RuPAC2021 - List of Keywords (focusing)

Paper	Title	Other Keywords	Page
MOY05	Linear Induction Accelerator LIA-2 Upgrade	cathode, simulation, induction, space-charge	17
	D.A. Starostenko BINP SB RAS, Novosibirsk, Russia
	X-ray complexes based on a linear induction accelerator are designed to study of high density objects. It requires of high-current electron beam to obtain a small spot and bright x-ray source using a conversion target. The electrons source in such installations is injectors capable generate pulses with a duration from tens of nanoseconds to several microseconds and a current of several kiloamperes. The transportation and focusing such beams into diameter about 1 mm is difficult due to of the space charge effect. In similar induction accelerators (DARHT, AIRIX, FXR, etc.), auto-emission cathodes are used to obtain high-current electron beams. The use of a thermionic cathode, in compared to auto-emission cathode, provides stable generation of several pulses with a time interval of several microseconds, but makes high requirements on the injector vacuum system: not less than 10^-7 Torr.
	Slides MOY05 [3.946 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-MOY05
About •	Received ※ 24 September 2021 — Revised ※ 05 October 2021 — Accepted ※ 13 October 2021 — Issued ※ 23 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPSA53	Focusing Properties of the Magnetic Structure of Isochronous Cyclotrons With Large Spiraling Angle of Pole Tips	cyclotron, ECR, factory, H-minus	219
	D.A. Amerkanov, S.A. Artamonov, E.M. Ivanov, G.A. Riabov, V.A. Tonkikh PNPI, Gatchina, Leningrad District, Russia
	Magnetic structures with a high spiraling angle of pole tips are used in superconducting cyclotrons, H⁻ ion cyclotrons, etc. and they have been investigated in a number of works. In connection with the design of an 80 MeV isochronous H⁻ cyclotron, such studies were continued and extended. The paper proposes a relatively simple approach for analyzing the projected spiral structure. The main conclusions can be formulated as follows. The introduction of spiraling makes it possible to significantly increase the vertical focusing, but in the central region at radii smaller than the gap in the hills, the structure with high spiraling angle becomes ineffective and can lead to a decrease in focusing. Each radius can be associated with a limiting spirality angle, above which spiraling leads to a resultant decrease in vertical focusing. The spiraling of the magnetic field does not coincide with the geometric spiraling of the pole tips, which should be taken into account when designing the cyclotron structure. The developed technique can be useful for a quick analysis of various options and will reduce the amount of time-consuming calculations by using 3D programs.
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-MOPSA53
About •	Received ※ 07 September 2021 — Accepted ※ 10 September 2021 — Issued ※ 15 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPSB08	Magneto-Optical Structure of the NICA Collider With High Critical Energy	quadrupole, sextupole, dynamic-aperture, collider	245
	S.D. Kolokolchikov, V. Senichev RAS/INR, Moscow, Russia E. Syresin JINR, Dubna, Moscow Region, Russia
	In the proton option of the NICA collider, there is a problem of crossing transition energy. To do this, we have investigated ways to increase the critical energy for the proton option of the NICA collider. The method of superperiodic modulation of quadrupole gradients is applied. Two variants of dispersion suppression on the arch for matching with straight sections are considered. The selection of sextupoles is carried out to suppress the natural chromaticity and compensate for the sextupole component. The Twiss parameters for the proposed structures are given, as well as the dynamic apertures and working points are investigated.
	Poster TUPSB08 [3.646 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-TUPSB08
About •	Received ※ 17 September 2021 — Revised ※ 27 September 2021 — Accepted ※ 02 October 2021 — Issued ※ 21 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPSB39	Study of Space Charge Compensation Process of a 400 KeV Pulsed Hydrogen Ion Beam	electron, space-charge, plasma, ion-source	313
	A. Belov, O.T. Frolov, S.A. Gavrilov, L.P. Nechaeva, A.V. Turbabin, V. Zubets RAS/INR, Moscow, Russia
	Funding: Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, Russia A three grid energy analyzer of slow secondary ions with a twin analyzing grid is described. The analyzer has cylindrical geometry and Pi angle for recording of the slow ions. The analyzer has been used for measurements of degree of space-charge compensation (SCC) of a pulsed hydrogen ion beam with energy of 400 keV and peak beam current of 60 mA. Results of the measurements are presented and compared with theoretical estimations based on model in which the SCC degree is limited by heating of electrons in collisions with fast ions of the beam.
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-TUPSB39
About •	Received ※ 20 September 2021 — Revised ※ 05 October 2021 — Accepted ※ 09 October 2021 — Issued ※ 16 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPSC17	Vibrating Wire System for Fiducialization NICA Booster Superconducting Quadrupole Magnets	quadrupole, booster, collider, synchrotron	379
	T. Parfylo, M.A. Kashunin, V.A. Mykhailenko JINR/VBLHEP, Dubna, Moscow region, Russia V.V. Borisov, H.G. Khodzhibagiyan, B.Yu. Kondratiev, S.A. Kostromin, M.M. Shandov JINR, Dubna, Moscow Region, Russia
	The NICA (Nuclotron-based Ion Collider fAcility) is anew accelerator complex under construction at the the Laboratory of High Energy Physics (LHEP) JINR. The facility includes two injector chains, two existing superconducting synchrotrons Nuclotron and a new Booster, under construction superconducting Collider, consisting of two rings. The lattice of the Booster includes 48 superconducting quadrupole magnets that combined in doublets. Each doublet must be fiducialized to the calculated trajectory of the beam. Alignment of the magnetic axis is necessary for properly install the magnets at the beam trajectory. The vibrating wire technique was applied to obtain the position of the magnetic axis. A new measurement system has been worked out and produced at the LHEP. The magnetic axis positions of the quadrupole doublets are determined at the ambient temperature. Thepaper describes design of the measurement system, measuring procedure and results of the magnetic axis position measurements.
	Poster WEPSC17 [0.693 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-WEPSC17
About •	Received ※ 28 September 2021 — Revised ※ 29 September 2021 — Accepted ※ 09 October 2021 — Issued ※ 22 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPSC30	Measurement of the Phase Portrait of a 2 MeV Proton Beam Along Beam Transfer Line	proton, neutron, emittance, target	399
	T.A. Bykov Budker INP & NSU, Novosibirsk, Russia Ia.A. Kolesnikov, S.Yu. Taskaev NSU, Novosibirsk, Russia Ia.A. Kolesnikov, I.M. Shchudlo, S.Yu. Taskaev BINP SB RAS, Novosibirsk, Russia S. Savinov BINP, Novosibirsk, Russia
	Funding: The research was supported by Russian Science Foundation, grant No. 19-72-30005. For the development of boron neutron capture therapy - an accelerator source of epithermal neutrons has been proposed and created at the Budker Institute of Nuclear Physics (Novosibirsk, Russia). For future therapy it is necessary to ensure the transportation of a proton beam in a high-energy beam line at a distance of 10 meters. For this purpose, using a movable diaphragm with a diameter of 1 mm, mounted on a three-dimensional vacuum manipulator, and a wire scanner, the phase portrait of the proton beam was measured. The software for remote control of the movable diaphragm and data processing of the wire scanner was developed. An algorithm for processing a series of measurements was developed to reconstruct the image of the phase portrait of the beam and calculate the emittance. This work describes in detail the features of the measuring devices, control algorithms and data processing. An experiment was carried out to measure the phase portrait and emittance of a proton beam with an energy of 2 MeV and a current of up to 3 mA. A beam of neutral particles was also measured. The effect of a bending magnet on the focusing and emittance of the beam is studied. The invariant normalized emittances calculated from the measured phase portraits make it possible to assert that the beam can be transported over distances of about 10 meters without changes in the current geometry of the high-energy beam line.
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-WEPSC30
About •	Received ※ 10 September 2021 — Revised ※ 22 September 2021 — Accepted ※ 23 September 2021 — Issued ※ 11 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRA03	Simulation and Design of the Permanent Magnet Multipole for DC140	simulation, dipole, factory, permanent-magnet	99
	V.P. Kukhtin, A.A. Firsov, M. Kaparkova, E.A. Lamzin, M.S. Larionov, A. Makarov, A. Nezhentzev, I.Yu. Rodin, N. Shatil NIIEFA, St. Petersburg, Russia N.S. Edamenko, D.A. Ovsyannikov St. Petersburg State University, St. Petersburg, Russia G.G. Gulbekyan, I.A. Ivanenko, I.V. Kalagin, N.Yu. Kazarinov, N.F. Osipov JINR, Dubna, Moscow Region, Russia S.E. Sytchevsky Saint Petersburg State University, Saint Petersburg, Russia
	Permanent magnet (PM) multipoles in some cases are good candidates in accelerator applications for beam transportation and focusing. The PM quadrupole will be utilized in the DC140 cyclotron which is under construction in JINR. A passive magnetic channel and a PM quad will be used for the compensation of horizontal defocusing in the high and low field regions, respectively. The quad is designed as a set of identical PMs rigidly fixed in a non-magnetic housing and capable to generate a a 8.1 T/m gradient field in the 64x25 mm aperture and 29.926 cm effective length. The error of linear approximation should be 1% or less. A special study was accomplished to define the PM specification reasoning from the demand for desired field strength, simple geometry, minimized nomenclature, and commercial availability. The quad design was selected with the use a 2D analytical model and then optimized in iterative 3D FE simulations with realistic PM shape and magnetic characteristics in mind. The resultant concept is the quad formed with 6 coaxial sections each 5cm in width. Every section has 26 identical PM bricks with the dimensions 11mmx11mmx50mm and different orientations. The PM bricks have remanent induction of 1.185 T and magnetic susceptibility of 0.1. Temperature characteristics and expected lifetime were also analysed. From the results obtained, candidate PM materials were proposed and mechanical and magnetic precision were recommended.
	Slides FRA03 [1.465 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRA03
About •	Received ※ 09 September 2021 — Accepted ※ 29 September 2021 — Issued ※ 12 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRB03	Upgrated the Extraction Device of Focused Electron Beam Into the Atmosphere	electron, extraction, cathode, permanent-magnet	114
	E.V. Domarov, I. Chakin, V.G. Cherepkov, S. Fadeev, M. Golkovsky, Yu.I. Golubenko, A.I. Korchagin, N.K. Kuksanov, A. Lavrukhin, P.I. Nemytov, R.A. Salimov, A.V. Semenov BINP SB RAS, Novosibirsk, Russia
	For over 30 years, an extraction device has been successfully working in BINP at the ELV-6 accelerator to extract a focused beam of electrons into the atmosphere. The accelerating tube with permanent magnetic lenses was used in this installation. The design of these accelerator tubes with magnetic lenses is rather complicated. Recently, simpler design and high reliability accelerating tubes with big aperture is operating in ELV accelerators. For this reason, the problem number one at present is to develop the extraction device, capable of reliably working with serial accelerator tubes, of the ELV accelerator with power up to100 kW. The lens L1 is located directly at the lower end of the accelerating tube. Passing the lens L1, the beam is focused near the diaphragm D6 and increases to a diameter of 10 mm in the diaphragm D5. For passing the beam along the axis of the diaphragms, there are corrections coils C1 C2 C3. The diameter of diaphragm hole D1 is the most critical, because it determines the flow of gas that should be pumped out in the following steps of the vacuum system. Measurements of the parameters of a high-power electron beam were carried out up to a power of 100 kW. As a result of the made experiments the minimum diameter of the beam at the exit from the extractions device has been 2 mm at the energy of 1,4 MeV and the beam current of 60 mA.
	Slides FRB03 [2.785 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRB03
About •	Received ※ 02 September 2021 — Revised ※ 15 September 2021 — Accepted ※ 23 September 2021 — Issued ※ 19 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRB04	A Linear Accelerator for Proton Therapy	linac, proton, acceleration, operation	117
	V.V. Paramonov, A.P. Durkin, A. Kolomiets RAS/INR, Moscow, Russia
	For applications in proton therapy, linear accelerators can provide beam performances not achievable with cyclic facilities. The results of the development of a proposal for a linac with the maximal proton energy of 230 MeV are presented. Operating in a pulsed mode, with a repetition rate not less than 50 Hz, the linac is designed to accelerate up to 10¹³ protons per irradiation cycle lasting from 10 to 200 seconds. Possibilities of fast, from pulse to pulse, adjustment of the output energy in the range from 60 MeV to 230 MeV, formation and acceleration to the output energy of a "pencil-like" beam with a diameter of ~ 2 mm are shown. Optimized solutions, proposed for both the accelerating-focusing channel and the technical systems of the linac make it possible to create a facility with high both target and technical and economic features. Special attention, due to the selection of proven in long-term operation parameters of the systems, is paid to ensuring the reliability of the linac operation. The feasibility of linac is substantiated on the basis of mastered or modified with a guarantee industrial equipment.
	Slides FRB04 [5.370 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRB04
About •	Received ※ 16 September 2021 — Revised ※ 30 September 2021 — Accepted ※ 09 October 2021 — Issued ※ 13 October 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOY05

Linear Induction Accelerator LIA-2 Upgrade

cathode, simulation, induction, space-charge

17

D.A. Starostenko
BINP SB RAS, Novosibirsk, Russia

X-ray complexes based on a linear induction accelerator are designed to study of high density objects. It requires of high-current electron beam to obtain a small spot and bright x-ray source using a conversion target. The electrons source in such installations is injectors capable generate pulses with a duration from tens of nanoseconds to several microseconds and a current of several kiloamperes. The transportation and focusing such beams into diameter about 1 mm is difficult due to of the space charge effect. In similar induction accelerators (DARHT, AIRIX, FXR, etc.), auto-emission cathodes are used to obtain high-current electron beams. The use of a thermionic cathode, in compared to auto-emission cathode, provides stable generation of several pulses with a time interval of several microseconds, but makes high requirements on the injector vacuum system: not less than 10^-7 Torr.

Slides MOY05 [3.946 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-MOY05

About •

Received ※ 24 September 2021 — Revised ※ 05 October 2021 — Accepted ※ 13 October 2021 — Issued ※ 23 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPSA53

Focusing Properties of the Magnetic Structure of Isochronous Cyclotrons With Large Spiraling Angle of Pole Tips

cyclotron, ECR, factory, H-minus

219

D.A. Amerkanov, S.A. Artamonov, E.M. Ivanov, G.A. Riabov, V.A. Tonkikh
PNPI, Gatchina, Leningrad District, Russia

Magnetic structures with a high spiraling angle of pole tips are used in superconducting cyclotrons, H⁻ ion cyclotrons, etc. and they have been investigated in a number of works. In connection with the design of an 80 MeV isochronous H⁻ cyclotron, such studies were continued and extended. The paper proposes a relatively simple approach for analyzing the projected spiral structure. The main conclusions can be formulated as follows. The introduction of spiraling makes it possible to significantly increase the vertical focusing, but in the central region at radii smaller than the gap in the hills, the structure with high spiraling angle becomes ineffective and can lead to a decrease in focusing. Each radius can be associated with a limiting spirality angle, above which spiraling leads to a resultant decrease in vertical focusing. The spiraling of the magnetic field does not coincide with the geometric spiraling of the pole tips, which should be taken into account when designing the cyclotron structure. The developed technique can be useful for a quick analysis of various options and will reduce the amount of time-consuming calculations by using 3D programs.

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-MOPSA53

About •

Received ※ 07 September 2021 — Accepted ※ 10 September 2021 — Issued ※ 15 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPSB08

Magneto-Optical Structure of the NICA Collider With High Critical Energy

quadrupole, sextupole, dynamic-aperture, collider

245

S.D. Kolokolchikov, V. Senichev
RAS/INR, Moscow, Russia
E. Syresin
JINR, Dubna, Moscow Region, Russia

In the proton option of the NICA collider, there is a problem of crossing transition energy. To do this, we have investigated ways to increase the critical energy for the proton option of the NICA collider. The method of superperiodic modulation of quadrupole gradients is applied. Two variants of dispersion suppression on the arch for matching with straight sections are considered. The selection of sextupoles is carried out to suppress the natural chromaticity and compensate for the sextupole component. The Twiss parameters for the proposed structures are given, as well as the dynamic apertures and working points are investigated.

Poster TUPSB08 [3.646 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-TUPSB08

About •

Received ※ 17 September 2021 — Revised ※ 27 September 2021 — Accepted ※ 02 October 2021 — Issued ※ 21 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPSB39

Study of Space Charge Compensation Process of a 400 KeV Pulsed Hydrogen Ion Beam

electron, space-charge, plasma, ion-source

313

A. Belov, O.T. Frolov, S.A. Gavrilov, L.P. Nechaeva, A.V. Turbabin, V. Zubets
RAS/INR, Moscow, Russia

Funding: Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, Russia
A three grid energy analyzer of slow secondary ions with a twin analyzing grid is described. The analyzer has cylindrical geometry and Pi angle for recording of the slow ions. The analyzer has been used for measurements of degree of space-charge compensation (SCC) of a pulsed hydrogen ion beam with energy of 400 keV and peak beam current of 60 mA. Results of the measurements are presented and compared with theoretical estimations based on model in which the SCC degree is limited by heating of electrons in collisions with fast ions of the beam.

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-TUPSB39

About •

Received ※ 20 September 2021 — Revised ※ 05 October 2021 — Accepted ※ 09 October 2021 — Issued ※ 16 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPSC17

Vibrating Wire System for Fiducialization NICA Booster Superconducting Quadrupole Magnets

quadrupole, booster, collider, synchrotron

379

T. Parfylo, M.A. Kashunin, V.A. Mykhailenko
JINR/VBLHEP, Dubna, Moscow region, Russia
V.V. Borisov, H.G. Khodzhibagiyan, B.Yu. Kondratiev, S.A. Kostromin, M.M. Shandov
JINR, Dubna, Moscow Region, Russia

The NICA (Nuclotron-based Ion Collider fAcility) is anew accelerator complex under construction at the the Laboratory of High Energy Physics (LHEP) JINR. The facility includes two injector chains, two existing superconducting synchrotrons Nuclotron and a new Booster, under construction superconducting Collider, consisting of two rings. The lattice of the Booster includes 48 superconducting quadrupole magnets that combined in doublets. Each doublet must be fiducialized to the calculated trajectory of the beam. Alignment of the magnetic axis is necessary for properly install the magnets at the beam trajectory. The vibrating wire technique was applied to obtain the position of the magnetic axis. A new measurement system has been worked out and produced at the LHEP. The magnetic axis positions of the quadrupole doublets are determined at the ambient temperature. Thepaper describes design of the measurement system, measuring procedure and results of the magnetic axis position measurements.

Poster WEPSC17 [0.693 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-WEPSC17

About •

Received ※ 28 September 2021 — Revised ※ 29 September 2021 — Accepted ※ 09 October 2021 — Issued ※ 22 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPSC30

Measurement of the Phase Portrait of a 2 MeV Proton Beam Along Beam Transfer Line

proton, neutron, emittance, target

399

T.A. Bykov
Budker INP & NSU, Novosibirsk, Russia
Ia.A. Kolesnikov, S.Yu. Taskaev
NSU, Novosibirsk, Russia
Ia.A. Kolesnikov, I.M. Shchudlo, S.Yu. Taskaev
BINP SB RAS, Novosibirsk, Russia
S. Savinov
BINP, Novosibirsk, Russia

Funding: The research was supported by Russian Science Foundation, grant No. 19-72-30005.
For the development of boron neutron capture therapy - an accelerator source of epithermal neutrons has been proposed and created at the Budker Institute of Nuclear Physics (Novosibirsk, Russia). For future therapy it is necessary to ensure the transportation of a proton beam in a high-energy beam line at a distance of 10 meters. For this purpose, using a movable diaphragm with a diameter of 1 mm, mounted on a three-dimensional vacuum manipulator, and a wire scanner, the phase portrait of the proton beam was measured. The software for remote control of the movable diaphragm and data processing of the wire scanner was developed. An algorithm for processing a series of measurements was developed to reconstruct the image of the phase portrait of the beam and calculate the emittance. This work describes in detail the features of the measuring devices, control algorithms and data processing. An experiment was carried out to measure the phase portrait and emittance of a proton beam with an energy of 2 MeV and a current of up to 3 mA. A beam of neutral particles was also measured. The effect of a bending magnet on the focusing and emittance of the beam is studied. The invariant normalized emittances calculated from the measured phase portraits make it possible to assert that the beam can be transported over distances of about 10 meters without changes in the current geometry of the high-energy beam line.

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-WEPSC30

About •

Received ※ 10 September 2021 — Revised ※ 22 September 2021 — Accepted ※ 23 September 2021 — Issued ※ 11 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRA03

Simulation and Design of the Permanent Magnet Multipole for DC140

simulation, dipole, factory, permanent-magnet

99

V.P. Kukhtin, A.A. Firsov, M. Kaparkova, E.A. Lamzin, M.S. Larionov, A. Makarov, A. Nezhentzev, I.Yu. Rodin, N. Shatil
NIIEFA, St. Petersburg, Russia
N.S. Edamenko, D.A. Ovsyannikov
St. Petersburg State University, St. Petersburg, Russia
G.G. Gulbekyan, I.A. Ivanenko, I.V. Kalagin, N.Yu. Kazarinov, N.F. Osipov
JINR, Dubna, Moscow Region, Russia
S.E. Sytchevsky
Saint Petersburg State University, Saint Petersburg, Russia

Permanent magnet (PM) multipoles in some cases are good candidates in accelerator applications for beam transportation and focusing. The PM quadrupole will be utilized in the DC140 cyclotron which is under construction in JINR. A passive magnetic channel and a PM quad will be used for the compensation of horizontal defocusing in the high and low field regions, respectively. The quad is designed as a set of identical PMs rigidly fixed in a non-magnetic housing and capable to generate a a 8.1 T/m gradient field in the 64x25 mm aperture and 29.926 cm effective length. The error of linear approximation should be 1% or less. A special study was accomplished to define the PM specification reasoning from the demand for desired field strength, simple geometry, minimized nomenclature, and commercial availability. The quad design was selected with the use a 2D analytical model and then optimized in iterative 3D FE simulations with realistic PM shape and magnetic characteristics in mind. The resultant concept is the quad formed with 6 coaxial sections each 5cm in width. Every section has 26 identical PM bricks with the dimensions 11mmx11mmx50mm and different orientations. The PM bricks have remanent induction of 1.185 T and magnetic susceptibility of 0.1. Temperature characteristics and expected lifetime were also analysed. From the results obtained, candidate PM materials were proposed and mechanical and magnetic precision were recommended.

Slides FRA03 [1.465 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRA03

About •

Received ※ 09 September 2021 — Accepted ※ 29 September 2021 — Issued ※ 12 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRB03

Upgrated the Extraction Device of Focused Electron Beam Into the Atmosphere

electron, extraction, cathode, permanent-magnet

114

E.V. Domarov, I. Chakin, V.G. Cherepkov, S. Fadeev, M. Golkovsky, Yu.I. Golubenko, A.I. Korchagin, N.K. Kuksanov, A. Lavrukhin, P.I. Nemytov, R.A. Salimov, A.V. Semenov
BINP SB RAS, Novosibirsk, Russia

For over 30 years, an extraction device has been successfully working in BINP at the ELV-6 accelerator to extract a focused beam of electrons into the atmosphere. The accelerating tube with permanent magnetic lenses was used in this installation. The design of these accelerator tubes with magnetic lenses is rather complicated. Recently, simpler design and high reliability accelerating tubes with big aperture is operating in ELV accelerators. For this reason, the problem number one at present is to develop the extraction device, capable of reliably working with serial accelerator tubes, of the ELV accelerator with power up to100 kW. The lens L1 is located directly at the lower end of the accelerating tube. Passing the lens L1, the beam is focused near the diaphragm D6 and increases to a diameter of 10 mm in the diaphragm D5. For passing the beam along the axis of the diaphragms, there are corrections coils C1 C2 C3. The diameter of diaphragm hole D1 is the most critical, because it determines the flow of gas that should be pumped out in the following steps of the vacuum system. Measurements of the parameters of a high-power electron beam were carried out up to a power of 100 kW. As a result of the made experiments the minimum diameter of the beam at the exit from the extractions device has been 2 mm at the energy of 1,4 MeV and the beam current of 60 mA.

Slides FRB03 [2.785 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRB03

About •

Received ※ 02 September 2021 — Revised ※ 15 September 2021 — Accepted ※ 23 September 2021 — Issued ※ 19 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRB04

A Linear Accelerator for Proton Therapy

linac, proton, acceleration, operation

117

V.V. Paramonov, A.P. Durkin, A. Kolomiets
RAS/INR, Moscow, Russia

For applications in proton therapy, linear accelerators can provide beam performances not achievable with cyclic facilities. The results of the development of a proposal for a linac with the maximal proton energy of 230 MeV are presented. Operating in a pulsed mode, with a repetition rate not less than 50 Hz, the linac is designed to accelerate up to 10¹³ protons per irradiation cycle lasting from 10 to 200 seconds. Possibilities of fast, from pulse to pulse, adjustment of the output energy in the range from 60 MeV to 230 MeV, formation and acceleration to the output energy of a "pencil-like" beam with a diameter of ~ 2 mm are shown. Optimized solutions, proposed for both the accelerating-focusing channel and the technical systems of the linac make it possible to create a facility with high both target and technical and economic features. Special attention, due to the selection of proven in long-term operation parameters of the systems, is paid to ensuring the reliability of the linac operation. The feasibility of linac is substantiated on the basis of mastered or modified with a guarantee industrial equipment.

Slides FRB04 [5.370 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-RuPAC2021-FRB04

About •

Received ※ 16 September 2021 — Revised ※ 30 September 2021 — Accepted ※ 09 October 2021 — Issued ※ 13 October 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)