Performance analysis of 30 MeV electron linac with a new injector system
The present paper deals with the problems of 30 MeV electron linear accelerator (LINAC-30) upgrading to attain optimum beam spectral characteristics. As one of the LINAC-30 upgrading variants, consideration has been given to a possible use of the injection system for LINAC-30, which is in general...
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| Zitieren: | Performance analysis of 30 MeV electron linac with a new injector system / S.P Gokov, L.A. Makhnenko, I.V. Khodak, O.A. Shopen // Вопросы атомной науки и техники. — 2009. — № 5. — С. 141-146. — Бібліогр.: 2 назв. — англ. |
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irk-123456789-966762016-03-19T03:02:47Z Performance analysis of 30 MeV electron linac with a new injector system Gokov, S.P. Makhnenko, L.A. Khodak, I.V. Shopen, O.A. Теория и техника ускорения частиц The present paper deals with the problems of 30 MeV electron linear accelerator (LINAC-30) upgrading to attain optimum beam spectral characteristics. As one of the LINAC-30 upgrading variants, consideration has been given to a possible use of the injection system for LINAC-30, which is in general similar to the 60 MeV electron linear accelerator (LINAC-60) injector and which includes a low-voltage 25keV electron source and a five-cavity standingwave buncher. Two possible configurations of the upgraded accelerator have been considered. Schematically, they can be represented as follows: 1) a new injector and a long section (4.41 m) of the basic accelerating channel; 2) a new injector, a short (0.83 m) section (section N 1) currently operating at a retarded phase velocity of the wave, and a long section (section N 2). Numerical modelling of particle dynamics in the accelerating channel has been performed for the two cases. Based on the results obtained, assumptions are made as to the most optimum configuration of the upgraded accelerator. Дана робота присвячена питанням модернiзацiї лiнiйного прискорювача електронiв (ЛПЕ-30) з метою отримання оптимальних спектральних характеристик пучка. Як один з варiантiв реконструкцiї прискорювача ЛПЕ-30 розглянута можливiсть використання в якостi iнжекторної системи для нього пристрiй, в цiлому подiбний iнжектору ЛПЕ-60, який включає в себе низьковольтне джерело электронiв 25 кеВ i 5-резонаторний групирувальник на стоячiй хвилi. Розглянутi двi можливi конфiгурацiї модернiзованого прискорювача, схеми яких можна представити як: новий iнжектор та довга секцiя (4.41 м)основного прискорюючого тракту; новий iнжектор, коротка (0.83 м) секцiя (секцiя N1), яка працює в даний час з пониженою фазовою швидкiстюю хвилi, та довга секцiя (секцiя N2). Для обох випадкiв проведено чисельне моделювання динамiки часток в прискорюючому трактi. На основi отриманих результатiв висловлюються припущення про найбiльш оптимальну конфигурацiю модернiзованого прискорювача Данная работа посвящена вопросам модернизации линейного ускорителя электронов (ЛУЭ-30) с целью получения оптимальных спектральных характеристик пучка. Как один из вариантов реконструкции ускорителя ЛУЭ-30 рассмотрена возможность использования в качестве инжекторной системы для него устройство, в целом подобное инжектору ЛУЭ-60, включающее низковольтный источник электронов 25 кэВ и 5-резонаторный группирователь на стоячей волне. Рассмотрены две возможные конфигурации модернизированного ускорителя, схемы которых можно представить как: новый инжектор и длинная секция (4.41 м) основного ускоряющего тракта; новый инжектор, короткая (0.83 м) секция (секция N1), работающая в настоящее время с пониженной фазовой скоростью волны, и длинная секция (секция N2). Для обоих случаев проведено численное моделирование динамики частиц в ускоряющем тракте. На основе полученных результатов высказываются предположения о наиболее оптимальной конфигурации модернизированного ускорителя. 2009 Article Performance analysis of 30 MeV electron linac with a new injector system / S.P Gokov, L.A. Makhnenko, I.V. Khodak, O.A. Shopen // Вопросы атомной науки и техники. — 2009. — № 5. — С. 141-146. — Бібліогр.: 2 назв. — англ. 1562-6016 PACS: 29.20Ej http://dspace.nbuv.gov.ua/handle/123456789/96676 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 |
Теория и техника ускорения частиц Теория и техника ускорения частиц |
| spellingShingle |
Теория и техника ускорения частиц Теория и техника ускорения частиц Gokov, S.P. Makhnenko, L.A. Khodak, I.V. Shopen, O.A. Performance analysis of 30 MeV electron linac with a new injector system Вопросы атомной науки и техники |
| description |
The present paper deals with the problems of 30 MeV electron linear accelerator (LINAC-30) upgrading to attain
optimum beam spectral characteristics. As one of the LINAC-30 upgrading variants, consideration has been given
to a possible use of the injection system for LINAC-30, which is in general similar to the 60 MeV electron linear
accelerator (LINAC-60) injector and which includes a low-voltage 25keV electron source and a five-cavity standingwave
buncher. Two possible configurations of the upgraded accelerator have been considered. Schematically, they
can be represented as follows: 1) a new injector and a long section (4.41 m) of the basic accelerating channel; 2) a new
injector, a short (0.83 m) section (section N 1) currently operating at a retarded phase velocity of the wave, and a
long section (section N 2). Numerical modelling of particle dynamics in the accelerating channel has been performed
for the two cases. Based on the results obtained, assumptions are made as to the most optimum configuration of the
upgraded accelerator. |
| format |
Article |
| author |
Gokov, S.P. Makhnenko, L.A. Khodak, I.V. Shopen, O.A. |
| author_facet |
Gokov, S.P. Makhnenko, L.A. Khodak, I.V. Shopen, O.A. |
| author_sort |
Gokov, S.P. |
| title |
Performance analysis of 30 MeV electron linac with a new injector system |
| title_short |
Performance analysis of 30 MeV electron linac with a new injector system |
| title_full |
Performance analysis of 30 MeV electron linac with a new injector system |
| title_fullStr |
Performance analysis of 30 MeV electron linac with a new injector system |
| title_full_unstemmed |
Performance analysis of 30 MeV electron linac with a new injector system |
| title_sort |
performance analysis of 30 mev electron linac with a new injector system |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2009 |
| topic_facet |
Теория и техника ускорения частиц |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/96676 |
| citation_txt |
Performance analysis of 30 MeV electron linac with a new injector system / S.P Gokov, L.A. Makhnenko, I.V. Khodak, O.A. Shopen // Вопросы атомной науки и техники. — 2009. — № 5. — С. 141-146. — Бібліогр.: 2 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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AT gokovsp performanceanalysisof30mevelectronlinacwithanewinjectorsystem AT makhnenkola performanceanalysisof30mevelectronlinacwithanewinjectorsystem AT khodakiv performanceanalysisof30mevelectronlinacwithanewinjectorsystem AT shopenoa performanceanalysisof30mevelectronlinacwithanewinjectorsystem |
| first_indexed |
2025-07-07T03:55:32Z |
| last_indexed |
2025-07-07T03:55:32Z |
| _version_ |
1836958909965795328 |
| fulltext |
PERFORMANCE ANALYSIS OF 30 MeV ELECTRON LINAC
WITH A NEW INJECTOR SYSTEM
S.P Gokov, L.A. Makhnenko, I.V. Khodak, O.A. Shopen
National Science Center ”Kharkov Institute of Physics and Technology”, 61108, Kharkov, Ukraine
(Received July, 2009)
The present paper deals with the problems of 30 MeV electron linear accelerator (LINAC-30) upgrading to attain
optimum beam spectral characteristics. As one of the LINAC-30 upgrading variants, consideration has been given
to a possible use of the injection system for LINAC-30, which is in general similar to the 60 MeV electron linear
accelerator (LINAC-60) injector and which includes a low-voltage 25keV electron source and a five-cavity standing-
wave buncher. Two possible configurations of the upgraded accelerator have been considered. Schematically, they
can be represented as follows: 1) a new injector and a long section (4.41 m) of the basic accelerating channel; 2) a new
injector, a short (0.83 m) section (section N 1) currently operating at a retarded phase velocity of the wave, and a
long section (section N 2). Numerical modelling of particle dynamics in the accelerating channel has been performed
for the two cases. Based on the results obtained, assumptions are made as to the most optimum configuration of the
upgraded accelerator.
PACS: 29.20Ej
1. INTRODUCTION
One of the main objectives of the current LINAC-
30 upgrading program is to reduce the energy inho-
mogeneity of the accelerated beam. This is neces-
sary, first of all, for improving the efficiency of near-
threshold nuclear-physical experimentation at the ac-
celerator, when it is of importance to provide the
highest electron density on the working target in a
narrow energy range. An important task is also to
reduce the beam losses due to the energy spread
during beam formation and transport with an aim
to improve the radiation environment in the whole
accelerator-physical complex. This is of particular
importance when the accelerator is operated at maxi-
mum current conditions (∼100 µA) for supporting all
nuclear-physics and radiation programs. From gen-
eral physical considerations and operational experi-
ence of the basic facility LINAC-30, it appears pos-
sible to solve successfully the assigned tasks and to
reduce the energy spread (half-width of the spectrum)
to less than 5% for the accelerator operation under
steady-state conditions only upon an essential im-
provement in the conditions of electron bunch forma-
tion and upon attaining small phase widths (∼15◦).
This can be provided only with radical improvement
of the injector system. Another mandatory require-
ment here is an accurate adjustment of the microwave
power supply system of the sections and the mini-
mization of amplitude-phase instabilities due to pulse
modulator imperfection of klystrons (i.e., obtaining
small-front modulating voltage impulses of klystrons
with small amplitude fluctuations of no more than
1% within a pulse and from pulse to pulse).
2. CALCULATION OF DYNAMICS OF
PARTICLES IN THE LINAC-30 WITH A
VARIOUS CONFIGURATION OF
ACCELERATING STRUCTURES
The paper deals with possible ways of improving the
injector system of the accelerator LINAC-30. As a
variant of LINAC-30 modernization (as an alterna-
tive to the traditional method of using a two- or
three-cavity prebuncher), consideration can be given
to the device similar on the whole to the injector of
the linac LINAC-60 [1], which includes a low-voltage
(25 keV ) electron source and a 5-cavity standing-
wave buncher. The main rated parameters of one of
the modifications of this injector (according to the
data of the designers of the ”Accelerator” Complex
NNC KIPT) are given in Table 1.
Table 1. The main rated parameters of
one of the modifications of this injector
Gun current, A 1.1
Beam current, A 0.89
Bunch repetition
frequency, MHz 2797.15
Microwave power, MW 1.5
Phase extent (for 70%
of particles), degrees 14.7
Energy spectrum width (for 70%
of particles), % 4.4
Peak energy of the spectrum, keV 970
We have considered two possible variants of
LINAC-30 upgrading, which can be presented
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2009, N5.
Series: Nuclear Physics Investigations (52), p.141-146.
141
schematically as follows: - a new injector and a long
section (4.41 m) of the main accelerating channel; - a
new injector, a short (0.83 m) section with a reduced
phase velocity of the wave, and a long section.
In the second case, the microwave power supply is
provided by two klystrons KIU-12AM with the use of
a universal controlled waveguide system that can pro-
vide the serial feed regime for the two sections from
one klystron, the split-feed regime of the sections and
the regime of power summation at the input of the
second section. The process of steady longitudinal in-
teraction of the electron beam with a travelling wave
was modeled on the basis of the nonlinear theory for
the traveling-wave tube.
The simplest mathematical approximation vari-
ant, earlier described by Masunov [2], has been cho-
sen, according to which the average electron bunch
energy is determined on the assumption that a pre-
bunched electron beam with the bunch phase extent
of no more than 50◦ is injected into the waveguide
section. In our case this requirement is fulfilled with
a safety margin.
Below we give a nonlinear self-consistent set of
differential equations, which describe the process dy-
namics. The set was solved numerically with the use
of the FORTRAN programming language involving
the universal IMSL program package.
d
dx
U(x) = A(x) · cos(ϕ(x)) ,
d
dx
A(x) = −Pα ·A(x)− J0 ·m · cos(ϕ(x)) , (1)
d
dx
ϕ(x) = 2π·[ 1
βW
− U(x)√
U(x)2 − 1
]+
J0 ·m
A(x)
·sin(ϕ(x)) ,
where:
U(x) - average energy of the electron bunch
in units m0c
2 ( m0c
2 = 0.511 MeV );
x = z/λ0 - dimensionless distance;
z - longitudinal coordinate of the bunch;
λ0 - free-space wavelength;
Pα - field attenuation within the wavelength;
ϕ(x) - phase of bunches in relation to the total
self-consistent field;
βW = γW
c - relative phase velocity of the wave
in the section (c - speed of light);
A(x) = e·λ0·E(x)
m0c2 - dimensionless amplitude of
the total self-consistent field;
m = e·Rsλ2
0·I1
4m0c2 - current load factor ;
J0 - pulsed beam current;
Rs - series impedance of the structure;
I1 ∼ 2 - dimensionless 1st harmonic amplitude
of current for electron bunches of phase extent.
The results of the LINAC-30 performance analy-
sis for the two variants of upgrading through the use
of a new injector system are presented below.
3. USE OF THE NEW INJECTOR
SYSTEM WITH REFERENCE SECTION
OF THE LINAC-30
This variant 1 implies the electron bunch injection
from the injector output to the standard LINAC-30
section of length L = 4.41 m. It is the constant-
structure section with radial cuts of diaphragms
(Rn = 635 Om/cm2, the field attenuation being α =
6.8 × 10−4 cm−1). The dynamics and phase-energy
characteristics of the electron beam were calculated
for the zero and optimum current values. The input
beam parameters were conditionally chosen to be the
same for the both cases (U0 = 0.97 MeV ). The opti-
mum current is taken to mean its such value, at which
the highest beam energy (the derivative with respect
to z is zero) at a given accelerating field intensity E0
is attained at the end of the section. To calculate the
optimum current, we use the equation of point bunch
energy gain in the relativistic approximation
∆U(z) =
E0 · (1− e−α·z) · cos(ϕ)
α
−
−Rs · J
2
· α · z − 1 + e−α·z
α2
. (2)
At z = L and ∆U(z) = 0 , we have
Jlim =
2α · E0
Rs
· 1− e−α·L
α · L− 1 + e−α·L ; Jop =
Jlim
2
· δ .
(3)
Were Jlim is limiting current on the section. The
coefficient δ is dependent on the parameters of the
section and, in our case, δ ≈ 0.9 (if α = 0, then
δ = 1, i.e., only in the absence of attenuation the op-
timum current is equal to 0.5 of the limiting current).
Longitudinal coordinate z, cm
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.1. Beam energy dependence of the longitudinal
coordinates: curve 1 - for J = 0, curve 2 - for
J = Jop cross-hatching curves shows the dependence
U(z) calculated by the formula (2) in the relativistic
assumption
Figure 1 shows the average bunch energy in the ac-
celerating section as a function of the longitudinal
coordinate at the initial energy U0 = 0.97 MeV ,
the field intensity E0 = 90 kV/cm (E0 =
√
Rs · P0,
142
P0 = 12.756 MW ) and the initial phase of injec-
tion ϕ0 = 64◦. Curve 1 corresponds to the zero
beam current, and curve 2 - to the optimum current
Jop = 0.5502 A. Figure 2 shows the bunch phase
relative to the external field of the generator (curve
1) and to the total self-consistent field of both the
generator and the beam (curve 2) versus the longitu-
dinal coordinate at the same initial phase of injection.
Longitudinal coordinate z, cm
P
h
a
s
e
o
f
b
u
n
c
h
e
s
ϕ
,
d
e
g
Fig.2. Dependence of the bunches phase from the
generator field (curve 1) and total self-consistent
field of generator and electron beam (curve 2) from
longitudinal coordinate.
Figure 3 illustrates the average bunch energy
at the accelerating section output as a func-
tion of the injection phase at the same ini-
tial conditions for both the zero (curve 1)
and optimum (curve 2) beam current values.
Entering phase of bunches ϕ0, deg
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.3. Dependence of the bunch energy from injec-
tion phase: curve 1 - for J = 0, curve 2 - for J = Jop
As it follows from the data in Figs. 1 and 2, irrespec-
tive of a considerable phase slipping of bunches at
the beginning of the section, their average energy is
little different from the limiting values calculated by
formula (2), which describes the acceleration process
in the relativistic treatment of the problem. The
presence of flat regions on the curves of Fig. 3 in a
wide range of injection entrance angles demonstrates
practically ideal forming properties of this combi-
nation of accelerating components, which appears
weakly sensitive to amplitude-phase instabilities in
the microwave power supply system. In this case
one should expect the occurrence of most favorable
conditions for attaining a low electron-beam energy
spread at the output of the accelerator. The dis-
advantage of this variant of LINAC-30 upgrading is
the presence of some limitations (on account of using
one klystron) in achieving higher levels of beam en-
ergy and power, this essentially restricting possible
use of the accelerator in different nuclear-physics and
application programs.
4. USE OF THE NEW INJECTOR
SYSTEM WITH SHORT AND
REFERENCE SECTION OF THE
LINAC-30
In this case (variant 2) we assume to keep the exist-
ing accelerating system of LINAC-30 (long and short
accelerating sections) and to inject the beam from a
new injector into the short section, which will be op-
erated under usual temperature conditions providing
βW = 1 and will play the part of an additional accel-
erating section. By this variant, the system of uni-
versal microwave power supply of the two sections is
also retained. Its circuit is supplemented with a direc-
tional power coupler to energize the 5-cavity bunch-
ing facility of the new injector from the first klystron.
The process of a steady-state longitudinal interaction
of electron bunches with the travelling wave was mod-
elled for three possible variants of feeding the accel-
erating sections at optimum current conditions. The
main initial data for modelling are given in Table 2.
Table 2. ∗-Serial feed regime (µ = 1);
∗∗-Split-feed regime (µ = 0);
∗ ∗ ∗-Combined power regime (µ ≈ 0.5).
∗ ∗∗ ∗ ∗ ∗
µ = 1 µ = 0 µ ≈ 0.5
Section 1 field,
E01, kV/cm 90 90 90
Section 2 field,
E02, kV/cm 72.77 92.6 114.03
Optimum beam
current, Jop, A 0.4449 0.5661 0.6971
(The tabulated data correspond to the klystron
output power Pk1 ≈ 14.9 MW with allowance for
∼ 1.5 MW to energize the 5-cavity buncher of the
injector, and Pk2 ≈ 13.5 MW ). The modelling re-
sults are presented in the plots (Figs. 4 to 9).
The bunch energy in section 1 as a function of
the longitudinal coordinate is shown in Fig. 4 for
the regime of serial microwave feed of the sections.
With the section length of 83 cm and a current of
∼ 0.4 A the conditions appear to be far from op-
143
timum, and this function is practically linear. For
the same regime, fig.5 shows the phase as a func-
tion of the distance travelled in section 1. It can
be seen that an intense slipping of bunches relative
to the self-consistent field, which characterizes the
process of bunch formation, takes place. Figure 6
shows the beam energy at the output of section 1
versus the phase of input bunches. As it can be
seen from the figure, this is not such an ideal curve
as it was obtained in the description of variant 1
Longitudinal coordinate z, cm
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
1
,
M
e
V
Fig.4. Dependence of the bunch energy in section
1 from longitudinal coordinate. (E01 = 90 kV/cm,
J ≈ 0.44 A)
of LINAC-30 upgrading (see Fig. 3). However, there
are the phase sections on the curve that encourage to
optimization of the working parameters of the beam.
Longitudinal coordinate z,cm
P
h
a
s
e
o
f
b
u
n
c
h
e
s
ϕ
,
d
e
g
Fig.5. Dependence of the bunches phase from lon-
gitudinal coordinate. (E01 = 90 kV/cm, J ≈ 0.44 A)
Figure 7 shows the beam energy in section 2 as a
function of the longitudinal coordinate of the beam
motion. The same figure shows the function U2rel
calculated by formula (2) in the relativistic approxi-
mation. As it is obvious from the figure, the curves
are coincident. Figure 8 shows the phase depen-
dence on the longitudinal coordinate in section 2. It
is seen that at the initial energy U02 ≈ 7.7 MeV
an insignificant phase slipping of bunches takes
place for the optimum injection phase ϕ02 ≈ 6.0◦.
Entering phase of bunches ϕ, deg
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.6. Dependence of the beam energy at the
output of section 1 from phase of input bunches.
(E01 = 90 kV/cm, J ≈ 0.44 A)
Longitudinal coordinate z, cm
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.7. Dependence of the beam energy in section 2
from the longitudinal coordinate
Longitudinal coordinate z, cm
P
h
a
s
e
o
f
b
u
n
c
h
e
s
ϕ
,
d
e
g
Fig.8. Dependence of the phase from the longitudi-
nal coordinate in section 2
Figure 9 shows the beam energy at the output of sec-
tion 2 as a function of the initial phase of bunches,
144
this function being one of the main characteristics
of the accelerator. It will be recalled that all the
above-described dependences were obtained for the
regime of serial microwave feed of the sections, i.e.,
at the initial conditions given in column 1 of Table
2. In what follows we shall not describe in detail
all the dependences for other power supply regimes
for the sections. They are alike, in principle. We
shall dwell only on the main characteristics and their
comparison.
Entering phase of bunches ϕ, deg
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.9. Dependence of the beam energy at the output
of section 2 from the initial phase of bunches
For comparison, Fig. 10 presents the beam energy
versus the phase of input bunches for all three regimes
of microwave feed of the sections at initial conditions
given in Table 2. Curve 1 corresponds to the serial
feed regime, curve 2 - split-feed regime, and curve 3 -
power summation. It can be seen that the optimum
phases for all three regimes are practically the same
(∼ 7◦). The curves are sinusoidal in shape, this being
characteristic of a strongly relativistic case.
Entering phase of bunches ϕ, deg
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
Fig.10. Dependence of the beam energy from the
phase of input bunches: curve 1 - the serial feed
regime; curve 2 - the split-feed regime; curve 3 -
power summation regime
Figure 11 displays load characteristics of the accel-
erator LINAC-30 with a new injector system at all
possible regimes of microwave feed of the sections,
which were calculated by the given technique in the
current range between 0 and 1A. Graphic pairs 1, 2, 3
are, respectively, for serial feed, split feed and power
summation. The straight lines represent the energy
dependences, and the curves show the average beam
power versus current (at current pulse time τ =
1.7 µs and pulse repetition frequency F = 100 Hz).
Current of an electron beam I, A
E
n
e
rg
y
o
f
b
u
n
c
h
e
s
U
,
M
e
V
M
e
a
n
p
o
w
e
r
o
f
a
n
e
le
c
tr
o
n
b
e
a
m
,
K
W
Fig.11. Load characteristics of the LINAC-30 at
all possible regimes of microwave feed of the sections
(red lines - energy of bunches, blue lines - power of
an electron beam): curve 1 - for serial feed regime;
curve 2 - the split-feed regime; curve 3 - power
summation regime. The straight lines represent
the energy dependences; curves show the average
beam power versus current (τ = 1.7 µs, F = 100 Hz)
The realization of the second variant of LINAC-30
upgrading will provide a substantial improvement in
the beam parameters at all modes of operation due
to a more perfect injection system. However, an ulti-
mate energy increase at the power summation regime
(up to 50 MeV ) is practically impossible. As oper-
ation experiment with the universal power system
of the sections has shown, there are the limitations
connected with an insufficient electrical strength of
both the waveguide elements and the section. The
generation of power above 17MW at the input of
section 2 seems to be very problematic. At the same
time, at operation even in the most economy mode
of serial feed of the two accelerator sections from one
klystron at a pulsed current of ∼ 0.5 A, the electron
beam energy may attain ∼ 20 MeV (at zero current
∼ 40 MeV ). That is to say, in this case a rather wide
range of nuclear-physics and applied research can be
successfully performed at the accelerator.
5. CONCLUSION
From the carried out examinations it is possible to
draw a deduction, that each of probable configura-
tions of modernized accelerator LINAC-30 has the
advantages and shortages. In case of injection of a
electron beam immediately in reference section it is
necessary to expect making of optimum requirements
for deriving small energy scatters in an electron beam
145
on an exit of the accelerator. Essential shortages of
this variant of modernization, rather low levels of an
energy and a potency of a electron beam are, that
essentially restricts possibilities of application of the
accelerator in various nuclear - physical and applied
programs. Embodying of the second variant of mod-
ernization LINAC-30 also will allow to improve con-
siderably parameters of an electron beam in all oper-
ating modes for the account of more perfect type of
an injector system. However, to receive limiting raise
of an energy in condition of addition of a potency (up
to 50 MeV ) practically is not possible in connection
with poor electrical strength waveguide devices and
section.
Thus it is necessary to note, that the universal
microwave power supply system of both section can
worsen some parameters of an electron beam ow-
ing to presence in it of transients. Thus, the fi-
nal solution about a configuration of the modernized
accelerator can be accepted radiating from pri-
ority the posed physical problems and available
engineering possibilities.
References
1. M.I. Ayzatskiy, P.G. Gurtovenko, V.F. Zhiglo,
E.Yu. Kramarenko, V.M. Kodyakov, V.A. Kush-
nir, V.V. Mytrochenko and oth. Compact elec-
tron injector for s-band linac // Problems of
Atomic Science and Technology. Series ”Nuclear
Physics Investigations. 2008, v.3, p.68-72.
2. E.S. Masunov New a computational method of
dynamics of high-current bundles in LAE. //
Problems of Atomic Science and Technology.
Series ”Nuclear Physics Investigations. 1977,
v.2(5), p.54-56.
АНАЛИЗ ХАРАКТЕРИСТИК ЛУЭ-30 С НОВОЙ ИНЖЕКТОРНОЙ СИСТЕМОЙ
С.П. Гоков, Л.А. Махненко, И.В. Ходак, О.А. Шопен
Данная работа посвящена вопросам модернизации линейного ускорителя электронов (ЛУЭ-30) с
целью получения оптимальных спектральных характеристик пучка. Как один из вариантов рекон-
струкции ускорителя ЛУЭ-30 рассмотрена возможность использования в качестве инжекторной систе-
мы для него устройство, в целом подобное инжектору ЛУЭ-60, включающее низковольтный источник
электронов 25 кэВ и 5-резонаторный группирователь на стоячей волне. Рассмотрены две возможные
конфигурации модернизированного ускорителя, схемы которых можно представить как: новый ин-
жектор и длинная секция (4.41м) основного ускоряющего тракта; новый инжектор, короткая (0.83м)
секция (секция N1), работающая в настоящее время с пониженной фазовой скоростью волны, и длин-
ная секция (секция N2). Для обоих случаев проведено численное моделирование динамики частиц в
ускоряющем тракте. На основе полученных результатов высказываются предположения о наиболее
оптимальной конфигурации модернизированного ускорителя.
АНАЛIЗ ХАРАКТЕРИСТИК ЛПЕ-30 З НОВОЮ IНЖЕКТОРНОЮ СИСТЕМОЮ
С.П. Гоков, Л.О. Махненко, I.В. Ходак, О.О. Шопен
Дана робота присвячена питанням модернiзацiї лiнiйного прискорювача електронiв (ЛПЕ-30) з ме-
тою отримання оптимальних спектральних характеристик пучка. Як один з варiантiв реконструкцiї
прискорювача ЛПЕ-30 розглянута можливiсть використання в якостi iнжекторної системи для нього
пристрiй, в цiлому подiбний iнжектору ЛПЕ-60, який включає в себе низьковольтне джерело элек-
тронiв 25 кеВ i 5-резонаторний групирувальник на стоячiй хвилi. Розглянутi двi можливi конфiгурацiї
модернiзованого прискорювача, схеми яких можна представити як: новий iнжектор та довга секцiя
(4.41 м)основного прискорюючого тракту; новий iнжектор, коротка (0.83м) секцiя (секцiя N1), яка
працює в даний час з пониженою фазовою швидкiстюю хвилi, та довга секцiя (секцiя N2). Для обох
випадкiв проведено чисельне моделювання динамiки часток в прискорюючому трактi. На основi отри-
маних результатiв висловлюються припущення про найбiльш оптимальну конфигурацiю модернiзова-
ного прискорювача.
146
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