Quantum electrodynamics in the strong pulsed laser fields
The some results on the resonant processes of quantum electrodynamics (QED) proceeding in the strong pulsed light fields, realized in modern powerful pulsed lasers is presented. The appearance of resonances in a laser field is one of the fundamental problems of QED in electromagnetic fields. Followi...
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Roshchupkin, S.P. 2017-01-15T12:32:06Z 2017-01-15T12:32:06Z 2013 Quantum electrodynamics in the strong pulsed laser fields / S.P. Roshchupkin // Вопросы атомной науки и техники. — 2013. — № 3. — С. 48-52. — Бібліогр.: 5 назв. — англ. 1562-6016 PACS: 034.50.Rk, 12.20.-m https://nasplib.isofts.kiev.ua/handle/123456789/111866 The some results on the resonant processes of quantum electrodynamics (QED) proceeding in the strong pulsed light fields, realized in modern powerful pulsed lasers is presented. The appearance of resonances in a laser field is one of the fundamental problems of QED in electromagnetic fields. Following QED processes of the second order in the fine structure constant in the pulsed laser field are considered: resonant spontaneous bremsstrahlung by an electron scattered by a nucleus, resonant photocreation of electron{positron pairs on a nucleus, and resonant scattering of a lepton by a lepton. The resonant peak's altitude and width are defined by the external pulsed wave properties. It is demonstrated that the resonant cross sections may be several orders of magnitude greater than the corresponding cross sections in the absence of an external field. Results obtained may be experimentally verified, for example, by the scientific facilities at the SLAC National Accelerator Laboratory and FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany). Розглядаються деякi резонанснi процеси квантової електродинамiки (КЕД), що протiкають у сильних iмпульсних свiтлових полях, реалiзованих у сучасних потужних iмпульсних лазерах. Поява резонансiв у лазерному полi є однiєю з фундаментальних проблем КЕД в електромагнiтних полях. Розглядаються наступнi процеси КЕД другого порядку зi сталої тонкої структури в iмпульсному лазерному полi: резонансне спонтанне гальмове випромiнювання електрона, розсiянного на ядрi; резонансне фотона-родження електрон-позитронних пар на ядрi й резонансне розсiювання лептона на лептонi. Амплiтуда й ширина резонансних пiкiв визначаються параметрами зовнiшньої iмпульсної хвилi. Показано, що резонанснi поперечнi перерiзи можуть надекiлька порядкiв величини бути бiльше, нiж вiдповiднi поперечнi перерiзи у вiдсутностi зовнiшнього поля. Отриманi результати можуть бути експериментально перевiренi в наукових об’єднаннях, таких як SLAC (National Accelerator Laboratory) i FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany). Рассматриваются некоторые резонансные процессы квантовой электродинамики (КЭД), протекающие в сильных импульсных световых полях, реализуемых в современных мощных импульсных лазерах. Появление резонансов в лазерном поле является одной из фундаментальных проблем КЭД в электро-магнитных полях. Рассматриваются следующие процессы КЭД второго порядка по постоянной тонкой структуры в импульсном лазерном поле: резонансное спонтанное тормозное излучение электрона, рассеянного на ядре; резонансное фоторождение электрон-позитронных пар на ядре и резонансное рассеяние лептона на лептоне. Амплитуда и ширина резонансных пиков определяются параметрами внешней импульсной волны. Показано,что резонансные поперечные сечения могут быть на несколько порядков величины больше,чем соответствующие поперечные сечения в отсутствие внешнего поля. Полученные результаты могут быть экспериментально проверены в научных коллоборациях, таких как SLAC(National Accelerator Laboratory) и FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany). en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Квантово-полевые и групповые подходы теоретической физики. Семинар памяти Петра Ивановича Фомина Quantum electrodynamics in the strong pulsed laser fields Квантова електродинамiка в сильних iмпульсних лазерних полях Квантовая электродинамика в сильных импульсных лазерных полях Article published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Quantum electrodynamics in the strong pulsed laser fields |
| spellingShingle |
Quantum electrodynamics in the strong pulsed laser fields Roshchupkin, S.P. Квантово-полевые и групповые подходы теоретической физики. Семинар памяти Петра Ивановича Фомина |
| title_short |
Quantum electrodynamics in the strong pulsed laser fields |
| title_full |
Quantum electrodynamics in the strong pulsed laser fields |
| title_fullStr |
Quantum electrodynamics in the strong pulsed laser fields |
| title_full_unstemmed |
Quantum electrodynamics in the strong pulsed laser fields |
| title_sort |
quantum electrodynamics in the strong pulsed laser fields |
| author |
Roshchupkin, S.P. |
| author_facet |
Roshchupkin, S.P. |
| topic |
Квантово-полевые и групповые подходы теоретической физики. Семинар памяти Петра Ивановича Фомина |
| topic_facet |
Квантово-полевые и групповые подходы теоретической физики. Семинар памяти Петра Ивановича Фомина |
| publishDate |
2013 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Квантова електродинамiка в сильних iмпульсних лазерних полях Квантовая электродинамика в сильных импульсных лазерных полях |
| description |
The some results on the resonant processes of quantum electrodynamics (QED) proceeding in the strong pulsed light fields, realized in modern powerful pulsed lasers is presented. The appearance of resonances in a laser field is one of the fundamental problems of QED in electromagnetic fields. Following QED processes of the second order in the fine structure constant in the pulsed laser field are considered: resonant spontaneous bremsstrahlung by an electron scattered by a nucleus, resonant photocreation of electron{positron pairs on a nucleus, and resonant scattering of a lepton by a lepton. The resonant peak's altitude and width are defined by the external pulsed wave properties. It is demonstrated that the resonant cross sections may be several orders of magnitude greater than the corresponding cross sections in the absence of an external field. Results obtained may be experimentally verified, for example, by the scientific facilities at the SLAC National Accelerator Laboratory and FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany).
Розглядаються деякi резонанснi процеси квантової електродинамiки (КЕД), що протiкають у сильних iмпульсних свiтлових полях, реалiзованих у сучасних потужних iмпульсних лазерах. Поява резонансiв у лазерному полi є однiєю з фундаментальних проблем КЕД в електромагнiтних полях. Розглядаються наступнi процеси КЕД другого порядку зi сталої тонкої структури в iмпульсному лазерному полi: резонансне спонтанне гальмове випромiнювання електрона, розсiянного на ядрi; резонансне фотона-родження електрон-позитронних пар на ядрi й резонансне розсiювання лептона на лептонi. Амплiтуда й ширина резонансних пiкiв визначаються параметрами зовнiшньої iмпульсної хвилi. Показано, що резонанснi поперечнi перерiзи можуть надекiлька порядкiв величини бути бiльше, нiж вiдповiднi поперечнi перерiзи у вiдсутностi зовнiшнього поля. Отриманi результати можуть бути експериментально перевiренi в наукових об’єднаннях, таких як SLAC (National Accelerator Laboratory) i FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany).
Рассматриваются некоторые резонансные процессы квантовой электродинамики (КЭД), протекающие в сильных импульсных световых полях, реализуемых в современных мощных импульсных лазерах. Появление резонансов в лазерном поле является одной из фундаментальных проблем КЭД в электро-магнитных полях. Рассматриваются следующие процессы КЭД второго порядка по постоянной тонкой структуры в импульсном лазерном поле: резонансное спонтанное тормозное излучение электрона, рассеянного на ядре; резонансное фоторождение электрон-позитронных пар на ядре и резонансное рассеяние лептона на лептоне. Амплитуда и ширина резонансных пиков определяются параметрами внешней импульсной волны. Показано,что резонансные поперечные сечения могут быть на несколько порядков величины больше,чем соответствующие поперечные сечения в отсутствие внешнего поля. Полученные результаты могут быть экспериментально проверены в научных коллоборациях, таких как SLAC(National Accelerator Laboratory) и FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany).
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/111866 |
| citation_txt |
Quantum electrodynamics in the strong pulsed laser fields / S.P. Roshchupkin // Вопросы атомной науки и техники. — 2013. — № 3. — С. 48-52. — Бібліогр.: 5 назв. — англ. |
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2025-11-25T22:43:10Z |
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2025-11-25T22:43:10Z |
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| fulltext |
QUANTUM ELECTRODYNAMICS IN THE STRONG
PULSED LASER FIELDS
S.P. Roshchupkin∗
Institute of Applied Physics NAS of Ukraine, 40000, Sumy, Ukraine
(Received September 10, 2012)
The some results on the resonant processes of quantum electrodynamics (QED) proceeding in the strong pulsed light
fields, realized in modern powerful pulsed lasers is presented. The appearance of resonances in a laser field is one
of the fundamental problems of QED in electromagnetic fields. Following QED processes of the second order in the
fine structure constant in the pulsed laser field are considered: resonant spontaneous bremsstrahlung by an electron
scattered by a nucleus, resonant photocreation of electron–positron pairs on a nucleus, and resonant scattering of a
lepton by a lepton. The resonant peak’s altitude and width are defined by the external pulsed wave properties. It
is demonstrated that the resonant cross sections may be several orders of magnitude greater than the corresponding
cross sections in the absence of an external field. Results obtained may be experimentally verified, for example,
by the scientific facilities at the SLAC National Accelerator Laboratory and FAIR (Facility for Antiproton and Ion
Research, Darmstadt, Germany).
PACS: 034.50.Rk, 12.20.-m
1. INTRODUCTION
Use of a powerful coherent light source in modern ap-
plied and fundamental research has stimulated study
of the external strong field influence on quantum elec-
trodynamic (QED) processes [1]. A characteristic
feature of electrodynamic processes of second order
in the fine-structure constant in a laser field is asso-
ciated with the fact that such processes may occur
under both nonresonant and resonant conditions [1]-
[5]. The resonant character relates to the fact that
lower-order processes, such as spontaneous emission
and one-photon creation and annihilation of electron-
positron pairs, may be allowed in the field of a light
wave. Therefore, within a certain range of energy
and momentum, a particle in an intermediate state
may fall within the mass shell. Then the considered
higher-order process is effectively reduced to two se-
quential lower-order processes [1]-[5]. The appear-
ance of resonances in a laser field is one of the funda-
mental problems of QED in strong fields.
As a result of laser technology development dif-
ferent types of coherent light sources have become
available, with intensities that have increased up to
1022W · cm−2 in recent years. The new experimental
conditions have required constant improvements in
calculations and model development. The amplitude
of the field intensity of powerful ultrashort pulsed
lasers changes greatly in space and time. In the de-
scription of QED processes in the presence of a pulsed
laser the external field is usually modeled as a plane
nonmonochromatic wave, when a characteristic pulse
width τ obeys the condition [2]-[5]
ωτ À 1. (1)
The four-potential of the pulsed plane wave propa-
gating along the z-axis has form [2]-[5]:
A (ϕ) = A0g
( ϕ
ωτ
)
(ex cos ϕ + δey sinϕ) , (2)
ϕ = (kx) = ω (t− z) ,
where A0 = F0/ω, k = (ω,k) is the wave vector,
F0, ω and δ are the strength, the frequency and
the ellipticity parameter of the wave, ex = (0, ex),
ey = (0, ey) are the four-vectors of wave polariza-
tion. The function in expression (2) g (ϕ/ωτ) is the
envelope function of the four-potential, which must
be equal the unit in center of a pulse, g (0) = 1, and
to decrease exponentially (g → 0) when ϕ À ωτ .
Following QED processes of the second order in
the fine structure constant in the pulsed laser field are
considered: resonant spontaneous bremsstrahlung by
an electron scattered by a nucleus [3], resonant pho-
tocreation of electron–positron pairs on a nucleus
[4], and resonant scattering of a lepton by a lepton
[5]. There are two characteristic parameters in these
processes of QED in the field of a pulsed electro-
magnetic wave. The first is the classical relativistic-
invariant parameter [1]-[5],
η0 =
eFoλ
mc2
, (3)
which in the pulse peak equals numerically the ratio
of work done by the field within the distance equal
to a wavelength to the electron rest energy (e and m
∗Corresponding author E-mail address: rsp@roshchupkin.sumy.ua
48 ISSN 1562-6016. PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2013, N3(85).
Series: Nuclear Physics Investigations (60), p.48-52.
are the charge and the mass of an electron, F0 and
λ = c/ω are the strength and the wave-length of an
electric field in the pulse peak). The Bunkin-Fedorov
quantum parameter is specified [1]-[5]:
γi =
mυic
~ω
. (4)
(υi is the electron speed). We treat these problems
of QED within the range of moderate-strong-field in-
tensities, when
η0 ¿ 1, γi & 1. (5)
Consequently, the quantum Bunkin-Fedorov parame-
ter is the main parameter which determines multi-
photon processes. Hereafter, we use the relativistic
system of units ~ = c = 1.
2. RESONANT BREMSSTRAHLUNG OF
AN ELECTRON SCATTERED BY AN ION
IN A PULSED LIGHT FIELD
Here we describe a theory of resonant spontaneous
bremsstrahlung (SB) produced by the scattering of
an electron by a Coulomb center in the presence
of pulsed external electromagnetic field (Fig. 1) [3].
The problem under consideration is of vast scien-
tific interest with respect to the concept substan-
tiation of electromagnetic interaction realization as
the virtual particle exchange. In the study of reso-
nant processes in the field of plane monochromatic
wave the resonance infinities were phenomenologi-
cally eliminated by Breit and Wigner procedure. The
main point of this procedure is that radiative correc-
tions in the Green function of an intermediate elec-
tron were included under consideration. It is impor-
tant to emphasize that the pulsed character of ex-
ternal field was taken into account in the study of
electron-nucleus SB. It enables to eliminate the reso-
nance infinity in the process amplitude by the sequen-
tial method in the frame of examined approaches [3].
Fig.1.Resonant SB related to the scattering of an
electron by a nucleus in the field of a pulsed light
wave. Here pi, pf are the four-momenta of initial
and final electrons; k′ is the four-momentum of
a spontaneous photon; qi is the four-momentum
of an intermediate electron; q is the transferred
momentum
The electron interaction with a nucleus is consid-
ered in the frame of the Born approximation, i.e. the
case of rather fast electrons is studied (υi À Z/137,
Z is the nucleus charge number). The process of
electron-nucleus SB in the presence of pulsed light
wave may occur under resonant conditions when the
four-momentum of an intermediate electron lies near
the mass surface
q2
i −m2 . (kqi)
ωτ
∼ m
τ
¿ ωm. (6)
Four characteristic domains of the resonant frequency
can be separated: in the nonrelativistic case, ωres ≈
ω; for an ultrarelativistic electron moving within a
narrow cone with the photon from the external field,
ωres ¿ ω; for an ultrarelativistic electron moving
within a narrow cone with the spontaneous photon,
ωres À ω; otherwise, ωres ∼ ω. The process of res-
onant electron–nucleus SB in the field of a pulsed
light wave can be effectively reduced to two sequential
processes of the first order in the fine-structure con-
stant: emission of a photon with a four-momentum
k′ by an electron pi in a pulsed light wave and scat-
tering of an electron qi by a nucleus in the field of
the pulsed wave (see Fig. 1). The resonant differen-
tial cross section of electron–nucleus SB in the field
of pulsed light wave for moderately strong intensities
when the electron is scattered by a large angle is:
dσres
dΩ′
=
1
π2
Eiω
′2|qi| (kpi)
(kk′)2 |pi|
PresdσsdW (1). (7)
Here dσs is the differential cross section of scattering
of an intermediate electron with a four-momentum qi
by a nucleus in the field of the wave, dW (1) is the
probability that an electron with a four-momentum
pi = (Ei, pi) absorbs one photon from the external
field and spontaneously emits a photon with a four-
momentum k′ = (ω′, k′),
Pres =π(ωτ)2
exp{−β2/2}
64(kqi)
1
2ρ
∫ ρ
−ρ
dφ|erf(φ+
iβ
2
)+1|2,
(8)
β =
q2
i −m2
4(kqi)
ωτ. (9)
The parameter β (9) specifies how close the four-
momentum of an intermediate electron coincides with
the value on the mass surface in the resonant condi-
tions. The dependence of the function Pres on the
parameter β defines a magnitude and a shape of the
resonant peak in the cross section of electron-nucleus
SB process in the pulsed light field. The parameter
ρ is the relation between observation time and pulse-
width. The function Pres can be easily written in the
form
Pres =
a1
(q2
i −m2)2 + (2mΓτ )2
, Γτ =
2√
a2
(kqi)
m(ωτ)
.
(10)
Here coefficients a1 and a2 weakly depend on the
parameter ρ. A transit resonant width Γτ arose
from the finite time of particle-field interaction.
49
Fig.2. The ratio Rres as a function of the electron
velocity for preset orientations of the electron
momentum in the initial and final states and fixed
orientation of the spontaneous photon (θ′ = 120o
and ϕ′ = 10o solid line; θ′ = 120o and ϕ′ = 60o
dashed line)
Let’s consider the relation between resonant dif-
ferential cross section of electron-nucleus SB and the
cross-section of electron-nucleus SB in an absence
of external field. The following parameters: the
laser wave frequency ω = 2.35 eV; the laser pulse-
width τ = 1.5 ps; the field strength in pulse peak
F0 = 6 · 109 V · cm−1 were chosen for the calculation.
Fig.2 displays ratio Rres as a function of the initial
velocity of the electron. As can be seen from Fig. 2,
within the range of relativistic electron energies, the
resonant differential cross section of electron–nucleus
SB may be five orders of magnitude higher than the
corresponding cross section in the absence of the ex-
ternal field. Within the range of ultrarelativistic elec-
tron energies, this ratio drastically decreases.
3. RESONANT PHOTOCREATION OF
ELECTRON–POSITRON PAIRS ON A
NUCLEUS IN A PULSED LIGHT FIELD
Here we describe a theory of resonant photocre-
ation of electron–positron pairs on a nucleus in a
pulsed light field (Fig. 3) [4]. The photocreation
process of electron–positron pairs on a nucleus in the
presence of pulsed light wave may occur under reso-
nant conditions when the four-momentum of an in-
termediate electron lies near the mass surface
q2
− −m2 . (kq−)
ωτ
¿ ωm. (11)
In this case resonances are possible only for an ul-
trarelativistic positron moving within a narrow cone
with the initial photon and the resonant frequency of
an initial photon is
ωres =
E+
1−Wth/E+
, Wth =
(1 + δ2
+)
4sin2(θi/2)
m2
ω
, (12)
δ+ = θ+(E+/m), θ+ = ∠(ki,p+) ¿ 1. (13)
Fig.3. Resonant photocreation of electron–positron
pairs on a nucleus in a pulsed light field. Here p−,
p+ are the four-momenta of electron and positron;ki
is the four-momentum of an initial photon; qi is the
four-momentum of an intermediate electron; q is
the transferred momentum
The resonant differential cross section of pho-
tocreation of electron–positron pairs on a nucleus in
the field of pulsed light wave for moderately strong
intensities when the electron is scattered by a large
angle is:
dσ(±)
res =
√
π
2
τ
8sin2(θi/2)
dσs(q−)dW
(1)
pair. (14)
Here dσs is the differential cross section of scat-
tering of an intermediate electron with a four-
momentum q− by a nucleus, dW
(1)
pair is the creation
probability of the electron-positron pair (q− and p+)
by initial photon ki as a result of absorption of one
photon from the laser field. Let’s consider the re-
lation between resonant differential cross section of
photocreation of electron–positron pairs on a nucleus
in the field of pulsed light wave and the corresponding
cross-section in an absence of laser field:
R(±)
res =
π
8
√
π
2
η2
0ωτ
[
ln
E+
m
]−1
. (15)
The following parameters: the laser wave frequency
ω = 1.17 eV; the laser pulse-width τ = 25 ps; para-
meter η0 ≈ 0.1; ωi = 5 ·105m = 255 GeV were chosen
for the calculation. We obtain from Eq. (15) the
relation R
(±)
res ≈ 40.
4. RESONANT SCATTERING OF A
LEPTON BY A LEPTON IN A PULSED
LIGHT FIELD
Here we describe a theory of resonant scattering
of a lepton by a lepton in a pulsed light field (Fig. 4)
[5].
The scattering of a lepton by a lepton in the pres-
ence of pulsed light wave may occur under resonant
conditions when the four-momentum of an interme-
diate photon lies near the mass surface
q′21 . (kq′1)
ωτ
∼ ω2
ωτ
¿ ω2. (16)
50
Fig.4. Resonant scattering of a lepton by a lepton
in a pulsed light field. Here p1, p2and p′1, p′2 are the
four-momenta of leptons for initial and final parti-
cles states, respectively; q′1 is the four-momentum of
an intermediate photon
The resonance appears if leptons scatter by each
other into the small angles in the frame of reference
related to the center of inertia
θres = 2
ω
|p| sinθi ¿ 1, (17)
where θi is the angle between directions of wave
propagation and initial relative momentum p.
Fig.5. The dependence of differential cross-section
of scattering of an electron by an electron (an
electron by a positron) in the pulsed light field (in
units of respective cross-sections in the external field
absence) on initial polar angle when azimuthal angle
is fixed
Let’s consider the ratio of derived resonant differ-
ential cross-section of scattering of leptons by each
other into elementary azimuthal angle to the differ-
ential cross section of scattering of respective lep-
tons in the external field absence for the most in-
teresting processes of scattering of a lepton by a
lepton: the scattering of an electron by an elec-
tron, the scattering of an electron by a positron, the
scattering of an electron by a muon. The experi-
mental investigation of processes of resonant scatter-
ing of a lepton by a lepton may be verified in the
fields created by picosecond pulsed lasers which gen-
erate radiation within the frequency optical range.
Fig.6. The dependence of differential cross-section
of scattering of an electron by muon in the pulsed
light field (in units of respective cross-sections in the
external field absence) on initial polar angle when
azimuthal angle is fixed
The Fig. 5-6 show the dependences of the consid-
ered ratio on initial polar angle θi. The external laser
wave frequency amounts to value ω = 2.35 eV, the
pulse-width is equal to τ = 1.5 ps, the field strength
in pulse peak is F0 = 6 · 109 V · cm−1. Hereby the
most exceeding appears for the particles small rel-
ative velocities case, at that the exceeding reaches
into five orders of magnitude in case of scattering of
an electron by an electron (positron), and two orders
in case of scattering of an electron by a muon.
5. CONCLUSIONS
• The QED processes of second order in the fine-
structure constant in the presence of a pulsed
light wave may occur under resonant conditions
when the four-momentum of an intermediate
particle lies near the mass surface.
• The resonant behavior of these processes is
specified by characteristics of the laser pulse.
The resonant singularity in the processes ampli-
tude is eliminated by accounting for the pulsed
character of the external field rather than by
the phenomenological Breit-Wigner procedure.
• The resonant differential cross sections of
the following processes proceeding in the
strong pulsed light fields: resonant sponta-
neous bremsstrahlung by an electron scattered
by a nucleus, resonant photocreation of elec-
tron–positron pairs on a nucleus, and resonant
scattering of a lepton by a lepton may be sev-
eral orders of magnitude higher than the cor-
responding cross sections in the absence of the
laser field.
• The obtained results may be experimentally
verified, for example, by the scientific facilities
at the SLAC National Accelerator Laboratory
and FAIR (Facility for Antiproton and Ion Re-
search, Darmstadt, Germany).
51
References
1. S.P. Roshchupkin and A.I. Voroshilo. Resonant
and Coherent Effects of Quantum Electrodynam-
ics in the Light Field. Kiev: “Naukova Dumka”,
2008, 399 p. (in Russian).
2. S.P. Roshchupkin, A.A. Lebed’, E.A. Padusenko,
and A.I. Voroshilo. Quantum Electrodynamics
Resonances in a Pulsed Laser Field // Laser
Physics. 2012, v. 22, p. 1113-1144.
3. A.A. Lebed’ and S.P. Roshchupkin. Resonant
spontaneous bremsstrahlung by an electron scat-
tered by a nucleus in the field of a pulsed light
wave // Phys. Rev. A 2010, v. 81, p.033413.
4. A.A. Lebed’ and S.P. Roshchupkin. Resonant
electron–positron pair photoproduction on a nu-
cleus in a pulsed light field // JETP. 2011, v. 113,
p. 46-54.
5. E.A. Padusenko, S.P. Roshchupkin. Resonant
scattering of a lepton by a lepton in the pulsed
light field // Laser Phys. 2010, v. 20, p. 2080-2091.
КВАНТОВАЯ ЭЛЕКТРОДИНАМИКА В СИЛЬНЫХ ИМПУЛЬСНЫХ ЛАЗЕРНЫХ
ПОЛЯХ
С.П.Рощупкин
Рассматриваются некоторые резонансные процессы квантовой электродинамики (КЭД), протекающие
в сильных импульсных световых полях, реализуемых в современных мощных импульсных лазерах.
Появление резонансов в лазерном поле является одной из фундаментальных проблем КЭД в электро-
магнитных полях. Рассматриваются следующие процессы КЭД второго порядка по постоянной тонкой
структуры в импульсном лазерном поле: резонансное спонтанное тормозное излучение электрона, рас-
сеянного на ядре; резонансное фоторождение электрон-позитронных пар на ядре и резонансное рассея-
ние лептона на лептоне. Амплитуда и ширина резонансных пиков определяются параметрами внешней
импульсной волны. Показано, что резонансные поперечные сечения могут быть на несколько порядков
величины больше, чем соответствующие поперечные сечения в отсутствие внешнего поля. Получен-
ные результаты могут быть экспериментально проверены в научных коллоборациях, таких как SLAC
(National Accelerator Laboratory) и FAIR (Facility for Antiproton and Ion Research, Darmstadt, Germany).
КВАНТОВА ЕЛЕКТРОДИНАМIКА В СИЛЬНИХ IМПУЛЬСНИХ ЛАЗЕРНИХ
ПОЛЯХ
С.П.Рощупкiн
Розглядаються деякi резонанснi процеси квантової електродинамiки (КЕД), що протiкають у сильних
iмпульсних свiтлових полях, реалiзованих у сучасних потужних iмпульсних лазерах. Поява резонансiв
у лазерному полi є однiєю з фундаментальних проблем КЕД в електромагнiтних полях. Розглядають-
ся наступнi процеси КЕД другого порядку зi сталої тонкої структури в iмпульсному лазерному полi:
резонансне спонтанне гальмове випромiнювання електрона, розсiянного на ядрi; резонансне фотона-
родження електрон-позитронних пар на ядрi й резонансне розсiювання лептона на лептонi. Амплiтуда
й ширина резонансних пiкiв визначаються параметрами зовнiшньої iмпульсної хвилi. Показано, що
резонанснi поперечнi перерiзи можуть на декiлька порядкiв величини бути бiльше, нiж вiдповiднi по-
перечнi перерiзи у вiдсутностi зовнiшнього поля. Отриманi результати можуть бути експериментально
перевiренi в наукових об’єднаннях, таких як SLAC (National Accelerator Laboratory) i FAIR (Facility for
Antiproton and Ion Research, Darmstadt, Germany).
52
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