdennom komptonovskom rassejanii // Pis’ma v ZhETF. 1986, v.44, 2, p.61-63. (in Russsian.) 5. Ya.B. Fainberg. Plasma electronics and plasma methods of charged particle acceleration // Plasma physics reports. 1994, v.20, 7, p. 549-554. 6. V.I. Kurilko, V.V. Ognivenko. Scattering of electromagnetic wave by charged particle clasters // Plasma physics reports. 1994, v.20, 5, p. 426-432. 7. L.D. Landau, E.M. Lifshic. Theorija polja. M: “Nauka”, 1967 (in Russian). . . , , . . . , , .