Design of linear induction electron accelerator LIA-R
A design of linear induction electron accelerator LIA-R meant for generation of bremsstrahlung pulse of duration ~ 50 ns at half maximum is presented. As well as a facility LIA-10M the accelerator consists of an injector and 16 standard acceleration modules. As an injector it is supposed to use a...
Збережено в:
| Дата: | 2006 |
|---|---|
| Автори: | , , |
| Формат: | Стаття |
| Мова: | English |
| Опубліковано: |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2006
|
| Назва видання: | Вопросы атомной науки и техники |
| Теми: | |
| Онлайн доступ: | http://dspace.nbuv.gov.ua/handle/123456789/78698 |
| 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: | Design of linear induction electron accelerator LIA-R / V.S. Gordeev, G.А. Myskov, Е.С. Mikhailov // Вопросы атомной науки и техники. — 2006. — № 2. — С. 40-42. — Бібліогр.: 6 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-78698 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-786982018-03-21T13:04:28Z Design of linear induction electron accelerator LIA-R Gordeev, V.S. Myskov, G.А. Mikhailov, Е.С. Линейные ускорители заряженных частиц A design of linear induction electron accelerator LIA-R meant for generation of bremsstrahlung pulse of duration ~ 50 ns at half maximum is presented. As well as a facility LIA-10M the accelerator consists of an injector and 16 standard acceleration modules. As an injector it is supposed to use a modification of STRAUS-R accelerator developed on the basis of five-cascade double stepped forming line (DSFL) of diameter 1.2 m with water insulation. Inductors will be made on the basis of four-cascade DSFL of diameter 1 m. It is expected to accelerate the electron beam up to the energy ~30 MeV at the acceleration rate ~1 MeV/m. Представлен проект линейного индукционного ускорителя электронов ЛИУ-Р, предназначенного для генерации импульса тормозного излучения длительностью ∼ 50 нс. Как и установка ЛИУ-10М ускоритель состоит из инжектора и 16 типовых ускорительных модулей. В качестве инжектора предполагается использовать модификацию ускорителя СТРАУС-Р, разработанного на базе пятикаскадной двойной ступенчатой формирующей линии (ДСФЛ) диаметром 1.2 м с водяной изоляцией. Индукторы будут выполнены на базе четырехкаскадной ДСФЛ диаметром 1 м. Электронный пучок предполагается ускорять до энергии ∼30 МэВ при темпе ускорения ∼ 1 МэВ/м. Представлено проект лінійного індукційного прискорювача електронів ЛІП-Р, призначеного для генерації імпульсу гальмового випромінювання тривалістю ∼ 50 нс. Як і установка ЛІП-10М прискорювач складається з інжектора і 16 типових прискорювальних модулів. Як інжектор передбачається використати модифікацію прискорювача СТРАУС-Р, розробленого на базі п’ятикаскадної подвійної східчастої формуючої лінії (ПСФЛ) діаметром 1,2 м з водяною ізоляцією. Індуктори будуть виконані на базі чотирьохкаскадної ПСФЛ діаметром 1 м. Електронний пучок передбачається прискорювати до енергії 30 МеВ при темпі прискорення 1 МеВ/м. 2006 Article Design of linear induction electron accelerator LIA-R / V.S. Gordeev, G.А. Myskov, Е.С. Mikhailov // Вопросы атомной науки и техники. — 2006. — № 2. — С. 40-42. — Бібліогр.: 6 назв. — англ. 1562-6016 PACS: 29.17.+w; 84.70.+p http://dspace.nbuv.gov.ua/handle/123456789/78698 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 |
Линейные ускорители заряженных частиц Линейные ускорители заряженных частиц |
| spellingShingle |
Линейные ускорители заряженных частиц Линейные ускорители заряженных частиц Gordeev, V.S. Myskov, G.А. Mikhailov, Е.С. Design of linear induction electron accelerator LIA-R Вопросы атомной науки и техники |
| description |
A design of linear induction electron accelerator LIA-R meant for generation of bremsstrahlung pulse of duration
~ 50 ns at half maximum is presented. As well as a facility LIA-10M the accelerator consists of an injector and
16 standard acceleration modules. As an injector it is supposed to use a modification of STRAUS-R accelerator developed
on the basis of five-cascade double stepped forming line (DSFL) of diameter 1.2 m with water insulation.
Inductors will be made on the basis of four-cascade DSFL of diameter 1 m. It is expected to accelerate the electron
beam up to the energy ~30 MeV at the acceleration rate ~1 MeV/m. |
| format |
Article |
| author |
Gordeev, V.S. Myskov, G.А. Mikhailov, Е.С. |
| author_facet |
Gordeev, V.S. Myskov, G.А. Mikhailov, Е.С. |
| author_sort |
Gordeev, V.S. |
| title |
Design of linear induction electron accelerator LIA-R |
| title_short |
Design of linear induction electron accelerator LIA-R |
| title_full |
Design of linear induction electron accelerator LIA-R |
| title_fullStr |
Design of linear induction electron accelerator LIA-R |
| title_full_unstemmed |
Design of linear induction electron accelerator LIA-R |
| title_sort |
design of linear induction electron accelerator lia-r |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2006 |
| topic_facet |
Линейные ускорители заряженных частиц |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/78698 |
| citation_txt |
Design of linear induction electron accelerator LIA-R / V.S. Gordeev, G.А. Myskov, Е.С. Mikhailov // Вопросы атомной науки и техники. — 2006. — № 2. — С. 40-42. — Бібліогр.: 6 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT gordeevvs designoflinearinductionelectronacceleratorliar AT myskovga designoflinearinductionelectronacceleratorliar AT mikhailoves designoflinearinductionelectronacceleratorliar |
| first_indexed |
2025-07-06T02:46:10Z |
| last_indexed |
2025-07-06T02:46:10Z |
| _version_ |
1836863949241319424 |
| fulltext |
DESIGN OF LINEAR INDUCTION ELECTRON ACCELERATOR LIA-R
V.S. Gordeev, G.А. Мyskov, Е.С. Мikhailov
Russian Federal Nuclear Center – All-Russian Scientific Research
Institute of Experimental Physics (RFNC-VNIIEF)
607188, Russia, Sarov, Mira avenue, 37
E-mail: gordeev@expd.vniief.ru
A design of linear induction electron accelerator LIA-R meant for generation of bremsstrahlung pulse of dura-
tion ~ 50 ns at half maximum is presented. As well as a facility LIA-10M the accelerator consists of an injector and
16 standard acceleration modules. As an injector it is supposed to use a modification of STRAUS-R accelerator de-
veloped on the basis of five-cascade double stepped forming line (DSFL) of diameter 1.2 m with water insulation.
Inductors will be made on the basis of four-cascade DSFL of diameter 1 m. It is expected to accelerate the electron
beam up to the energy ~30 MeV at the acceleration rate ~1 MeV/m.
PACS: 29.17.+w; 84.70.+p
INTRODUCTION
Recently in many countries (the USA, Great Britain,
France, China, Russia) there have been conducted
works on developing of electron accelerators of differ-
ent type meant for X-ray imaging of fast processes and
capable to generate powerful bremsstrahlung radiation
pulses of length not more than 100 ns at focusing of
electron beam on the target to a spot with a diameter of
several mm and less. For this purpose accelerators of
various types are used. (LIA on the base of inductors
with ferromagnetic cores or metglass cores, accelerators
with employment of technology of inductive voltage
adder, linear high-frequency accelerators, direct-action
pulsed accelerators, ironless betatrons). The results of
works are covered in details in the scientific literature
(see, for example, review [1] and references presented).
One should pay attention to the fact that each labora-
tory participating in creation of such accelerators directs
its efforts, as a rule, to the facilities of special type. This
is explained by the fact that development of each such
accelerator is based upon employment of special tech-
nologies mastered in these laboratories whose practical
realization takes a lot of years and requires large materi-
al expenses.
For several decades RFNC-VNIIEF has been accu-
mulating a large experience of development and opera-
tion of ironless linear induction accelerators with induc-
tors on the basis of transmission lines with water insula-
tion [2,3]. The main units of accelerating system of such
facilities are: an injector and a series of one-type accel-
eration modules (inductors) installed in turn, where an
electron beam is formed and accelerated, a beam trans-
portation track to the site of experiments, and, if neces-
sary, a focusing unit. To prevent the beam radial expan-
sion under the effect of volume charge forces in the
near-axial area along the whole length of the accelerator
a pulse uniform longitudinal magnetic field is created.
In the accelerators LIA-10, LIA-10M and LIA-30
there are formed annular electron beams of diameter
60…200 mm with current of 30…100 kA which at
boundary acceleration energy of 14…40 MeV generate
powerful pulses of bremsstrahlung radiation with rela-
tively short duration of 10…20 ns. Magnetic field in-
duction in the accelerating channel is 0.5…0.6 T.
Accelerators of such a type can be used for the pur-
poses of fast processes studying. Below a design of
powerful X-ray accelerator LIA-R is briefly described.
1. INDUCTOR LIA-R
As a result of analysis of results of a large series of
calculations to form the pulses of accelerating voltage in
the facility LIA-R there were selected inductors on the
basis of stepped forming lines made with the use of
cylindrical coaxial lines with water insulation [2,4]. The
inductor is designed according to the circuit of four-cas-
cade double stepped forming line (DSFL) presented in
Fig.1.
Fig.1. Circuit diagram of inductor LIA-R
When switch S1 is closed at the output of inductor
charged up to the voltage U0 beginning from the time
point T0 there are formed voltage pulses of alternating
polarity of 2T0 duration that have, ideally, a square
shape. Here T0 is an electric length of individual cas-
cade. The second voltage pulse is a working one. At
correlation of impedances Z1:Z2:Z3:Z4= 1:3:6:2 such a
circuit possesses, ideally, 100% efficiency and in the
matched mode of operation it provides a two-fold in-
crease of the output voltage as compared to the charging
voltage of the line and in the idle-running mode – a
four-fold increase. The given circuit was earlier success-
fully used at development of 16 inductors of accelerator
LIA-10M [4].
Fig.2 presents an inductor construction diagram.
DSFL is formed by the coaxial cylindrical lines 1…
4 with water insulation arranged subsequently over the
radius in the case Ø1 m and 1.3 m in length. The output
impedance of DSFL is 7 Ohm. On the outer diameter of
DSFL a triggered multi-channel switch is mounted
formed by 18 gas-filled spark gaps 5. Accelerating tube
8 is made as a polyethylene tube and a sectioned insula-
tor mounted inside, between them a tubular layer of wa-
ter solution NaCl is placed. The space between the ac-
celerating tube, polyethylene diaphragm 6 and metallic
cone 9 is filled by transformer oil. The full axial size of
inductor is ~1.8 m.
___________________________________________________________
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2006. № 2.
Series: Nuclear Physics Investigations (46), p.40-42.
40
mailto:gordeev@expd.vniief.ru
Fig.2. Construction diagram of inductor LIA-R
The electron beam with diameter ≤ 20 mm propa-
gates in the paraxial vacuum channel Ø60 mm. With the
aid of solenoid 7 in the vacuum channel when accelerat-
ing the beam there is formed a longitudinal field that is
rather uniform by length with induction of 1.5…2 T.
DSFL will be charged up to the voltage ∼500 kV by a
six-cascade Marx generator with output capacity 135 nF
using in every cascade two condensers IEPM-100-0.4.
2. INJECTOR LIA-R
Selection of circuit and construction diagrams for
the injector depended mostly on selection of corre-
sponding diagrams for inductors of facility LIA-R. As a
result of analysis of different variants for a high-voltage
pulse shaping in the injector there was selected a circuit
diagram of five-cascade DSFL (Fig.3) which possesses,
ideally, 100% efficiency at correlation of impedances
Z1:Z2:Z3:Z4:Z5= 1:3:3.75:1.25:15.
In the matched mode of operation the voltage at the
output of DSFL grows by a factor of three as compared
to the charging line voltage, and in the idle-running
mode − by a factor of six. The given circuit was earlier
successfully used when developing accelerators
STRAUS, STRAUS-2 and LIA-10M injector [4].
Fig. 3. Circuit diagram of inductor LIA-R
The simplified injector construction diagram is giv-
en in Fig.4. DSFL is formed by cylindrical coaxial lines
with water insulation 1…5 placed in the case Ø1.2 m.
The output impedance of DSFL is 18 Ohm. On the outer
case diameter there was mounted a triggered multi-
channel switch formed by 20 gas-filled spark gaps 6.
Accelerating tube 9 is similar in design to the accelerat-
ing inductor tube. The space between the accelerating
tube, polyethylene diaphragm 7 and cone 12 is filled by
transformer oil.
Fig.4. Construction diagram of injector LIA-R
In the inner vacuum volume of the accelerating tube
there are located cathode support 10 and a cylindrical
cathode, whose emitting edge is placed in output cham-
ber 11. When triggering switch 6 at the output of DSFL
there are formed pulses of altering polarity voltage. The
second pulse is working and the first one is cut off from
the accelerating tube by one-channel triggered prepulse
gas-filled gap 8. The required distribution of the mag-
netic field in the area of vacuum diode is developed
with the aid of pulse solenoids 12 and 13. The full axial
size of injector is ∼ 4.5 m.
DSFL will be charged up to the working voltage ≤
650 kV for the time 0.8 μs by 8-cascade Marx generator
with output capacity 100 nF using in every cascade two
condensers IEPM-100-0.4.
3. ACCELERATING SYSTEM LIA-R
In the developed design the accelerating system
LIA-R is to be made as a part of the injector, 16 stan-
dard accelerating modules, the electron beam trans-
portation track and the output focusing unit. By its ap-
pearance and composition the accelerating system LIA-
R will be closely similar to an analogous accelerator
LIA-10M system, but it differs in increased axial di-
mensions of the injector and inductors.
A specific feature of accelerator LIA-R as compared
to the earlier developed ironless LIA is the necessity to
focus the beam at the output of the facility to a small-
size spot. Taking into account a circuit (accepted in such
type facilities) of injection, acceleration and transport of
the beam in the uniform longitudinal magnetic field
such an operating condition imposes limits on the maxi-
mum diameter of the injected beam and requires obtain-
ing of electrons with minimum transverse impulse at the
facility output. In LIA-R the beam diameter should not
exceed 20 mm.
Besides, according to the terms of application LIA-R
can have a much higher (up to 100 ns) pulse duration. It
is shown that at accelerator implementation on the basis
of above-named circuit designs the optimal half-height
duration of bremsstrahlung radiation is 45…50 ns at
current pulse duration of ∼60 ns. This was a reason for
refuse to employ the radial lines in inductors. A signifi-
cant interest should be also paid to the growth of the fa-
cility operation reliability and to the accelerating system
precise adjustment.
According to the results of numerical simulation the
injector must provide formation of the electron beam
with current of 10…20 kA at the outer diameter 10…
20 mm and the boundary electron energy of 3…
3.3 MeV (Fig.5,a). Accelerating voltage pulse duration
on the level of 0.5 from the amplitude value is 60 ns, on
the level of 0.9…50 ns [5].
The beam formed in the injector will be accelerated
in the vacuum channel of diameter 60 mm at induction
of longitudinal magnetic field of 1.5…2 T. At the output
of each inductor there should be generated a pulse of ac-
celerating voltage of the amplitude of 1.75…1.65 MV
(at current of 10…20 kA) with duration on the level
0.5 from the amplitude value of 63 ns, on the level
0.9…43 ns (Fig.5,b). A possibility exists for changing
the amplitude of the accelerating voltage (within certain
limits) through varying the inductor charging voltage
and resistance of electrolytic load of the accelerating
tube.
At the accelerator output the diameter of the electron
beam with the maximum energy of particles of about
30 MeV will decrease ~4 times at the length of ~1 m
through the use of intensively growing magnetic field
___________________________________________________________
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2006. № 2.
Series: Nuclear Physics Investigations (46), p.40-42.
40
with maximum induction of ~30 T. According to the
calculations the bremsstrahlung dose at a distance of
1 m from the target should be from 2000 to 4000 R.
The advantage of the proposed variant of radiogra-
phy accelerator is a possibility to obtain rather large
pulse currents and bremsstrahlung doses and, what is
more important for installation of LIA-R, a weak depen-
dence of the sizes of focus spot on the electron energy at
the accelerator output. Disadvantages are a relatively
large energy store of the capacitor bank used for devel-
opment of pulsed magnetic field in the accelerator.
а
-3000
-2000
-1000
0
1000
2000
3000
4000
90 120 150 180 210 240 270
t, нс
V,
к
В
b
-1500
-1000
-500
0
500
1000
1500
2000
2500
0 20 40 60 80 100 120 140 160 180 200
t, нс
V,
к
В
Fig.5. Calculation pulse shapes of the accelerating volt-
age of injector (a) and inductor (b)
The developed design is realized by several stages.
At the first stage in 2003 an injector prototype –
STRAUS-R pulse electron accelerator was created [6].
It is used as an independent radiography accelerator and
provides for a focus spot ≤ 4 mm in diameter on the tar-
get at the maximum X-ray dose of 27 R at a distance of
1m from the output flange. The boundary electron ener-
gy is 3.0…3.5 МeV, the beam current is ≤ 60 kА and
the bremsstrahlung radiation pulse duration is ≤50 ns.
Experimentally determined accelerator characteristics
correspond to the design parameters.
At present the development of LIA-R mock-up with
acceleration energy of ~10 MeV as a part of the injec-
tor, four acceleration modules, the beam transportation
track and the output focusing is being finished. Experi-
mental results obtained here will be taken into account
when creating a full-scale accelerator LIA-R with accel-
eration energy of ~30 MeV.
REFERENCES
1. C. Ekdahl. Modern Electron Accelerators for Radio-
graphy // IEEE Trans. on Plasma Science. 2002,
v.30, №1, p.254-261.
2. V.S. Bosamykin, А.I. Gerasimov, V.S. Gordeev.
Ironless linear induction electron accelerators –
powerful generators of bremsstrahlung short pulses.
High Energy Densities. Collection of Proc. RFNC-
VNIIEF. Sarov. 1997, p.107-133.
3. M.A. Voinov, A.I. Gerasimov, V.S. Gordeev et al.
Complexes on the Basis of High-Current Linear In-
duction Accelerators and Pulsed Nuclear Reactors//
Problems of Atomic Science and Technology. Se-
ries: Nuclear Physics Investigations. 1999, №3(32),
p.82-84.
4. V.S. Gordeev, V.F. Basmanov, G.A. Myskov et al.
High-current pulsed electron accelerators based on
step-like forming lines // Problems of Atomic Sci-
ence and Technology. Series: Nuclear Physics In-
vestigations. 2001, №3(38), p.50-52.
5. V.S. Gordeev, E.S. Mikhailov, G.A. Myskov,
D.V. Laptev. Numerical simulation of the processes
of small-diameter high-current electron beam shap-
ing and injection // Problems of Atomic Science and
Technology. Series: Nuclear Physics Investigations.
2001, №5(39), p.33-35.
6. V.S. Gordeev, G.A. Myskov, V.F. Basmanov et al.
Pulsed Electron Accelerator STRAUS-R. Proc. of the
15th Intern. Conf. on High-Power Particle Beams,
BEAMS’2004. 2004, Saint-Petersburg, p.323-326.
ПРОЕКТ ЛИНЕЙНОГО ИНДУКЦИОННОГО УСКОРИТЕЛЯ ЭЛЕКТРОНОВ ЛИУ-Р
В.С. Гордеев, Г.А. Мысков, Е.С. Михайлов
Представлен проект линейного индукционного ускорителя электронов ЛИУ-Р, предназначенного для ге-
нерации импульса тормозного излучения длительностью ∼ 50 нс. Как и установка ЛИУ-10М ускоритель со-
стоит из инжектора и 16 типовых ускорительных модулей. В качестве инжектора предполагается использо-
вать модификацию ускорителя СТРАУС-Р, разработанного на базе пятикаскадной двойной ступенчатой
формирующей линии (ДСФЛ) диаметром 1.2 м с водяной изоляцией. Индукторы будут выполнены на базе
четырехкаскадной ДСФЛ диаметром 1 м. Электронный пучок предполагается ускорять до энергии ∼30 МэВ
при темпе ускорения ∼ 1 МэВ/м.
ПРОЕКТ ЛІНІЙНОГО ІНДУКЦІЙНОГО ПРИСКОРЮВАЧА ЕЛЕКТРОНІВ ЛІП-Р
В.С. Гордєєв, Г.А. Мисков, Є.С. Михайлов
Представлено проект лінійного індукційного прискорювача електронів ЛІП-Р, призначеного для
генерації імпульсу гальмового випромінювання тривалістю ∼ 50 нс. Як і установка ЛІП-10М прискорювач
складається з інжектора і 16 типових прискорювальних модулів. Як інжектор передбачається використати
модифікацію прискорювача СТРАУС-Р, розробленого на базі п’ятикаскадної подвійної східчастої
формуючої лінії (ПСФЛ) діаметром 1,2 м з водяною ізоляцією. Індуктори будуть виконані на базі
чотирьохкаскадної ПСФЛ діаметром 1 м. Електронний пучок передбачається прискорювати до енергії
30 МеВ при темпі прискорення 1 МеВ/м.
32
|