Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator
The results of numerical PIC-simulation of the dynamics of accelerated positron and drive electron bunches under wake acceleration in a dielectric waveguide filled with plasma with a vacuum channel are presented. The wake field was excited by an electron bunch in a quartz dielectric tube inserted in...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2023
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| Цитувати: | Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator / P.I. Markov, R.R. Kniaziev, G.V. Sotnikov // Problems of Atomic Science and Technology. — 2023. — № 4. — С. 61-66. — Бібліогр.: 18 назв. — англ. |
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Markov, P.I. Kniaziev, R.R. Sotnikov, G.V. 2023-12-11T11:51:43Z 2023-12-11T11:51:43Z 2023 Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator / P.I. Markov, R.R. Kniaziev, G.V. Sotnikov // Problems of Atomic Science and Technology. — 2023. — № 4. — С. 61-66. — Бібліогр.: 18 назв. — англ. 1562-6016 PACS: 41.75.Ht, 41.75.Lx, 41.75.Jv, 96.50.Pw DOI: https://doi.org/10.46813/2023-146-061 https://nasplib.isofts.kiev.ua/handle/123456789/196175 The results of numerical PIC-simulation of the dynamics of accelerated positron and drive electron bunches under wake acceleration in a dielectric waveguide filled with plasma with a vacuum channel are presented. The wake field was excited by an electron bunch in a quartz dielectric tube inserted into a cylindrical metal waveguide. The inner region of the dielectric tube was filled with plasma with a vacuum channel along the waveguide axis. The difference in the energy and spatial characteristics, acceleration efficiency, emittance, and energy spread for positron and electron bunches is studied for different radii of the vacuum channel and two models of the plasma density dependence on the radius: a homogeneous and an inhomogeneous dependence characteristic of a capillary discharge. Наведено результати чисельного PIC-моделювання динаміки прискореного позитронного та драйверного електронного згустків при кільватерному прискоренні в діелектричному хвилеводі, заповненому плазмою з вакуумним каналом. Кільватерне поле збуджувалося електронним згустком у кварцовій діелектричній трубці, вставленій у циліндричний металевий хвилевід. Внутрішня область діелектричної трубки була заповнена плазмою з вакуумним каналом вздовж осі хвилеводу. Досліджено відмінність в енергетичних та просторових характеристиках, ефективності прискорення, емітансі та енергетичному розкиді для позитронного та електронного згустків при різних радіусах вакуумного каналу та двох моделях залежності щільності плазми від радіусa: однорідної та неоднорідної залежності характерної для капілярного розряду. The study is supported by the National Research Foundation of Ukraine under the program “Leading and Young Scientists Research Support” (project # 2020.02/0299). en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Problems of Atomic Science and Technology New methods of charged particles acceleration Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator Дослідження параметрів електронних і позитронних згустків у плазмово-діелектричному кільватерному прискорювачі Article published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| spellingShingle |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator Markov, P.I. Kniaziev, R.R. Sotnikov, G.V. New methods of charged particles acceleration |
| title_short |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| title_full |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| title_fullStr |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| title_full_unstemmed |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| title_sort |
investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator |
| author |
Markov, P.I. Kniaziev, R.R. Sotnikov, G.V. |
| author_facet |
Markov, P.I. Kniaziev, R.R. Sotnikov, G.V. |
| topic |
New methods of charged particles acceleration |
| topic_facet |
New methods of charged particles acceleration |
| publishDate |
2023 |
| language |
English |
| container_title |
Problems of Atomic Science and Technology |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Дослідження параметрів електронних і позитронних згустків у плазмово-діелектричному кільватерному прискорювачі |
| description |
The results of numerical PIC-simulation of the dynamics of accelerated positron and drive electron bunches under wake acceleration in a dielectric waveguide filled with plasma with a vacuum channel are presented. The wake field was excited by an electron bunch in a quartz dielectric tube inserted into a cylindrical metal waveguide. The inner region of the dielectric tube was filled with plasma with a vacuum channel along the waveguide axis. The difference in the energy and spatial characteristics, acceleration efficiency, emittance, and energy spread for positron and electron bunches is studied for different radii of the vacuum channel and two models of the plasma density dependence on the radius: a homogeneous and an inhomogeneous dependence characteristic of a capillary discharge.
Наведено результати чисельного PIC-моделювання динаміки прискореного позитронного та драйверного електронного згустків при кільватерному прискоренні в діелектричному хвилеводі, заповненому плазмою з вакуумним каналом. Кільватерне поле збуджувалося електронним згустком у кварцовій діелектричній трубці, вставленій у циліндричний металевий хвилевід. Внутрішня область діелектричної трубки була заповнена плазмою з вакуумним каналом вздовж осі хвилеводу. Досліджено відмінність в енергетичних та просторових характеристиках, ефективності прискорення, емітансі та енергетичному розкиді для позитронного та електронного згустків при різних радіусах вакуумного каналу та двох моделях залежності щільності плазми від радіусa: однорідної та неоднорідної залежності характерної для капілярного розряду.
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/196175 |
| citation_txt |
Investigation of parameters of electron and positron bunches in a plasma-dielectric wakefield accelerator / P.I. Markov, R.R. Kniaziev, G.V. Sotnikov // Problems of Atomic Science and Technology. — 2023. — № 4. — С. 61-66. — Бібліогр.: 18 назв. — англ. |
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2025-11-26T03:58:06Z |
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2025-11-26T03:58:06Z |
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| fulltext |
ISSN 1562-6016. Problems of Atomic Science and Technology. 2023. № 4(146) 61
https://doi.org/10.46813/2023-146-061
INVESTIGATION OF PARAMETERS OF ELECTRON AND POSITRON
BUNCHES IN A PLASMA-DIELECTRIC WAKEFIELD ACCELERATOR
P.I. Markov, R.R. Kniaziev, G.V. Sotnikov
National Science Center “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine
E-mail: pmarkov@kipt.kharkov.ua
The results of numerical PIC-simulation of the dynamics of accelerated positron and drive electron bunches un-
der wake acceleration in a dielectric waveguide filled with plasma with a vacuum channel are presented. The wake
field was excited by an electron bunch in a quartz dielectric tube inserted into a cylindrical metal waveguide. The
inner region of the dielectric tube was filled with plasma with a vacuum channel along the waveguide axis. The dif-
ference in the energy and spatial characteristics, acceleration efficiency, emittance, and energy spread for positron
and electron bunches is studied for different radii of the vacuum channel and two models of the plasma density de-
pendence on the radius: a homogeneous and an inhomogeneous dependence characteristic of a capillary discharge.
PACS: 41.75.Ht, 41.75.Lx, 41.75.Jv, 96.50.Pw
INTRODUCTION
Recently, to improve the bunch transport in dielec-
tric wakefield accelerators (DWA) it was proposed to
use the filling of the vacuum channel with plasma [1].
Subsequent more detailed studies (theoretical and
experimental) showed that plasma-filled dielectric
wakefield accelerators (PDWAs) make it possible to
reduce the transverse size of the accelerated bunches
[2 - 5] and suppress beam breakup instability [6].
Compact PDWAs with a higher acceleration gradi-
ent than conventional RF accelerators can find applica-
tion in different areas of industry, technology, medicine,
etc. However, if we consider the PDWA in relation to
high energy physics as a possible candidate for future
electron-positron colliders, it is necessary that the quali-
ty of accelerated bunches meet the collider requirements
[7 - 12]. The quality of accelerated bunches is character-
ized by the following characteristics: emittance and en-
ergy spread. We have already begun to study these
characteristics for positron bunches in the PDWA with
an axial vacuum channel inside the plasma column. We
started with the study of the transport of positron
bunches [13], because this is a more challengeable task
than the transport of electron bunches. This problem is
similar to that of the PWFA method and a vacuum
channel is used to mitigate it [14].
In present paper we continue our research of accel-
eration of positron bunch in PDWA [13]. We have in-
creased the acceleration length and in more detail inves-
tigated dynamic characteristics of accelerated positron
and drive electron bunches (emittance, energy spread,
efficiency of energy transfer from the drive electron
bunch to the witness positron bunch) to see if these stats
could saturate with acceleration time. In addition, we
investigate the dependences from the size of the vacuum
channel.
The article is organized as follows. Section 1 pre-
sents the statement of the problem. The results of the
2.5-dimensional PIC-simulation of positron acceleration
in PDWA are presented in Section 2. In Section 3 char-
acteristics of the accelerated positron bunch (emittance,
energy spread and efficiency) are given. In Conclusions
are summarized main results.
1. THE PROBLEM DEFINITION
The statement of the problem is the next. A dielec-
tric tube with inner radius a and outer b , inserted into
cylindrical metal waveguide; the internal area of dielec-
tric tube is filled with annular plasma with inner radius
1pr and outer radius a . Thus, the paraxial region
1pr r is a vacuum channel. The cylindrically shaped
drive electron bunch of radius
1br pass through the
slowing-down structure along its axis and excite a
wakefield. After the delay time
delt following the drive
bunch, positron bunch with an absolute value of charge
much smaller than that of the drive bunch, is injected in
the system along its axis. The radius of positron bunch
is
2br . The plasma-filled structure with the drive elec-
tron bunch and the witness positron bunch is the plasma
dielectric wakefield accelerator of positrons (PDWAP).
For numerical simulation of drive electron and test
positron bunch dynamics we used own 2.5D particle-in-
cell (PIC) code [1]. The parameters of the structure and
bunches, used in the simulations are specified in Table.
The parameters of the waveguide, drive and witness
(test) bunches, employed in PDWAP calculations
Inner radius of dielectric tube, a 0.5 mm
Outer radius of dielectric tube, b 0.6 mm
Inner plasma cylinder radius, rp1 0…0.5 mm
Waveguide length, L 80 mm
Dielectric permittivity, ε 3.75
Bunch energy, E0 5 GeV
Drive electron bunch charge –3 nC
Witness (test) positron bunch charge 0.05 nC
Longitudinal rms deviation of drive bunch
charge, 2σ1 (Gauss charge distribution)
0.1 mm
Longitudinal rms deviation of positron bunch
charge, 2σ2 (Gauss charge distribution)
0.05 mm
Total drive bunch length in PIC simulation 0.2 mm
Total positron bunch length in PIC simulation 0.1 mm
Drive bunch diameter, 2rb1 0.9 mm
Positron bunch diameter, 2rb2 0.7 mm
Paraxial plasma density (np0) when rp1 = 0 2∙10
14
cm
-3
62 ISSN 1562-6016. Problems of Atomic Science and Technology. 2023. № 4(146)
Fig. 1. Models of plasma density-radius relationship
pn r for two cases: the plasma fills completely the
interior of the dielectric tube (dash lines) and the plas-
ma cylinder of internal radius
p1r = 0.2 mm (solid lines).
Red line (2) corresponds to the inhomogeneous
distribution of plasma density [15], cyan line (1)
is for the homogeneous one
When simulating plasma two different models of the
plasma density-radius relationship pn r are studied:
1) the homogeneous model and 2) the inhomogeneous
dependence, characteristic to the capillary discharge
[15]. In the general case, there is a vacuum channel in-
side the plasma. At the vacuum-plasma boundary at
1pr r the stepwise behavior of pn r as a functions of
radius r is assumed. Examples of these dependencies
for the case
1 0.2pr mm and
1 0pr (no vacuum
channel) are shown in Fig. 1. A homogeneous profile of
a hollow core plasma channel can easily be obtained by
the high order Bessel beams [14, 16]. As for a hollow
core plasma from the capillary discharge, a coaxial ge-
ometry of the DWA structure with two dielectric tubes,
can be suitable. The wall thickness of the inner coaxial
has to be significantly smaller than the wall thickness of
the outer capillary, so that it does not change the fre-
quency of the main accelerating mode.
2. RESULTS OF 2.5-DIMENSIONAL
PIC-SIMULATION
Dependence of test bunch radius on the inner plasma
tube radius from 0 to 0.5 mm at time 266.9 pst is
shown in Fig. 2 (top panel).
As appears from the curves shown in Fig. 2 for the
homogeneous plasma distribution as
1pr increases from
0 to 0.25 mm, the gradual increase in the test positron
bunch focusing is observed. With a further
1pr increase
to 0.35 mm (a positron bunch radius), the focusing
slightly reduces. Further increase of
1pr leads to a dras-
tic degradation in the test bunch focusing. If
1 0.4pr mm the test bunch focusing is practically ab-
sent. In case of inhomogeneous transverse profile of
plasma density, a gradual increase in the test positron
bunch focusing is observed with an 1pr increase from
0 to 0.37 mm (see Fig. 2). It should be noted that the
behavior of bunch radius dependencies differ a slightly
from presented in paper [13], especially for the case of
homogeneous plasma density distribution in drift chan-
nel.
Fig. 2. Behavior of radiuses
maxR of bunches (above)
and energy change of the accelerated test positron
bunch and the slowed-down drive electron bunch
at change of smaller plasma tube radius
p1r for time
t 266.9 ps for different plasma density dependences
on radius
Lower panel of Fig. 2 show the energy gain E of
the test bunch (blue curve) and the slowed-down drive
bunch (red curve) as function of the inner plasma-tube
radius
1pr . With
1pr increase from 0 to 0.25 mm, a
small energy gain E reduction of the test bunch is
observed. The further
1pr increase from 0.25 to 0.5 mm
leads to E increase of the test bunch. The dependence
of drive bunch energy loss is given for homogeneous
plasma density case, for the inhomogeneous plasma
density case in drift channel, an obtained dependence is
practically coincides with the depicted one.
3. CHARACTERISTICS OF ACCELERATED
POSITRON AND DRIVE ELECTRON
BUNCHES
Here we study the characteristics of the accelerated
positron and drive electron bunches. Figs. 3-5 show the
efficiency of energy transfer to the positron bunch from
the drive electron bunch, the trace-space emittance of
the positron and electron bunches, and their energy
spread. For the calculation of the efficiency of energy
transfer of drive bunch to the witness bunch, we used
the following equation:
0
1
0
1
100%
ac
dr
N
ac ac ac
i i i
i
tr N
dr dr dr
i i i
i
m
m
,
where ac
im and dr
im are the masses of macroparticles of
the witness bunch and the drive bunch; ac
i and dr
i are
the relativistic factors of the macroparticles of the wit-
ness bunch and the drive bunch; 0
ac
i and 0
dr
i their ini-
tial values;
acN and
drN are the number of macroparti-
cles in the witness bunch and the drive bunch.
The maximum efficiency was about 3.21% and
achieved when the drift channel was completely free
from plasma. The minimum of efficiency was achieved
when 1pr provide the best positron bunch focusing what
ISSN 1562-6016. Problems of Atomic Science and Technology. 2023. № 4(146) 63
can be seen in Fig. 3, c, d: in the inhomogeneous case it
is ≈ 1.92%; in the homogeneous case it is ≈ 1.90%. In
the presence of a vacuum channel, the efficiency is
smaller, that is associated with a smaller value of the
accelerating field.
Fig. 4 shows the change in the trace-space emittance
[17] of positron and electron bunches as positron bunch
accelerates in the PDWA. For a cylindrically symmetric
on-axis beam, it is calculated by the formulas [18]:
2 221
4
tr r r r r ,
where
2 2
1 1
2 2 2
1 1
1 1
, ,
1 1
,
N N
ri
i i i i
zii i
N N
i i i ri zi
i i
v
r q r r r q r
Q Q v
r q r q v v
Q Q
, , ,i i ri ziq r v v are charge, radius, radial and longitudinal
macroparticle velocity, Q is total bunch charge, N is
number of macroparticles in the bunch.
Fig. 3. Transfer energy efficiency tr from the drive electron bunch to the witness positron bunch versus time:
a, c correspond the inhomogeneous plasma density; b, d the homogeneous plasma density in the drift channel;
a, b are the 2D charts; c, d 3D charts with p1r as the depth axis. Time t = 0 corresponds to the beginning
of the injection of the drive electron bunch
As follows from Fig. 4 trace-space emittance of the
positron beam increases during acceleration in the
PDWA, but after travelling ≈ 70 mm it is increased to
acceptable values. The smallest value of the emittance
57.9 10 mmmrad is realized for the case when the
drift channel is completely free from plasma. The larg-
est value of the emittance is obtained in the case of best
positron bunch focusing what can be seen in Fig. 4, d, e:
in the inhomogeneous plasma density in the drift chan-
nel case it is
24.51 10 mmmrad, in the homogeneous
case it is
24.65 10 mmmrad. It can be seen that even
for this non-optimal case, there is already a tendency to
reach saturation. Extrapolating the above curves with
the parabolic quadratic dependencies, we obtain that in
the case of homogeneous plasma the emittance at the
maximum is 34.67 10 mmmrad and is achieved at
an acceleration length of ≈ 94 mm, and in the case of
inhomogeneous plasma, the emittance at the maximum
is 24.6 10 mmmrad and is achieved at the accelera-
tion length of ≈ 150 mm. In the case of incomplete fill-
ing the trace-space emittances turn out to be higher,
both in the homogeneous and the inhomogeneous cases
of plasma, and their value are approximately the same.
a b
c
d
64 ISSN 1562-6016. Problems of Atomic Science and Technology. 2023. № 4(146)
Fig. 4. Trace-space emittance of the witness positron bunch (a, b, d, e) and drive electron bunch (c, f) versus time:
a, d correspond the inhomogeneous plasma density; b, e the homogeneous plasma density
in the drift channel; a, b, c are the 2D charts; d, e, f 3D charts with p1r as the depth axis
Trace-space emittance of electron driver is signifi-
cantly smaller than emittance of positron witness and
reach 36.42 10 mmmrad value at 1 0pr . In our case
the saturation of drive electron bunch emittance occurs
when plasma leaves a bunch boundary. However, the
deterioration of the emittance of the drive bunch is not
yet critical for continuing the process of positron bunch
acceleration.
In Fig. 4, d, e, f one can see that when plasma leaves
a bunch boundary the trace-space emittances sharply
decreases to values 57.87 10 mmmrad for positron
witness (see Fig. 4, a, b, d, e) and 43.36 10 mmmrad
for electron driver (see Fig. 4, c, f).
In Fig. 5 is shown the change of the energy spread of
the positron and electron bunches when positron bunch
accelerates along the PDWA.
Fig. 5. Energy spread of the witness positron bunch (a, b, d, f) and driver electron bunch (c, f) versus time:
a, d correspond the inhomogeneous plasma density; b, e the homogeneous plasma density in the drift channel;
a, b, c are the 2D charts; d, e, f 3D charts with p1r as the depth axis
Energy spread in our simulations for unequally
weighted macroparticles is computed using the next
equation:
(% ) 100RMSRMS E E ,
d e f
c b a
a b c
d e f
ISSN 1562-6016. Problems of Atomic Science and Technology. 2023. № 4(146) 65
where
22 2 2
1
1
1
, ,
1
, 1,
N
RMS i i
i
N
i i i i
i
E E E E q E
Q
E q E E
Q
i is the relativistic factor of the macroparticle.
Changes in the energy spread of the positron bunch
during its acceleration are shown in the Fig. 5, a, d and
Fig. 5, b, e. The smallest energy spread is realized in the
case of complete filling of the drift channel of the die-
lectric structure with plasma and is equal to 0.01% for
the case of the capillary discharge and 0.012% for the
homogenous plasma case. These values are significantly
lower than the requirements for collider applications [7,
18]. The spread has not yet reached saturation, but there
is already a tendency for it to saturate. At the maximum
using the parabolic extrapolation we obtain the energy
spread of ∼ 0.015% for the case of the capillary dis-
charge.
The largest energy spread is realized in the case when
1 0.375pr mm, i.e. when radius of vacuum tube is
greater then positron bunch radius and is equal to 0.024%
for the case of the capillary discharge and 0.022% for the
homogenous plasma case. At further increase in 1pr the
energy spread sharply falls down to the minimum value.
Changes in the energy spread of the electron bunch
at its motion in the drift chamber is shown in the
Fig. 5, c, d. Practically, ( )t represents linear relation
from time t . Dependence of 1( )pr on the vacuum
cylinder radius 1pr is weak. The largest driver energy
spread is realized in the case of complete filling of the
drift channel of the dielectric structure with plasma and
is equal to 0.13%. The smallest driver energy spread is
realized in the case when the drift channel was com-
pletely free from plasma and is equal to 0.11%.
CONCLUSIONS
In this article, the main attention is paid to the study
of the characteristics of accelerated positron and driver
electron bunches by the numerical PIC simulation of
wake excitation and self-consistent dynamics of charged
particles in a plasma-dielectric slow-wave structure of
the THz-band with both a homogeneous model plasma
and an inhomogeneous plasma generated by a capillary
discharge in waveguide.
We also showed that the presence of plasma in the
system leads to focusing of an accelerated positron
bunch, and the presence of a paraxial vacuum channel
increases focusing by 9.25% in the case of a homogene-
ous plasma model and by 17.12% in the case of inho-
mogeneous plasma. In the absence of plasma, there is
no focusing of the positron bunch, and the increase in
positron energy gain is 36.8 and 34.6% higher than in
the presence of homogeneous and inhomogeneous
plasma, respectively, and the highest focusing of the
bunch.
A study of the energy transfer efficiency from an
electron beam to a positron one showed that the maxi-
mum efficiency of 3.21% is achieved in the plasma ab-
sence and the minimum is 1.90 and 1.92% in the homo-
geneous and inhomogeneous plasma presence, respec-
tively, and the highest focusing of the bunch.
An analysis of the emittance showed that the pres-
ence of plasma in the system significantly increases the
emittance of the beams, and the presence of a vacuum
channel increases the emittance of the positron bunch
even more. Thus, for a vacuum channel corresponding
to maximum focusing, the positron beam emittance
reaches values 24.65 10 mmmrad and
24.51 10 mmmrad in the presence of homogeneous
and inhomogeneous plasma, respectively, while in the
absence of a vacuum channel, the emittance decreases
to 33.85 10 mmmrad and 21.29 10 mmmrad for the
studied plasma models, respectively. In the absence of
plasma, the value of the maximum emittance of the pos-
itron beam is 57.87 10 mmmrad.
At the same time, the presence of a vacuum channel
in the plasma leads to a decrease in the emittance of the
drive electron bunch. When the drift channel is complete-
ly filled with plasma, the emittance of the electron bunch
is 36.42 10 mmmrad, and in the plasma absence case,
the emittance drops to 43.36 10 mmmrad. The great-
est change in the emittance is observed when the vacu-
um channel radius is close to the radius of the charged
particles bunch.
The presence of a vacuum channel also leads to an
increase in the energy spread of the positron bunch par-
ticles. Thus, when the drift channel is completely filled
with plasma, the scatter is 0.01%, while for a vacuum
channel corresponding to maximum focusing, the ener-
gy spread increases to 0.022 and 0.024% in the cases of
homogeneous and inhomogeneous plasma, respectively.
The filling of the drift channel with plasma and the
presence of a vacuum channel in the plasma have a
much smaller effect on the energy spread of the driver
electron bunch particles than on the positron bunch
spread. If, when the drift channel is completely filled
with plasma, the energy spread of electrons is 0.13%,
then in the plasma absence case, the spread decreases to
0.11%.
ACKNOWLEDGEMENTS
The study is supported by the National Research
Foundation of Ukraine under the program “Leading and
Young Scientists Research Support” (project #
2020.02/0299).
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Article received 23.06.2023
ДОСЛІДЖЕННЯ ПАРАМЕТРІВ ЕЛЕКТРОННИХ І ПОЗИТРОННИХ ЗГУСТКІВ
У ПЛАЗМОВО-ДІЕЛЕКТРИЧНОМУ КІЛЬВАТЕРНОМУ ПРИСКОРЮВАЧІ
П.І. Марков, Р.Р. Князєв, Г.В. Сотніков
Наведено результати чисельного PIC-моделювання динаміки прискореного позитронного та драйверного
електронного згустків при кільватерному прискоренні в діелектричному хвилеводі, заповненому плазмою з
вакуумним каналом. Кільватерне поле збуджувалося електронним згустком у кварцовій діелектричній труб-
ці, вставленій у циліндричний металевий хвилевід. Внутрішня область діелектричної трубки була заповнена
плазмою з вакуумним каналом вздовж осі хвилеводу. Досліджено відмінність в енергетичних та просторо-
вих характеристиках, ефективності прискорення, емітансі та енергетичному розкиді для позитронного та
електронного згустків при різних радіусах вакуумного каналу та двох моделях залежності щільності плазми
від радіусa: однорідної та неоднорідної залежності характерної для капілярного розряду.
https://doi.org/10.1051/epjconf/%20201714902011
https://doi.org/10.1088/1748-0221/15/09/C09001
https://doi.org/10.1016/j.nima.2018.01.028
https://vant.kipt.kharkov.ua/ARTICLE/%20VANT_2016_6/article_2016_6_133.pdf
https://vant.kipt.kharkov.ua/ARTICLE/%20VANT_2016_6/article_2016_6_133.pdf
http://doi.org/10.1088/1748-0221/17/11/P11013
http://doi.org/10.1088/1748-0221/17/11/P11013
https://doi.org/10.1038/ncomms11785
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