Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping
The rates of pumping hydrogen and nitrogen by the non-evaporable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector are investigated. The measurements at the temperature range 473…1300 K and pressures from 13 to 10⁻³ Pa were carried out. The highest pumping rates of hydr...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2022
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| Цитувати: | Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping / A.M. Aksonova, V.V. Belicov, S.A. Vdovin, P.L. Makhnenko, M.M. Pylypenko, A.P. Podolyak, E.I. Ponomarchuk, O.P. Svynarenko, V.I. Skibin // Problems of Atomic Science and Technology. — 2022. — № 1. — С. 46-50. — Бібліогр.: 9 назв. — англ. |
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irk-123456789-1958212023-12-07T12:50:40Z Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping Aksonova, A.M. Belicov, V.V. Vdovin, S.A. Makhnenko, P.L. Pylypenko, M.M. Podolyak, A.P. Ponomarchuk, E.I. Svynarenko, O.P. Skibin, V.I. Pure materials and vacuum technologies The rates of pumping hydrogen and nitrogen by the non-evaporable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector are investigated. The measurements at the temperature range 473…1300 K and pressures from 13 to 10⁻³ Pa were carried out. The highest pumping rates of hydrogen ((283±15) l/s) and nitrogen ((133±15) l/s) achieved at the temperature range 525…575 K and pressure from 13 to 10⁻³ Pa has been established. It is shown that the proposed non-evaporated getter Zr(86)-Al(14) provided the required operating pressure in the chamber of the plasma-ion injector of the linear proton accelerator and the minimum concentration of hydrogen, nitrogen, and other residual gases. Проведені виміри швидкостей відкачування водню і азоту в камері плазмово-іонного інжектора протонів з розташованим всередині неї для її додаткового відкачування гетером Zr(86)-Al(14), що не випаровується. Виміри проведені в інтервалі температур 473…1300 К і тисків 13…~ 10⁻³ Па. Установлені найбільші швидкості відкачування водню ((283±15) л/с) і азоту ((133±15) л/с), що досягаються в інтервалі температур 525…595 К і тисків 13…~ 10⁻³ Па. Показано, що запропонований гетер, що не випаровується, Zr(86)-Al(14) забезпечує необхідний робочий тиск у камері плазмово-іонного інжектора лінійного прискорювача протонів та мінімальну концентрацію водню, азоту та інших залишкових газів. Проведены измерения скоростей откачки водорода и азота в камере плазменно-ионного инжектора протонов с размещенным внутри нее неиспаряемым геттером Zr(86)-Al(14). Измерения проведены в интервале температур 473…1300 К и давлений 13…∼ 10⁻³ Па. Установлены наибольшие скорости откачки водорода ((283±15) л/с) и азота ((133±15) л/с), достигаемые в интервале температур 525…575 К и давлений 13…∼10⁻³ Па. Показано, что предложенный неиспаряемый геттер Zr(86)-Al(14) обеспечивает необходимое рабочее давление в камере плазменно-ионного инжектора линейного ускорителя протонов и минимальную концентрацию водорода, азота и других остаточных газов. 2022 Article Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping / A.M. Aksonova, V.V. Belicov, S.A. Vdovin, P.L. Makhnenko, M.M. Pylypenko, A.P. Podolyak, E.I. Ponomarchuk, O.P. Svynarenko, V.I. Skibin // Problems of Atomic Science and Technology. — 2022. — № 1. — С. 46-50. — Бібліогр.: 9 назв. — англ. 1562-6016 PACS: 81.05.-t, 07.30.-t DOI: https://doi.org/10.46813/2022-137-046 http://dspace.nbuv.gov.ua/handle/123456789/195821 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 |
Pure materials and vacuum technologies Pure materials and vacuum technologies |
| spellingShingle |
Pure materials and vacuum technologies Pure materials and vacuum technologies Aksonova, A.M. Belicov, V.V. Vdovin, S.A. Makhnenko, P.L. Pylypenko, M.M. Podolyak, A.P. Ponomarchuk, E.I. Svynarenko, O.P. Skibin, V.I. Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping Вопросы атомной науки и техники |
| description |
The rates of pumping hydrogen and nitrogen by the non-evaporable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector are investigated. The measurements at the temperature range 473…1300 K and pressures from 13 to 10⁻³ Pa were carried out. The highest pumping rates of hydrogen ((283±15) l/s) and nitrogen ((133±15) l/s) achieved at the temperature range 525…575 K and pressure from 13 to 10⁻³ Pa has been established. It is shown that the proposed non-evaporated getter Zr(86)-Al(14) provided the required operating pressure in the chamber of the plasma-ion injector of the linear proton accelerator and the minimum concentration of hydrogen, nitrogen, and other residual gases. |
| format |
Article |
| author |
Aksonova, A.M. Belicov, V.V. Vdovin, S.A. Makhnenko, P.L. Pylypenko, M.M. Podolyak, A.P. Ponomarchuk, E.I. Svynarenko, O.P. Skibin, V.I. |
| author_facet |
Aksonova, A.M. Belicov, V.V. Vdovin, S.A. Makhnenko, P.L. Pylypenko, M.M. Podolyak, A.P. Ponomarchuk, E.I. Svynarenko, O.P. Skibin, V.I. |
| author_sort |
Aksonova, A.M. |
| title |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| title_short |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| title_full |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| title_fullStr |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| title_full_unstemmed |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| title_sort |
application in a linear proton accelerator of a non-vaporizable zr(86)-al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2022 |
| topic_facet |
Pure materials and vacuum technologies |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/195821 |
| citation_txt |
Application in a linear proton accelerator of a non-vaporizable Zr(86)-Al(14) getter located inside the chamber of a plasma-ion proton injector for its additional pumping / A.M. Aksonova, V.V. Belicov, S.A. Vdovin, P.L. Makhnenko, M.M. Pylypenko, A.P. Podolyak, E.I. Ponomarchuk, O.P. Svynarenko, V.I. Skibin // Problems of Atomic Science and Technology. — 2022. — № 1. — С. 46-50. — Бібліогр.: 9 назв. — англ. |
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Вопросы атомной науки и техники |
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46 ISSN 1562-6016. ВАНТ. 2022. №1(137)
https://doi.org/10.46813/2022-137-046
APPLICATION IN A LINEAR PROTON ACCELERATOR
OF A NON-VAPORABLE Zr(86)-Al(14) GETTER LOCATED INSIDE
THE CHAMBER OF A PLASMA-ION PROTON INJECTOR
FOR ITS ADDITIONAL PUMPING
A.M. Aksonova, V.V. Belicov, S.A. Vdovin, P.L. Makhnenko, M.M. Pylypenko, A.P. Podolyak,
E.I. Ponomarchuk, O.P. Svynarenko, V.I. Skibin
National Science Center “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine
E-mail: anna.aksynova@gmail.com
The rates of pumping hydrogen and nitrogen by the non-evaporable Zr(86)-Al(14) getter located inside the
chamber of a plasma-ion proton injector are investigated. The measurements at the temperature range 473…1300 K
and pressures from 13 to 10
-3
Pa were carried out. The highest pumping rates of hydrogen ((283±15) l/s) and
nitrogen ((133±15) l/s) achieved at the temperature range 525…575 K and pressure from 13 to 10
-3
Pa has been
established. It is shown that the proposed non-evaporated getter Zr(86)-Al(14) provided the required operating
pressure in the chamber of the plasma-ion injector of the linear proton accelerator and the minimum concentration of
hydrogen, nitrogen, and other residual gases.
PACS: 81.05.-t, 07.30.-t
INTRODUCTION
The use in the linear proton accelerator [1] of the
non-evaporated Zr(86)-Al(14) getter, located in the
chamber of the plasma-ion proton injector for its
additional pumping out, can significantly improve the
injector performance. And this makes it possible to
expand the use of the accelerator both in the fields of
scientific research and applied applications. It should be
noted that these are one of the areas that determine the
progress of modern development of science and
technology [2, 3]. The proton injector is that part of the
accelerator design that largely determines the quality of
the accelerator operation and, as a consequence, the
efficiency of its use. For the normal operation of a
linear proton accelerator, it is necessary that the system
of its vacuum pumping would provide the required
pressure in the vacuum case of the accelerator, the
proton injector and the channel where the protons are
accelerated before hitting the target. In this case, the
largest gas load during the operating accelerator takes
place in the chamber of the proton injector, which
requires its additional pumping out. For this purpose,
during the research, a non-evaporated Zr(86)-Al(14)
getter was used, which made it possible to maintain in
the injector chamber both the required operating
pressure and the composition of residual gases with the
minimum necessary concentration of hydrogen and
other impurities in them: hydrocarbons, water vapor,
their fragments, noble gases ...
Analysis of literature data [1] and preliminary
studies carried out in this work showed that the
placement of the Zr(86)-Al(14) getter inside the injector
chamber for its additional pumping has advantages over
all other methods used for pumping hydrogen in a
vacuum volume with high hydrogen gas load.
Therefore, the proposed method for placing this getter
will improve the performance of the injector. Thus, by
changing the temperature of the getter, it is possible to
set the required pressure of residual gases, including
hydrogen, in the injector chamber in a more controlled
manner.
The non-evaporated Zr(86)-Al(14) getter used in this
study, also known as St (101), is capable, under certain
conditions, of absorbing irreversibly reactive gases: О2,
N2, СО, СО2, water vapor, hydrocarbons – СН4, С2Н2,
С2Н4, their fragments: СН, СН2, СН3, and reversibly –
hydrogen and its isotopes.
The properties of the getter proposed for use in this
work, its operating characteristics, and application
features are described, for example, in [4–6].
Over time, during the operation of the getter, its
sorbing surface is passivated and the rate of gas sorption
decreases to an unacceptable level. Therefore, it is
necessary to set both the time until the next activation of
the getter surface and the possible time of its use for
operation in the accelerator. And this can only be done
experimentally. Therefore, this information is of
interest, since make it possible to determine the most
acceptable operating conditions of the injector in the
accelerator, which will make it possible to improve the
performance of the accelerator and, thereby, the
efficiency of its use.
The purpose of this work is to determine the optimal
operating parameters of the injector chamber – its
working pressure, to achieve the minimum required
residual pressure of hydrogen, nitrogen and other gases,
to determine the operating time of the proposed getter
before the next next activation of the surface and the
total time of its operation.
RESEARCH TECHNIQUE
To study the rates of pumping out hydrogen and
nitrogen from the injector chamber with a getter placed
inside it, the “constant volume” method was used [7].
In Fig. 1 shows a schematic diagram of pumping out
the injector chamber (a) and a view of its internal
structure (b). Chamber 1, in which the getter 2 is
located, is pumped out by three fore-vacuum pumps of
the BNR-2 type 3 and two vapor-oil diffusion pumps of
the VM-5 type 4. With the help of five vacuum valves
ISSN 1562-6016. ВАНТ. 2022. №1(137) 47
5, the pressure required to perform a specific
experiment is created in it. Hydrogen is injected into the
injector chamber through valve 6, and the pressure in it
is measured by three gauge transducers 7.
a
b
Fig. 1. Schematic diagram of pumping the injector
chamber: 1 – injector chamber; 2 – getter;
3 – backing pumps; 4 – oil-vapor diffusion pump;
5 – vacuum valve; 6 – hydrogen inlet valve into the
injector chamber; 7 – gauge converters (a). View of the
internal structure of the injector chamber (b)
When conducting research in the pressure range:
13.33…0.13 and 0.13…10
-5
Pa, converters LT-2 and
LM-2 with a VIT-3 vacuum gauge were used, in the
range 133.3…10
-3
Pa – converter PM-10-2. The
measurement of the partial pressures of the residual
gases in the injector chamber in the range of
1.33…10
-8
Pa was carried out by a PMI-27 manometric
transducer with a VI-14 vacuum gauge.
The view of the internal structure of the injector
chamber is shown in Fig. 1,b.
The injector chamber has a design typical for
injectors of known proton accelerators. All parts of the
injector, their location and dimensions are designed and
manufactured in such a way as to maximally meet the
requirements for the operation of the accelerator.
SAMPLES FOR RESEARCH
Particles of a getter extracted from crushed ingots
obtained by fusion of iodide zirconium and aluminum
(99.998%) were used as samples for research. The
fusion was carried out by the method of arc melting
with a non-consumable tungsten electrode. The
resulting ingots were crushed mechanically and particles
of ~ 0.02…0.04 cm in size were separated from the
crushed mass. In the injector chamber, they were
located on a tape made of X18H10T stainless steel
placed on insulators.
In Fig. 2 shows a part of this tape with getter
particles located on it.
а b
Fig. 2. Part of the tape with getter particles located on
it (top view): a – decreased by 4 times;
b – increased by 10 times
The getter is distinguished by high operational
reliability, its operation is stable for a long time (more
than 500 h). It does not crumble with the release of solid
particles into the injector chamber when it is heated to
temperatures above 1200 K, which significantly reduces
the risk of electrical breakdowns in it.
The getter temperature in the injector chamber was
measured with a chromel-alumel thermocouple, which
was located on the surface of the tape under the layer of
getter particles.
RESULTS AND DISCUSSION
In this work, to obtain protons, plasma is used,
formed in the injector chamber with the help of high-
frequency fields. This method of producing protons can
initiate a high-voltage breakdown in the chamber with
the further establishment of a gas discharge with self-
sustaining electron-ion avalanches that violate its
dielectric strength. In this case, a malfunction of the
accelerator, damage to its individual units and, as a
consequence, unsuitability for further operation is
possible. In this case, a malfunction of the accelerator,
damage to its individual units and, as a consequence,
unsuitability for further operation is possible.
When choosing the working pressure in the injector
chamber, it is necessary to take into account that as the
pressure decreases, the mean free path of electrons
increases and they acquire more energy in the electric
field. However, in this case, the number of collisions
with atoms of residual gases, including with hydrogen
atoms, decreases, which leads to a decrease in the
number of protons formed [3].
One of the main requirements for the composition of
residual gases in the injector chamber is the minimum
concentration of hydrogen in it. It is impossible to
estimate with sufficient accuracy its amount that passed
ionization and then hit the accelerator target as protons.
These protons have different velocities and
therefore, when they are decelerated on a stationary
target, the temperature control of which is not provided
for in its design, results with a wide range of values are
obtained, which complicates their correct interpretation.
Ultimately, this leads to a decrease in the efficiency of
the accelerator application.
The results of measurements of the rates of pumping
out hydrogen (SH) and nitrogen (SN), obtained in this
work with the getter located inside the injector chamber,
48 ISSN 1562-6016. ВАНТ. 2022. №1(137)
are presented in the Table and in Figs. 3 and 4; in the
Table at a pressure in the chamber of 10
-3
Pa, and in
Figs. 3 and 4 – at a pressure in it of 10
-2
and ~ 10
-3
Pa,
respectively.
All measurements were carried out for the case
when the injector chamber is included in the general
vacuum pumping system of the accelerator, i.e. valve 6
shown in Fig. 1,a, is open.
Results of measurements of the pumping rate of
hydrogen (SH) and nitrogen (SN) at a pressure in the
injector chamber of 10
-3
Pa
No Т, К
SH,
l/s
SN,
l/s
No
Т,
К
SH,
l/s
SN,
l/s
1 473 155.3 73.0 9 593 193.6 91.0
2 483 236.0 111.0 10 603 193.6 91.0
3 503 236.0 111.0 11 613 193.6 91.0
4 513 236.0 111.0 12 623 155.3 73.0
5 523 283.0 133.0 13 633 55.3 26.0
6 553 283.0 133.0 14 643 55.3 26.0
7 573 283.0 133.0 15 653 55.3 26.0
8 583 236.0 111.0 16 673 0 0
The rates of pumping out hydrogen and nitrogen in
the injector chamber were obtained for the temperature
range 473…673 K in the case when the sorbing surface
of the getter is not strongly passivated and its ability to
absorb residual gases remains at a rate close to the
maximum for this temperature range.
From the results presented in the table, it is
necessary to note a decrease in SH and SN with an
increase in temperature from ~ 550 to 675 K, where
they are no longer registered by the method used in this
work.
Fig. 3 shows the temperature dependences of SH and
SN at a pressure in the injector chamber of 10
-2
Pa for
the case when a getter is placed in it.
Fig. 3 shows that the rates of hydrogen absorption
are relatively low in the entire range of the studied
temperatures. So, for hydrogen it does not exceed
~ 60 l/s, nitrogen ~ 30 l/s. In this case, the change in SH
and SN with a temperature in the range of 475…675 K is
~ 10 l/s for SH and ~ 3 l/s for SN. Such relatively small
ranges of changes in the temperature dependences of SH
and SN significantly limit the possibility of finding the
optimal operating mode of the injector at a pressure in
its chamber of 10
-2
Pa. Therefore, this pressure is not
acceptable for injector operation.
Fig. 3. Temperature dependences of SH ( )and SN ( ) at
a pressure in the injector chamber of 10
-2
Pa
Fig. 4 shows that the lines describing the
temperature dependences of SH and SN have maxima
located in the temperature range 525…575 K, and they
converge to the point where the temperature is 675 K.
As the pressure in the injector chamber decreases to
10
-3
Pa, the shape of the curves describing the
temperature dependences of SH and SN changes
significantly (see Fig. 4).
Fig. 4. Temperature dependences of SH ( ) and SN ( ) at
a pressure in the injector chamber of 10
-3
Pa
Comparison of the temperature dependences of SH
and SN at pressures of 10
-2
and 10
-3
Pa shows that for the
entire temperature range at which the measurements
were carried out, the values obtained at a pressure in the
injector chamber of 10
-3
Pa are always higher than at
10
-2
Pa. In the temperature range 525…575 K, these
rates have the highest values and decrease with
increasing temperature, even at ~ 625 K are quite
sufficient to control and select the optimal injector
operation mode with acceptable accuracy.
Shown in Fig. 5, the curve showing the temperature
dependence of the specific rate of hydrogen pumping by
the non-evaporated getter Zr(86)-Al(14) at a pressure in
the injector chamber of 10
-3
Pa is quite informative.
It can be seen from its analysis that the selected
getter provides the required pressure in the injector
chamber in the temperature range: 475…675 K. Starting
from a temperature of 550 K, the dependence of the
specific rate of hydrogen pumping decreases, and at a
temperature of ~ 605 K it has an inflection point and
then approaches zero, to the point corresponding to
675 K, where the absorption of hydrogen is no longer
recorded by the method used in this work. The data
presented in Fig. 5 also confirm that the method of
using the getter – placing it inside the injector chamber
in the form of particles of a certain size and using the
activation of its surface to bring it into the state to sorb
gases – is quite justified. Thus, the facts presented
above allow us to assert that one of the main
requirements for the getter proposed for use is
fulfilled – the provision of the required operating
pressure in the injector chamber during accelerator
operation. These facts also make it possible to better
understand and use the technological capabilities of the
proposed getter.
In Fig. 6 shows a histogram of partial pressures in
the injector chamber at a pressure of 10
-3
Pa for the case
when its additional pumping inside the injector is
carried out by a non-evaporated getter.
ISSN 1562-6016. ВАНТ. 2022. №1(137) 49
Fig. 5. Temperature dependence of the specific rate of
hydrogen pumping by a non-evaporated Zr(86)-Al(14)
getter from the injector chamber at a pressure of 10
-3
Pa
(taking into account the edge temperature effect l/d,
where l is the length of the tape covered with getter
particles, and d is its width)
Fig. 6. Histogram of the composition of residual gases
in the injector chamber at a pressure of 10
-3
Pa
The measurement results presented in the histogram
were obtained before the outgassing of the walls of the
injector chamber and the proton acceleration channel.
Comparison of the measurement results shown in
Fig. 6, with similar ones, but only for the case when the
additional pumping of the injector chamber is carried
out by electric discharge pumps of the NORD-250 type,
showed that the use of a non-evaporated getter has a
significant advantage – a lower concentration of
hydrogen and other impurities in the chamber,
determined in the composition of residual gases at a
pressure in her 10
-3
Pa.
All measurements were carried out before degassing
the walls of the chamber and the proton acceleration
channel. The results shown in Fig. 6 – partial pressures
of residual gases (or, more correctly, the mass numbers
corresponding to them) are characteristic of vacuum
volumes, the inner surfaces of which have not been
subjected to any special treatment [8]. The highest
concentrations are found for hydrogen and argon. Other
mass numbers presented on the histogram refer to
hydrocarbons (CH4, C2H4), water vapor, and their
fragments.
When analyzing the results presented on the
histogram, it is necessary to take into account that the
techniques used to study the gaseous medium strongly
depend on many factors: the instruments used, their
distance to the vacuum volumes where measurements
are taken, the diameter of the supply pipes, the vacuum
fittings used – vacuum taps, valves, connecting sleeves,
angles, vacuum seals, etc. Therefore, these techniques
may somewhat fail to reflect the real picture, which
takes place in a vacuum volume, but not even detect
gases with a high sorption bond energy, for example,
water vapor or oxygen. Instead of these components of
the gaseous environment, the content of hydrogen and
inert gases will be overestimated [8]. Therefore, when
explaining and using the results presented in the
histogram, they should be considered only as qualitative
estimates.
However, these estimates are sufficient to draw a
conclusion about the compliance of the composition of
the residual gases in the injector chamber with the
requirements imposed on them – an acceptable
minimum content of hydrogen and other impurities
characteristic of these operating conditions of the
accelerator.
It is practically impossible to quantify the
composition of residual gases presented in the
histogram. For a pressure of 10
-3
Pa, at which the
measurements were carried out, this composition can
differ significantly depending on the history of the inner
surface of the injector and the state of it at the time of
measurements. And this state is determined by the
superposition of many, poorly controlled,
simultaneously occurring processes on its surface [9].
Comparison of all the results obtained in this study
showed that the non-evaporated Zr(86)-Al(14) getter,
proposed for additional pumping out of the injector
chamber, can provide both the required operating
pressure and an acceptable composition of residual
gases in it, i.e. meet the requirements for a getter when
used in a linear proton accelerator.
The operation of this accelerator with improved
injector performance for more than 500 h is a sufficient
justification for the feasibility of using the proposed
getter.
An important factor when using a non-evaporated
getter by the method proposed in this work is also a
decrease in power consumption during operation of the
accelerator. So, its savings when replacing previously
used electric discharge pumps is 14.8 kW·h for one
working day lasting eight hours for one electric
discharge pump of the NORD-250 type.
CONCLUSIONS
1. The use of a non-evaporated Zr(86)-Al(14) getter
for additional pumping of hydrogen from the injector
chamber of a linear proton accelerator has significant
advantages over all known previously applied methods.
2. The pumping rates of the hydrogen ((283±15) l/s)
and nitrogen ((133±15) l/s) for additional pumping out
of the chamber of the plasma-ion proton injector
obtained in this work provide the required operating
pressure (10
-3
Pa ) and the composition of the residual
gases with an acceptable content of hydrogen, nitrogen
and other impurities.
3. It was found that the performance of the injector
using a non-evaporated getter Zr(86)-Al(14) is
maintained for more than 500 h, while saving energy
consumption.
4. The analysis of all the results obtained in this
study made it possible to better understand the processes
occurring in the injector chamber of the linear
accelerator of protons and thereby more thoughtfully
(s
∙c
m
2
)
50 ISSN 1562-6016. ВАНТ. 2022. №1(137)
and purposefully plan and carry out the necessary
experiments on it.
REFERENCES
1. V.V. Koloskov et al. Linear proton accelerator I-
2. Vacuum system // Instruments and experimental
techniques. 1967, N 5, p. 43.
2. N.I. Aizatsky, Yu.M. Arkatov, V.A. Bomko, et al.
Academician Anton Karlovich Walter, Part II, NSC
KIPT. Kharkov: Fort Publishing House, 2005, 235 p.
3. G.L. Saksaganskiy. VIII International Vacuum
Congress // Express information of TsINTI and TEP on
chemical and petroleum engineering. Series XM-6.
1986, N 4, p. 16.
4. V.M. Azhazha, P.N. Vyugov, I.E. Kopanets, et al.
Accumulation and retention of hydrogen and deuterium
in zirconium alloys and low-alloy steels with additions
of getter alloys based on zirconium // Problems of
Atomic Science and Technology. Series ”Vacuum, Pure
materials, Superconductors”. 2006, N 1, p. 41-48.
5. Sorb AC Curtridge pumps: SAES-Getters
advertising catalog. SAES Group www.saesgroup.com
neg_technology@saes-group.com
6. V.S. Kogan, V.M. Shulaev. Adsorption-diffusion
vacuum pumps with non-sprayable getter: Review. M.:
“CRI of Atominform”, 1990, 67 p.
7. D.Zh. Yarwood. High vacuum technique // M.:
“Gosenergoizdat”, 1960, 313 p.
8. N.V. Cherepnin. Sorption phenomena in vacuum
technology. M.: “Soviet. radio”, 1973, 383 p.
9. P. Dore. Surface treatment and material
degassing. Sorption processes in vacuum // M.:
“Atomizdat”, 1966, chapter 15, 313 p.
Article received 17.06.2021
ПРИМЕНЕНИЕ В ЛИНЕЙНОМ УСКОРИТЕЛЕ ПРОТОНОВ НЕИСПАРЯЕМОГО
ГЕТТЕРА Zr(86)-Al(14), РАЗМЕЩЕННОГО ВНУТРИ КАМЕРЫ ПЛАЗМЕННО-ИОННОГО
ИНЖЕКТОРА ПРОТОНОВ ДЛЯ ЕЕ ДОПОЛНИТЕЛЬНОЙ ОТКАЧКИ
А.Н. Аксенова, В.В. Беликов, С.А. Вдовин, П.Л. Махненко, Н.Н. Пилипенко, А.П. Подоляк,
Е.И. Пономарчук, А.П. Свинаренко, В.И. Скибин
Проведены измерения скоростей откачки водорода и азота в камере плазменно-ионного инжектора
протонов с размещенным внутри нее неиспаряемым геттером Zr(86)-Al(14). Измерения проведены в
интервале температур 473…1300 К и давлений 13…~ 10
-3
Па. Установлены наибольшие скорости откачки
водорода ((283±15) л/с) и азота ((133±15) л/с), достигаемые в интервале температур 525…575 К и давлений
13…~10
-3
Па. Показано, что предложенный неиспаряемый геттер Zr(86)-Al(14) обеспечивает необходимое
рабочее давление в камере плазменно-ионного инжектора линейного ускорителя протонов и минимальную
концентрацию водорода, азота и других остаточных газов.
ВИКОРИСТАННЯ В ЛІНІЙНОМУ ПРИСКОРЮВАЧІ ПРОТОНІВ ГЕТЕРА Zr(86)-Al(14),
ЩО НЕ ВИПАРОВУЄТЬСЯ, РОЗМІЩЕННОГО ВСЕРЕДИНІ КАМЕРИ ПЛАЗМОВО-
ІОННОГО ІНЖЕКТОРА ПРОТОНІВ ДЛЯ ЇЇ ДОДАТКОВОГО ВІДКАЧУВАННЯ
Г.М. Аксьонова, В.В. Бєліков, С.А. Вдовін, П.Л. Махненко, М.М. Пилипенко, А.П. Подоляк,
Є.І. Пономарчук, О.П. Свинаренко, В.І. Скібін
Проведені виміри швидкостей відкачування водню і азоту в камері плазмово-іонного інжектора протонів
з розташованим всередині неї для її додаткового відкачування гетером Zr(86)-Al(14), що не випаровується.
Виміри проведені в інтервалі температур 473…1300 К і тисків 13…~ 10
-3
Па. Установлені найбільші
швидкості відкачування водню ((283±15) л/с) і азоту ((133±15) л/с), що досягаються в інтервалі температур
525…595 К і тисків 13…~ 10
-3
Па. Показано, що запропонований гетер, що не випаровується, Zr(86)-Al(14)
забезпечує необхідний робочий тиск у камері плазмово-іонного інжектора лінійного прискорювача протонів
та мінімальну концентрацію водню, азоту та інших залишкових газів.
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