Beam position measurement for electron cooler EC-300 and EC-35
The beam position measurement system of EC-35 and EC-300 is presented in this paper. The electrostatic pickup is used for beam position measuring. The ion and electron currents have alternative part with the magnitude of about 1 mA. The important feature of the beam position measurement system (BP...
Saved in:
| Date: | 2006 |
|---|---|
| Main Author: | |
| Format: | Article |
| Language: | English |
| Published: |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2006
|
| Series: | Вопросы атомной науки и техники |
| Subjects: | |
| Online Access: | http://dspace.nbuv.gov.ua/handle/123456789/78863 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Journal Title: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Cite this: | Beam position measurement for electron cooler EC-300 and EC-35 / E. Bekhtenev // Вопросы атомной науки и техники. — 2006. — № 2. — С. 108-109. — Бібліогр.: 2 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-78863 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-788632015-03-23T03:02:09Z Beam position measurement for electron cooler EC-300 and EC-35 Bekhtenev, E. Линейные ускорители заряженных частиц The beam position measurement system of EC-35 and EC-300 is presented in this paper. The electrostatic pickup is used for beam position measuring. The ion and electron currents have alternative part with the magnitude of about 1 mA. The important feature of the beam position measurement system (BPM system) is simultaneous measurements of the positions of both the ion and the electron beams. The resolution of the beam position measurement is about 1 mm, diameter vacuum chamber 300 mm. Описана система измерения положения пучков электронов и ионов в установках электронного охлаждения ЕХ-300 и ЕХ-35. Для определения положения пучков применяются электростатические пикапы. Важной особенностью системы измерения положения пучков является её способность одновременно измерять положения как ионов, так и электронов. Разрешение измерения положения пучков около 1 мм при диаметре вакуумной камеры 300 мм. Описано систему виміру положення пучків електронів і іонів в установках електронного охолодження ЕХ-300 і ЕХ-35. Для визначення положення пучків застосовуються електростатичні пікапи. Важливою особливістю системи виміру положення пучків є її здатність одночасно вимірювати положення як іонів, так і електронів. Розділення виміру положення пучків близько 1 мм при діаметрі вакуумної камери 300 мм. 2006 Article Beam position measurement for electron cooler EC-300 and EC-35 / E. Bekhtenev // Вопросы атомной науки и техники. — 2006. — № 2. — С. 108-109. — Бібліогр.: 2 назв. — англ. 1562-6016 PACS: 29.20.-c http://dspace.nbuv.gov.ua/handle/123456789/78863 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 Bekhtenev, E. Beam position measurement for electron cooler EC-300 and EC-35 Вопросы атомной науки и техники |
| description |
The beam position measurement system of EC-35 and EC-300 is presented in this paper. The electrostatic pickup
is used for beam position measuring. The ion and electron currents have alternative part with the magnitude of
about 1 mA. The important feature of the beam position measurement system (BPM system) is simultaneous measurements
of the positions of both the ion and the electron beams. The resolution of the beam position measurement
is about 1 mm, diameter vacuum chamber 300 mm. |
| format |
Article |
| author |
Bekhtenev, E. |
| author_facet |
Bekhtenev, E. |
| author_sort |
Bekhtenev, E. |
| title |
Beam position measurement for electron cooler EC-300 and EC-35 |
| title_short |
Beam position measurement for electron cooler EC-300 and EC-35 |
| title_full |
Beam position measurement for electron cooler EC-300 and EC-35 |
| title_fullStr |
Beam position measurement for electron cooler EC-300 and EC-35 |
| title_full_unstemmed |
Beam position measurement for electron cooler EC-300 and EC-35 |
| title_sort |
beam position measurement for electron cooler ec-300 and ec-35 |
| 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/123456789/78863 |
| citation_txt |
Beam position measurement for electron cooler EC-300 and EC-35 / E. Bekhtenev // Вопросы атомной науки и техники. — 2006. — № 2. — С. 108-109. — Бібліогр.: 2 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT bekhteneve beampositionmeasurementforelectroncoolerec300andec35 |
| first_indexed |
2025-07-06T02:58:01Z |
| last_indexed |
2025-07-06T02:58:01Z |
| _version_ |
1836864695089233920 |
| fulltext |
BEAM POSITION MEASUREMENT
FOR ELECTRON COOLER EC-300 AND EC-35
E. Bekhtenev
Budker INP, Novosibirsk, Russia
E.A.Bekhtenev@inp.nsk.su
The beam position measurement system of EC-35 and EC-300 is presented in this paper. The electrostatic pick-
up is used for beam position measuring. The ion and electron currents have alternative part with the magnitude of
about 1 mA. The important feature of the beam position measurement system (BPM system) is simultaneous mea-
surements of the positions of both the ion and the electron beams. The resolution of the beam position measurement
is about 1 mm, diameter vacuum chamber 300 mm.
PACS: 29.20.-c
1. INTRODUCTION
The Budker Institute of Nuclear Physics (BINP) had
been manufacturing two facilities of electron cooling
(electron cooler) of ion beam EC-35 and EC-300 during
1999-2003. The facilities had been prepared for the In-
stitute of Modern Physics (IMP China, Lanzhou) for in-
stallation on a new ion accelerator complex HIRFL-
CSR [1]. HIRFL-CSR is a multi-purpose system. It con-
sists of an injector HIRFL, a main ring (CSRm) and an
experimental ring (CSRe). Each of the rings is equipped
with its own electron cooling devices. E-cooling will be
used to increase the beam intensity and decrease the
beam emittance. The principle of operation of electron
cooling method is based on combining the electron and
ion beams moving with the same velocity within the
cooling section. So, the drag force between the electrons
and ions leads to the fine equalizing of the ion and elec-
tron velocities. This method is used for the decrease of
ion transverse emittances and momentum spread [2].
The cooler consists of a cooling section solenoid,
two bending magnets, an electron gun, and a collector.
Beam Position Monitors (BPM) are located at both sides
of the solenoid. A sketch of the facility and BPM posi-
tion is shown in Fig.1.
e-
Gun Collector
Ions
35-300 KV
BPM1 BPM2 solenoid
Fig.1. Electron cooler and the BPM
Some parameters of the accelerator complex and the
cooler are shown in Table.
Parameters of the complex and the cooler
Parameter Value
Ion energy 25…500 MeV/u
Ion current 0.1…1 mA
Ion revolution frequency 100…300 kHz
Electron DC current 3 A
Electron AC component 1 mA
Vacuum chamber diameter 300 mm
Cooler length 6 m
For the electron cooling process an ion and an elec-
tron beams must have the same trajectories within the
cooling section. The important feature of the BPM sys-
tem is simultaneous measurements of the positions of
both the ion and the electron beams. For this purpose
the ion and electron beams are modulated with different
frequencies. Ion beam is modulated with a frequency of
RF system 100…300 kHz. Electron current is modulat-
ed by means of feeding on the gun grid of voltage with a
frequency 3 MHz. The diameter of the electron beam is
about 10…20 mm. So the resolution of beam position
measurement for adjustment of the cooler has to be of
order of 1 mm.
2. POSITION MEASUREMENT
The BPM system consists of two beam position
monitors (BPM), pickup stations, ADC, a synchronous
detector and a reference generator (see Fig.2).
The electrostatic beam position monitors with linear
transfer ratio are used at the cooler. Each BPM consists
of two parts. Each part has two electrodes and measures
either the vertical or the horizontal coordinate.
Pickup station (PS) is located near the BPM. It is in-
tended for the preliminary processing of the BPM sig-
nals. PS produces sum and difference signals coming
from the pick-up electrodes. The sum of all signals UΣ is
proportional to the beam current. The difference signals
UZ and UX are proportional to the beam deviation in ver-
tical (Z) and horizontal (X) direction correspondingly.
Bandwidth of the PS is 80 kHz…5 MHz. The gain fac-
tor is regulated in the range of 40 db.
Other electronics is located in the CAMAC crate.
The Reference generator produces reference signals for
the synchronous detector and ADC, as well it produces
signal for the modulation the electron beam. The refer-
ence signal generator receives the RF frequency from
the accelerator complex (RF i+) and produces two or-
thogonal signals. Results of the signal analog-to-digit
conversion come to the computer, where the calculation
of beam position is produced. The multiplexer in the
synchronous detector input chooses one of the signals
(UΣ, UZ, UX) processed. As the reference for the syn-
chronous detector the signal shifted either by 0° or by
90° comes from the Reference generator. Total time of
the position measurement for both ion and electron
beams for two BPM is about 500 us.
___________________________________________________________
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2006. № 2.
Series: Nuclear Physics Investigations (46), p.108-109.108
BPF 0.08-5 MHz
gun
e-
Pickup station 1
Pickup station 2
UX, UZ, UΣ
UX, UZ, UΣ
Syn.
detector
SD
ADC CAMAC
Reference generator
3MHz
RF i+
ions
X
Z
Σ
0°-90°
driv.
0°-90°
Fig. 2. System of beam position measurement
The beam coordinates are calculated with a formula:
ΣΣ
Σ
⋅
⋅⋅=
UU
UUAX X
X ,
where: X – coordinate; AX – geometric factor; XU –
complex voltage proportional to the deviation of the
beam (it is formed with two orthogonal component);
ΣU – complex voltage proportional to the beam current.
3. ELECTRON BEAM MODULATION
The focusing grid at the gun is used for modulation
of electron beam [1]. The voltage with frequency
3 MHz from the 3W amplifier is supplied to the grid.
The light guide is used for the electrostatic isolation,
since the gun and amplifier are under the potential of
35 kV for the cooler EC-35 and 300 kV for EC-300, re-
spectively.
4. CONCLUSION
The testing of the coolers EC-35 and EC-300 has
been performed at BINP and IMP. Since these tests
were performed without the installation in the ring no
tests with ions were carried out. During these tests all
cooler systems including the beam position measure-
ment system were checked. The parameters of the elec-
tron beam were measured. The parameters of beam po-
sition measurement system were measured also. Resolu-
tion of beam position measurement was 0.4 mm with
the current modulation of 1 mA. The DC current of the
electron beam was changed within the range of 0…3 A.
When DC current is changed the alternating component
of the beam current is changed proportionally to DC
current if the modulation voltage on the grid is constant.
The possibility of the regulating of the modulation volt-
age on the grid allows keeping of the desired value of
the AC component of electron beam. Resolution of
beam position measurement in the DC current range
0.5…3 A not worse than 1 mm, resolution becomes
worse at a smaller beam current.
The author expresses thanks to V. Parkhomchuk,
V. Reva and V. Berezkin for help in this work and use-
ful advices.
REFERENCES
1. E. Behtenev, V. Bocharov, V.Bubley et al. Com-
mission of electron cooler EC-300. Proc. of EPAC-
04. Lucerne. 2004.
2. V.V. Parkhomchuk. New insights in the theory of
electron cooling // Nucl. Instr. Methods. 2000,
A441.
СИСТЕМА ИЗМЕРЕНИЯ ПОЛОЖЕНИЯ ПУЧКА ДЛЯ УСТАНОВКИ ЭЛЕКТРОННОГО
ОХЛАЖДЕНИЯ ЭПОХА-300 И ЭПОХА-35
Е.А. Бехтенев
Описана система измерения положения пучков электронов и ионов в установках электронного охлажде-
ния ЕХ-300 и ЕХ-35. Для определения положения пучков применяются электростатические пикапы. Важной
особенностью системы измерения положения пучков является её способность одновременно измерять поло-
жения как ионов, так и электронов. Разрешение измерения положения пучков около 1 мм при диаметре ва-
куумной камеры 300 мм.
СИСТЕМА ВИМІРУ ПОЛОЖЕННЯ ПУЧКА ДЛЯ УСТАНОВКИ ЕЛЕКТРОННОГО
ОХОЛОДЖЕННЯ ЕПОХА-300 І ЕПОХА-35
Е.А. Бехтенєв
Описано систему виміру положення пучків електронів і іонів в установках електронного охолодження
ЕХ-300 і ЕХ-35. Для визначення положення пучків застосовуються електростатичні пікапи. Важливою
особливістю системи виміру положення пучків є її здатність одночасно вимірювати положення як іонів, так
і електронів. Розділення виміру положення пучків близько 1 мм при діаметрі вакуумної камери 300 мм.
___________________________________________________________
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2006. № 2.
Series: Nuclear Physics Investigations (46), p.108-109.108
Система измерения положения пучка для установки электронного охлаждения ЭПОХА-300 И ЭПОХА-35
|