RuPAC2014 - Classification: 08 Magnetic and vacuum systems, power supplies

Paper

Title

Page

Ultrahigh Vacuum in Superconducting Synchrotrons

23

A.V. Smirnov, A.V. Butenko, A.R. Galimov
JINR, Dubna, Moscow Region, Russia
A.M. Bazanov, A. Nesterov
JINR/VBLHEP, Dubna, Moscow region, Russia

The achievement of ultrahigh vacuum conditions in the range of 10^-10 – 10^-12 Torr is a very complicate task for charged particle accelerators. For superconducting accelerators the main rest gas is hydrogen which does not freeze effectively on the chamber wall even under the liquid helium temperature. Fast ramp of the magnetic field in the superconducting synchrotrons leads to the heating of the vacuum chamber that brings an additional problem for the achievement of the ultrahigh vacuum. In this talk the review of ultrahigh vacuum systems in superconducting accelerators is presented. Non-evaporated getters under the liquid nitrogen temperature are planned to the achievement of necessary vacuum conditions in the new accelerator complex of the NICA project (JINR, Russia).

Slides TUCB01 [2.220 MB]

TUPSA29

Method of Broadband Stabilization of the VEPP-4M Main Field

100

A.V. Pavlenko, A.M. Batrakov, G.V. Karpov, I.B. Nikolaev, V.V. Svishchev
BINP SB RAS, Novosibirsk, Russia
A.V. Pavlenko
NSU, Novosibirsk, Russia

Funding: Ministry of Education and Science of the Russian Federation, NSh-4860.2014.2
The stability of the main field has great influence on precision experiments on particle physics which are performed on VEPP-4M facility currently. A method of broadband stabilization of the VEPP-4M main field allowing us to achieve field stability better than 0.5 ppm over DC - 50Hz frequency range is presented. The method combines NMR stabilization and feedback loop using induction signal.

TUPSA30

Analysis of the Magnetic Field Distribution of PMQ Lenses for PRIOR Setup

V.A. Panyushkin, A.V. Bogdanov, A. Golubev, A.V. Kantsyrev, V. Skachkov
ITEP, Moscow, Russia
A. Golubev
MEPhI, Moscow, Russia
P.M. Lang, M.E. Rodionova, L. Shestov, D. Varentsov, K. Weyrich
GSI, Darmstadt, Germany

Funding: Joint Helmholtz-ROSATOM FAIR-Russia Research Centre (HGF-IVF-IK-Ru-002)
As part of the FAIR project, HEDgeHOB collaboration involves developments of PRIOR* proton-radiographic facilities, one of the purposes of which is to study the state of matter in extreme conditions. In the currently in GSI (Darmstadt, Germany), prototype of PRIOR proton microscope setup is developing, this setup designed for the use of proton beam with energy of 4.5 GeV. Magnetic optics of PRIOR proton microscope forming section consists of four quadrupole lenses created on the basis of permanent magnets (PMQ). For best quality (linearity, magnetic axis position, angle of median plane) of the magnetic field of quadrupole lenses and a full-scale setup simulation is necessary to measure the magnetic field inside the lenses. For the measurement of the magnetic field (radial component of the magnetic field) of quadrupole lenses are designed and developed magnetic field scanner. Scanning of the magnetic field is performed on cylindrical surface near the inner surface of PMQ lenses. Based on the results of scanning the radial component of the magnetic field will be carried out calculations of the mathematical model (developed in ITEP)**, which describes the distribution of the magnetic field at any point within the aperture of the lens. In this work presents the results of the calculation of all components of the magnetic field, determining the position of the magnetic axis,harmonic analysis and the analysis of non-linearity of the magnetic field for PRIOR PMQ lenses.
*D. Varenstov et.al.; PRIOR for GSI and for FAIR; 4th International Workshop on HEPM, 2013
**V.S. Skachkov et.al.; REPM Quadrupole for Proton Microscopy; 2th International Workshop on HEPM, 2010

TUPSA31

Magnetic System of Isochronous Cyclotron F250 for Proton Therapy Applications

103

Yu.G. Alenitsky, E. Samsonov
JINR, Dubna, Moscow Region, Russia
N.L. Zaplatin
JINR/DLNP, Dubna, Moscow region, Russia

In the Laboratory of Nuclear Problems of the JINR the possibility of designing of the isochronous cyclotron F250 with the energy of protons 250 MeV on the basis of magnet with the diameter of pole 6 m, which is used for the synchro-cyclotron is examined. Synchro-cyclotron many years works for obtaining the protons with the energy 680 MeV and with the intensity of extracted beam 2.5 mkA. For the solution of medical problems the required energy of protons comprises not more than 250 MeV and depends on the depth of the tumor arrangement inside a patient. For determining the required energy of protons the information about the mean free path of protons in the correspondence for the position of Bragg's peak in each case is used. Necessary energy of protons is obtained by means of degrader system providing a retarding the extracted beam of protons with 680 MeV to 250 MeV and less. In this case the utilized for medical purposes intensity of beam does not exceed 50 nA. The proposed cyclotron F250 will make it possible to strongly decrease the electric power of magnet and to avoid the need of beam degradation from 680 MeV to 250 MeV. For creating the required magnetic field of the cyclotron F250 it is necessary to change the form of steel spiral shims and disks, located inside a vacuum chamber of synchro-cyclotron. The basic parameters of the magnetic system of the cyclotron F250 with the condition of retaining the vacuum chamber and the magnet yoke of synchro-cyclotron are given.

TUPSA32

Magnetic Field Design and Calculation for the FLNR DC-280 Cyclotron

105

I.A. Ivanenko, B. Gikal, G.G. Gulbekyan
JINR, Dubna, Moscow Region, Russia
T.F. Belyakova, V.P. Kukhtin, E.A. Lamzin, S.E. Sytchevsky
NIIEFA, St. Petersburg, Russia

The isochronous cyclotron DC-280 is intended to accelerate the ion beams with A/Z from 4 to 7 up to the energy 8 – 4 MeV/nucleon. The wide range of the magnetic field levels from 0.64T till 1.32T allows to make a smooth variation of the beam energy over the range ±50% from nominal. For operational optimization of the magnetic field the 11 radial and 4 pairs of harmonic correcting coils are used. The numerical formation of the magnetic field is carried out. The problems and solutions of DC-280 magnetic field design are described.

TUPSA33

Horizontal Klystron Cathode Heater Power Supply System for the European XFEL

P.A. Bak, A.A. Korepanov, A.V. Ottmar, N.A. Zolotukhina
BINP SB RAS, Novosibirsk, Russia
A. Cherepenko, V. Vogel
DESY, Hamburg, Germany

The European XFEL project will employ L-band multibeam horizontal klystrons (MBK) from companies Toshiba (E3736) and Thales (TH 1802). Using the horizontal type of klystrons will significantly reduce construction costs of XFEL tunnel, but due to the large weights and dimensions of the pulse transformers and klystrons requires far more complicated mechanism to connect the klystrons and the pulse transformers inside the tunnel. It was proposed to make these connections by using flexible HV cable. BINP has developed an intermediate oil tank, connection module (CM), which on one side is connected to the cathode of klystron and on the other side has a HV connector for the connection to the pulse transformer. The connection module mechanically consists of two assemblies. The first is the oil tank that has inside an insulated filament transformer and measurement system. The second is the high frequency power supply unit (HFPS) what can be up to 20 meters away from the oil tank. The insulating transformer is designed by unique technology of the coupled resonant circuits with a high-voltage gap of 49 mm and coupling factor ~0.6. Its working frequency is about 1.6 kHz. The efficiency is gained about 90%, and maximum electric field intensity does not exceed 35 kV/cm. In this paper we give an overview of the design and the test results of the horizontal klystron cathode heater power supply system based on using HV insulating transformer with coupling factor <1.

TUPSA34

The Power Supply System of Electrostatic Deflecting Plates for Accelerating Complex NICA

108

A.A. Fateev, E.V. Gorbachev, N.I. Lebedev
JINR, Dubna, Moscow Region, Russia

Three pairs of electrostatic deflecting plates will be placed in the booster ring. They will provide injection of heavy ion beam into the Booster. The power supply system for one plate providing all necessary parameters including suppression of the afterpulses is described in the report. The calculated and experimental results are also presented.

TUPSA35

Virtual Laboratory of Vacuum Technique

110

G.P. Averyanov, V.V. Dmitriyeva, V.L. Shatokhin
MEPhI, Moscow, Russia

The report considers the interactive computer modeling of vacuum systems. Operation of real vacuum installations is modeled by simulating computer code. It becomes possible in a short time (with the assessment of real-time) to pass through full cycle of the technologies to reach high vacuum state and to estimate the necessary time. It is possible to assemble virtual installation, to choose the necessary pumps (from the database of low-vacuum and high-vacuum ones), to select the vacuum connecting pipes with the required parameters. The vacuum chamber volume and its internal surfaces characteristics (roughness, types of preliminary processing), defining outgassing from these surfaces are set. Possible leakage in junction places of the individual elements of the system could be taken into consideration. After pumping start, sequential switching on of different pumps and achievement of a certain pressure, possibility of chamber preheating up to the necessary temperature is provided. During the analysis of procedure of pumping optimization of the structure of system and the selected elements is made. The computer laboratory is a part of traditional laboratory of vacuum technique of the Department of Electrophysical Facilities of NRNU MEPhI. Modeling of vacuum systems significantly expands the functional capabilities of this laboratory.

Paper	Title	Page
TUCB01	Ultrahigh Vacuum in Superconducting Synchrotrons	23
	A.V. Smirnov, A.V. Butenko, A.R. Galimov JINR, Dubna, Moscow Region, Russia A.M. Bazanov, A. Nesterov JINR/VBLHEP, Dubna, Moscow region, Russia
	The achievement of ultrahigh vacuum conditions in the range of 10^-10 – 10^-12 Torr is a very complicate task for charged particle accelerators. For superconducting accelerators the main rest gas is hydrogen which does not freeze effectively on the chamber wall even under the liquid helium temperature. Fast ramp of the magnetic field in the superconducting synchrotrons leads to the heating of the vacuum chamber that brings an additional problem for the achievement of the ultrahigh vacuum. In this talk the review of ultrahigh vacuum systems in superconducting accelerators is presented. Non-evaporated getters under the liquid nitrogen temperature are planned to the achievement of necessary vacuum conditions in the new accelerator complex of the NICA project (JINR, Russia).
	Slides TUCB01 [2.220 MB]

TUPSA29	Method of Broadband Stabilization of the VEPP-4M Main Field	100
	A.V. Pavlenko, A.M. Batrakov, G.V. Karpov, I.B. Nikolaev, V.V. Svishchev BINP SB RAS, Novosibirsk, Russia A.V. Pavlenko NSU, Novosibirsk, Russia
	Funding: Ministry of Education and Science of the Russian Federation, NSh-4860.2014.2 The stability of the main field has great influence on precision experiments on particle physics which are performed on VEPP-4M facility currently. A method of broadband stabilization of the VEPP-4M main field allowing us to achieve field stability better than 0.5 ppm over DC - 50Hz frequency range is presented. The method combines NMR stabilization and feedback loop using induction signal.

TUPSA30	Analysis of the Magnetic Field Distribution of PMQ Lenses for PRIOR Setup
	V.A. Panyushkin, A.V. Bogdanov, A. Golubev, A.V. Kantsyrev, V. Skachkov ITEP, Moscow, Russia A. Golubev MEPhI, Moscow, Russia P.M. Lang, M.E. Rodionova, L. Shestov, D. Varentsov, K. Weyrich GSI, Darmstadt, Germany
	Funding: Joint Helmholtz-ROSATOM FAIR-Russia Research Centre (HGF-IVF-IK-Ru-002) As part of the FAIR project, HEDgeHOB collaboration involves developments of PRIOR* proton-radiographic facilities, one of the purposes of which is to study the state of matter in extreme conditions. In the currently in GSI (Darmstadt, Germany), prototype of PRIOR proton microscope setup is developing, this setup designed for the use of proton beam with energy of 4.5 GeV. Magnetic optics of PRIOR proton microscope forming section consists of four quadrupole lenses created on the basis of permanent magnets (PMQ). For best quality (linearity, magnetic axis position, angle of median plane) of the magnetic field of quadrupole lenses and a full-scale setup simulation is necessary to measure the magnetic field inside the lenses. For the measurement of the magnetic field (radial component of the magnetic field) of quadrupole lenses are designed and developed magnetic field scanner. Scanning of the magnetic field is performed on cylindrical surface near the inner surface of PMQ lenses. Based on the results of scanning the radial component of the magnetic field will be carried out calculations of the mathematical model (developed in ITEP)*, which describes the distribution of the magnetic field at any point within the aperture of the lens. In this work presents the results of the calculation of all components of the magnetic field, determining the position of the magnetic axis,harmonic analysis and the analysis of non-linearity of the magnetic field for PRIOR PMQ lenses. D. Varenstov et.al.; PRIOR for GSI and for FAIR; 4th International Workshop on HEPM, 2013 **V.S. Skachkov et.al.; REPM Quadrupole for Proton Microscopy; 2th International Workshop on HEPM, 2010

TUPSA31	Magnetic System of Isochronous Cyclotron F250 for Proton Therapy Applications	103
	Yu.G. Alenitsky, E. Samsonov JINR, Dubna, Moscow Region, Russia N.L. Zaplatin JINR/DLNP, Dubna, Moscow region, Russia
	In the Laboratory of Nuclear Problems of the JINR the possibility of designing of the isochronous cyclotron F250 with the energy of protons 250 MeV on the basis of magnet with the diameter of pole 6 m, which is used for the synchro-cyclotron is examined. Synchro-cyclotron many years works for obtaining the protons with the energy 680 MeV and with the intensity of extracted beam 2.5 mkA. For the solution of medical problems the required energy of protons comprises not more than 250 MeV and depends on the depth of the tumor arrangement inside a patient. For determining the required energy of protons the information about the mean free path of protons in the correspondence for the position of Bragg's peak in each case is used. Necessary energy of protons is obtained by means of degrader system providing a retarding the extracted beam of protons with 680 MeV to 250 MeV and less. In this case the utilized for medical purposes intensity of beam does not exceed 50 nA. The proposed cyclotron F250 will make it possible to strongly decrease the electric power of magnet and to avoid the need of beam degradation from 680 MeV to 250 MeV. For creating the required magnetic field of the cyclotron F250 it is necessary to change the form of steel spiral shims and disks, located inside a vacuum chamber of synchro-cyclotron. The basic parameters of the magnetic system of the cyclotron F250 with the condition of retaining the vacuum chamber and the magnet yoke of synchro-cyclotron are given.

TUPSA32	Magnetic Field Design and Calculation for the FLNR DC-280 Cyclotron	105
	I.A. Ivanenko, B. Gikal, G.G. Gulbekyan JINR, Dubna, Moscow Region, Russia T.F. Belyakova, V.P. Kukhtin, E.A. Lamzin, S.E. Sytchevsky NIIEFA, St. Petersburg, Russia
	The isochronous cyclotron DC-280 is intended to accelerate the ion beams with A/Z from 4 to 7 up to the energy 8 – 4 MeV/nucleon. The wide range of the magnetic field levels from 0.64T till 1.32T allows to make a smooth variation of the beam energy over the range ±50% from nominal. For operational optimization of the magnetic field the 11 radial and 4 pairs of harmonic correcting coils are used. The numerical formation of the magnetic field is carried out. The problems and solutions of DC-280 magnetic field design are described.

TUPSA33	Horizontal Klystron Cathode Heater Power Supply System for the European XFEL
	P.A. Bak, A.A. Korepanov, A.V. Ottmar, N.A. Zolotukhina BINP SB RAS, Novosibirsk, Russia A. Cherepenko, V. Vogel DESY, Hamburg, Germany
	The European XFEL project will employ L-band multibeam horizontal klystrons (MBK) from companies Toshiba (E3736) and Thales (TH 1802). Using the horizontal type of klystrons will significantly reduce construction costs of XFEL tunnel, but due to the large weights and dimensions of the pulse transformers and klystrons requires far more complicated mechanism to connect the klystrons and the pulse transformers inside the tunnel. It was proposed to make these connections by using flexible HV cable. BINP has developed an intermediate oil tank, connection module (CM), which on one side is connected to the cathode of klystron and on the other side has a HV connector for the connection to the pulse transformer. The connection module mechanically consists of two assemblies. The first is the oil tank that has inside an insulated filament transformer and measurement system. The second is the high frequency power supply unit (HFPS) what can be up to 20 meters away from the oil tank. The insulating transformer is designed by unique technology of the coupled resonant circuits with a high-voltage gap of 49 mm and coupling factor ~0.6. Its working frequency is about 1.6 kHz. The efficiency is gained about 90%, and maximum electric field intensity does not exceed 35 kV/cm. In this paper we give an overview of the design and the test results of the horizontal klystron cathode heater power supply system based on using HV insulating transformer with coupling factor <1.

TUPSA34	The Power Supply System of Electrostatic Deflecting Plates for Accelerating Complex NICA	108
	A.A. Fateev, E.V. Gorbachev, N.I. Lebedev JINR, Dubna, Moscow Region, Russia
	Three pairs of electrostatic deflecting plates will be placed in the booster ring. They will provide injection of heavy ion beam into the Booster. The power supply system for one plate providing all necessary parameters including suppression of the afterpulses is described in the report. The calculated and experimental results are also presented.

TUPSA35	Virtual Laboratory of Vacuum Technique	110
	G.P. Averyanov, V.V. Dmitriyeva, V.L. Shatokhin MEPhI, Moscow, Russia
	The report considers the interactive computer modeling of vacuum systems. Operation of real vacuum installations is modeled by simulating computer code. It becomes possible in a short time (with the assessment of real-time) to pass through full cycle of the technologies to reach high vacuum state and to estimate the necessary time. It is possible to assemble virtual installation, to choose the necessary pumps (from the database of low-vacuum and high-vacuum ones), to select the vacuum connecting pipes with the required parameters. The vacuum chamber volume and its internal surfaces characteristics (roughness, types of preliminary processing), defining outgassing from these surfaces are set. Possible leakage in junction places of the individual elements of the system could be taken into consideration. After pumping start, sequential switching on of different pumps and achievement of a certain pressure, possibility of chamber preheating up to the necessary temperature is provided. During the analysis of procedure of pumping optimization of the structure of system and the selected elements is made. The computer laboratory is a part of traditional laboratory of vacuum technique of the Department of Electrophysical Facilities of NRNU MEPhI. Modeling of vacuum systems significantly expands the functional capabilities of this laboratory.