2011 Particle Accelerator Conference - List of Keywords (cyclotron)

Paper	Title	Other Keywords	Page
MOOBN3	Comparison of Accelerator Technologies for use in ADSS	target, proton, linac, SRF	4
	W.-T. Weng, H. Ludewig, D. Raparia, M. Todosow, D. Trbojevic BNL, Upton, Long Island, New York, USA P.M. McIntyre, A. Sattarov Texas A&M University, College Station, Texas, USA
	Funding: Work performed under the auspices of the US Department of Energy Accelerator Driven Subcritical (ADS) fission is an interesting candidate basis for nuclear waste transmutation and for nuclear power generation. ADS can use either thorium or depleted uranium as fuel, operate below criticality, and consume rather than produce long-lived actinides. A case study with a hypothetical, but realistic nuclear core configuration is used to evaluate the performance requirements of the driver proton accelerator in terms of beam energy, beam current, duty factor, beam distribution delivered to the fission core, reliability, and capital and operating cost. Comparison between a CW IC and that of an SRF proton linac is evaluated. Future accelerator R&D required to improve each candidate accelerator design is discussed.
	Slides MOOBN3 [1.540 MB]

MOP051	End-to-End Simulation of an Inverse Cyclotron for Muon Cooling	simulation, emittance, injection, collider	193
	K. Paul, E. Cormier-Michel Tech-X, Boulder, Colorado, USA T. Hart, D.J. Summers UMiss, University, Mississippi, USA
	Funding: DOE Office of High-Energy Physics, SBIR DE-FG02-08ER85044 Neutrino factories and muon colliders require significant cooling of the muon beam. Most muon cooling channels are long and expensive single-pass structures, due to the difficulty injecting very large emittance beams into a circular device. Inverse cyclotrons can potentially solve the injection problems associated with other circular cooling channels, and they can potentially provide substantial initial cooling of the beam. We present the first end-to-end (injection to extraction) simulations of an inverse cyclotron for muon cooling, performed with the particle-in-cell code VORPAL. We study the cooling capability of the device as well as potential limitations due to space charge effects and material interactions with the beam.

MOP228	TE Wave Measurements of the Electron Cloud in a Dipole Magnetic Field	electron, resonance, plasma, dipole	531
	S. De Santis, J.M. Byrd LBNL, Berkeley, California, USA J.R. Calvey, J. Joseph, J.A. Livezey, J.P. Sikora, K.G. Sonnad CLASSE, Ithaca, New York, USA K.C. Hammond Harvard University, Cambridge, Massachusetts, USA
	Funding: Work supported by the U.S. Department of Energy under Contract Nos. DE-AC02-05CH1123 and DE-FC02-08ER41538 and by the National Science Foundation Grant PHY-0734867. The TE wave propagation method has become a widely used technique for measuring electron cloud density in an accelerator beampipe. In most instances the wave very low power is not capable of affecting the low-energy electrons distribution. During experiments in the CESR Damping Ring Test Accelerator (Cesr-TA), we have observed a particular situation where a resonance between the wave and a dipole magnetic field produces a large modification in the electron cloud distribution that can be measured by other detectors. We believe this resonance is strongly dependent on the geometry of standing waves pattern that discontinuities in the beampipe generate. We present measurements in Cesr-TA, which describe the effect and are in support of our hypothesis.

WEP190	Magnetic Field Expansion Out of a Plane: Application to Cyclotron Development	vacuum, simulation, focusing, factory	1846
	T. Hart, D.J. Summers UMiss, University, Mississippi, USA K. Paul Tech-X, Boulder, Colorado, USA
	In studies of the dynamics of charged particles in a cyclotron magnetic field, the specified field is generally Bz in the z = 0 midplane where Br and Btheta are zero. Br(r,theta, z) and Btheta (r,theta, z) are usually determined through a linear expansion which assumes that Bz is independent of z. An expansion to only first order may not be sufficient for orbit simulations at small r and large z. This paper reviews the expansion of a specified Bz(r,theta, z = 0) out of the z = 0 midplane to arbitrary order, and shows simple examples worked out to 4th order.

WEP231	TRIUMF Cyclotron Beam Quality Improvement	extraction, TRIUMF, emittance, beam-losses	1921
	I.V. Bylinskii, R.A. Baartman, F.W. Bach, J.F. Cessford, G. Dutto, Y.-N. Rao, L.W. Root, R. Ruegg TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	TRIUMF cyclotron for decades operated at 500 MeV. Recently, the two primary beamlines 1A and 2A, have been reconfigured for running at 480 MeV. The objective was to reduce beam losses caused by the electromagnetic stripping by 30%. The radiation losses reduction was confirmed with both online measurements and residual activation field mapping after 8 month of beam production. In order to improve stability of both primary beams, one of the harmonic coils was configured in Bz-mode to compensate for the beam split ratio fluctuations. Br-mode of this coil and two outer radius trim coils was utilized to correct the beam vertical position at extraction. Moreover, to make the beam spot position on the target stable and insensitive to any uncontrolled movement of the stripper foil due to heat distortion, the beamline front end optics was tuned to compensate the cyclotron's inherent dispersion. Details of these developments and improvements are discussed in the paper.

WEP232	A Multi Megawatt Ring Cyclotron to Search for CP Violation in the Neutrino Sector	extraction, injection, cavity, proton	1924
	L. Calabretta, M.M. Maggiore, D. Rifuggiato INFN/LNS, Catania, Italy A. Calanna CSFNSM, Catania, Italy L.A.C. Piazza INFN/LNL, Legnaro (PD), Italy
	A new approach to search for CP violation in the neutrino sector* is proposed by the experiment called DAEδALUS (Decay At rest Experiment for cp At Laboratory for Underground Science). DAEδALUS needs three sources of neutrino fluxes, each one located at 1.5, 8 and 20 km from the underground detector. Each source has to be supplied with a proton beam with power higher than 1, 2 and 5 MW respectively. Here we present the study for a Superconducting Ring Cyclotron able to accelerate the H²⁺ molecules and to deliver proton beam with maximum energy of 800 MeV and the required power. Although the average power for the first 2 sites are 1 and 2 MW, the 20% duty cycle, required by the experiment, has the consequence that the peak power should stay in the range 5-10 MW and a peak current of about 4.5 mA of H²⁺ is necessary. We present the parameters of the superconducting magnetic sector simulated by the code TOSCA, the isochronous magnetic field produced and the magnetic forces acting on the coils. Some evaluation on the feasibility of the ring cyclotron, the advantages and problems relates with acceleration of the H²⁺ molecules will be also presented. * J. Alonso et al., “Expression of Interest for a Novel Search for CP Violation in the Neutrino Sector: DAEδALUS”, Jun 2010. e-Print: arXiv:1006.0260

WEP237	The Oak Ridge Isochronous Cyclotron Refurbishment Project	extraction, ion, ISOL, vacuum	1930
	A.J. Mendez, J.B. Ball, D. Dowling, S.W. Mosko, B.A. Tatum ORNL, Oak Ridge, Tennessee, USA
	Funding: Managed by UT-Battelle, LLC for the U.S. Department of Energy under contract DE-AC05-00OR22725. The Oak Ridge Isochronous Cyclotron (ORIC) has been in operation for nearly fifty years at the Oak Ridge National Laboratory (ORNL). Presently, it serves as the driver accelerator for the ORNL Holifield Radioactive Ion Beam Facility (HRIBF), where beams are produced using the Isotope Separation Online (ISOL) technique for post-acceleration by the HRIBF 25URC tandem accelerator. Operability and reliability of ORIC are critical issues for the success of HRIBF and have presented increasingly difficult operational challenges for the facility in recent years. Earlier this year, a trim coil failure rendered ORIC inoperable for several months. This presented HRIBF with the opportunity to undertake various repairs and maintenance upgrades aimed at restoring the full functionality of ORIC and improving the reliability to a level better than what had been typical over the previous decade. In this paper, we present details of these efforts, including the replacement of the entire trim coil set and measurements of their radial field profile. Comparison of measurements and operating tune parameters with setup code predictions will also be presented.

THOCN6	Flux-coupled Cyclotron Stack: Optimization for Maximum Beam Power and Minimum Losses	cavity, coupling, injection, extraction	2113
	P.M. McIntyre, A. Sattarov Texas A&M University, College Station, Texas, USA
	Funding: This work was supported in part by the U.S. Department of Energy under Grant DE-FG02-06ER41405 A flux-coupled stack of isochronous cyclotrons has been proposed as a driver for Accelerator-Driven Subcritical Systems (ADSS) for thorium-cycle fission power. The issues that limit beam current and phase space brightness are evaluated, including space charge tune shift, synchro-betatron coupling, orbit separation at injection and extraction, RF propagation within the accelerator envelope, RF parasitic modes, and stability of electrostatic septum operation. A design is presented that offers good optimization of these criteria.
	Slides THOCN6 [5.266 MB]

THOCN7	Isochronous (CW) High Intensity Non-scaling FFAG Proton Drivers	focusing, acceleration, proton, simulation	2116
	C. Johnstone Fermilab, Batavia, USA M. Berz, K. Makino MSU, East Lansing, Michigan, USA S.R. Koscielniak TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada P. Snopok IIT, Chicago, Illinois, USA
	Funding: Work supported in part under SBIR grant DE-FG02-08ER85222 and by Fermi Research Alliance, under contract DEAC02-07CH11359, both with the U.S. Dept. of Energy The drive for higher beam power, duty cycle, and reliable beams at reasonable cost has focused world interest on fixed field accelerators, notably FFAGs. High-intensity GeV proton drivers encounter duty cycle and space-charge limits in the synchrotron and machine size concerns in cyclotrons. A 10^-20 MW proton driver is challenging, if even technically feasible, with conventional circular accelerators. Recently, the concept of isochronous orbits has been developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. Isochronous orbits enable the simplicity of fixed RF and, by tailoring the field profile, the FFAG can remain isochronous beyond the energy reach of cyclotrons. With isochronous orbits, the machine proposed here has the high average current advantage and duty cycle of the cyclotron in combination with the strong focusing, smaller losses that are more typical of the synchrotron. With the cyclotron as the current industrial and medical standard, a competing CW FFAG would impact facilities using medical accelerators, proton drivers for neutron production, and accelerator-driven nuclear reactors. This work reports on these new advances.
	Slides THOCN7 [2.429 MB]

THP005	High Power Cyclotron Complex for Neutron Production	proton, acceleration, electron, extraction	2145
	Yu.G. Alenitsky, A.A. Glazov, G.A. Karamysheva, S.A. Kostromin, E. Samsonov JINR, Dubna, Moscow Region, Russia S.N. Dolya, L.M. Onischenko, S.B. Vorozhtsov, N.L. Zaplatin JINR/DLNP, Dubna, Moscow region, Russia
	Now the cyclotron seems as the most suitable accelerator for production of proton beams with energy up to Ep= 800 MeV and the power Pp=10 MW. There are some offers on creation of such complexes, all of them have common properties. A full cycle of acceleration consists of three stages: high-voltage injection with bunching of continuous beam, then preliminary acceleration in fore sectors cyclotron and acceleration up to the maximal energy 500-800 MeV in the ring cyclotron with six or more sectors. At the first stage of acceleration instead of high-voltage injection one can use the parallel work of two cyclotrons with injection in the subsequent cascade of a beam of the double intensity. In our department of New Accelerators the magnetic and high-frequency systems of a ring cyclotron on the energy 50 - 800 MeV (so-called “supercyclotron”) have been developed. A project of cyclotron injector with energy of protons about 10 MeV has been suggested as injector for Fasotron JINR LNP. It is offered to continue development of the project of cyclotron facility with energy of protons Ер ~ 800 MeV and average current of beam up to 10 mA.

Paper

Title

Other Keywords

Page

MOOBN3

Comparison of Accelerator Technologies for use in ADSS

target, proton, linac, SRF

4

W.-T. Weng, H. Ludewig, D. Raparia, M. Todosow, D. Trbojevic
BNL, Upton, Long Island, New York, USA
P.M. McIntyre, A. Sattarov
Texas A&M University, College Station, Texas, USA

Funding: Work performed under the auspices of the US Department of Energy
Accelerator Driven Subcritical (ADS) fission is an interesting candidate basis for nuclear waste transmutation and for nuclear power generation. ADS can use either thorium or depleted uranium as fuel, operate below criticality, and consume rather than produce long-lived actinides. A case study with a hypothetical, but realistic nuclear core configuration is used to evaluate the performance requirements of the driver proton accelerator in terms of beam energy, beam current, duty factor, beam distribution delivered to the fission core, reliability, and capital and operating cost. Comparison between a CW IC and that of an SRF proton linac is evaluated. Future accelerator R&D required to improve each candidate accelerator design is discussed.

Slides MOOBN3 [1.540 MB]

MOP051

End-to-End Simulation of an Inverse Cyclotron for Muon Cooling

simulation, emittance, injection, collider

193

K. Paul, E. Cormier-Michel
Tech-X, Boulder, Colorado, USA
T. Hart, D.J. Summers
UMiss, University, Mississippi, USA

Funding: DOE Office of High-Energy Physics, SBIR DE-FG02-08ER85044
Neutrino factories and muon colliders require significant cooling of the muon beam. Most muon cooling channels are long and expensive single-pass structures, due to the difficulty injecting very large emittance beams into a circular device. Inverse cyclotrons can potentially solve the injection problems associated with other circular cooling channels, and they can potentially provide substantial initial cooling of the beam. We present the first end-to-end (injection to extraction) simulations of an inverse cyclotron for muon cooling, performed with the particle-in-cell code VORPAL. We study the cooling capability of the device as well as potential limitations due to space charge effects and material interactions with the beam.

MOP228

TE Wave Measurements of the Electron Cloud in a Dipole Magnetic Field

electron, resonance, plasma, dipole

531

S. De Santis, J.M. Byrd
LBNL, Berkeley, California, USA
J.R. Calvey, J. Joseph, J.A. Livezey, J.P. Sikora, K.G. Sonnad
CLASSE, Ithaca, New York, USA
K.C. Hammond
Harvard University, Cambridge, Massachusetts, USA

Funding: Work supported by the U.S. Department of Energy under Contract Nos. DE-AC02-05CH1123 and DE-FC02-08ER41538 and by the National Science Foundation Grant PHY-0734867.
The TE wave propagation method has become a widely used technique for measuring electron cloud density in an accelerator beampipe. In most instances the wave very low power is not capable of affecting the low-energy electrons distribution. During experiments in the CESR Damping Ring Test Accelerator (Cesr-TA), we have observed a particular situation where a resonance between the wave and a dipole magnetic field produces a large modification in the electron cloud distribution that can be measured by other detectors. We believe this resonance is strongly dependent on the geometry of standing waves pattern that discontinuities in the beampipe generate. We present measurements in Cesr-TA, which describe the effect and are in support of our hypothesis.

WEP190

Magnetic Field Expansion Out of a Plane: Application to Cyclotron Development

vacuum, simulation, focusing, factory

1846

T. Hart, D.J. Summers
UMiss, University, Mississippi, USA
K. Paul
Tech-X, Boulder, Colorado, USA

In studies of the dynamics of charged particles in a cyclotron magnetic field, the specified field is generally Bz in the z = 0 midplane where Br and Btheta are zero. Br(r,theta, z) and Btheta (r,theta, z) are usually determined through a linear expansion which assumes that Bz is independent of z. An expansion to only first order may not be sufficient for orbit simulations at small r and large z. This paper reviews the expansion of a specified Bz(r,theta, z = 0) out of the z = 0 midplane to arbitrary order, and shows simple examples worked out to 4th order.

WEP231

TRIUMF Cyclotron Beam Quality Improvement

extraction, TRIUMF, emittance, beam-losses

1921

I.V. Bylinskii, R.A. Baartman, F.W. Bach, J.F. Cessford, G. Dutto, Y.-N. Rao, L.W. Root, R. Ruegg
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

TRIUMF cyclotron for decades operated at 500 MeV. Recently, the two primary beamlines 1A and 2A, have been reconfigured for running at 480 MeV. The objective was to reduce beam losses caused by the electromagnetic stripping by 30%. The radiation losses reduction was confirmed with both online measurements and residual activation field mapping after 8 month of beam production. In order to improve stability of both primary beams, one of the harmonic coils was configured in Bz-mode to compensate for the beam split ratio fluctuations. Br-mode of this coil and two outer radius trim coils was utilized to correct the beam vertical position at extraction. Moreover, to make the beam spot position on the target stable and insensitive to any uncontrolled movement of the stripper foil due to heat distortion, the beamline front end optics was tuned to compensate the cyclotron's inherent dispersion. Details of these developments and improvements are discussed in the paper.

WEP232

A Multi Megawatt Ring Cyclotron to Search for CP Violation in the Neutrino Sector

extraction, injection, cavity, proton

1924

L. Calabretta, M.M. Maggiore, D. Rifuggiato
INFN/LNS, Catania, Italy
A. Calanna
CSFNSM, Catania, Italy
L.A.C. Piazza
INFN/LNL, Legnaro (PD), Italy

A new approach to search for CP violation in the neutrino sector* is proposed by the experiment called DAEδALUS (Decay At rest Experiment for cp At Laboratory for Underground Science). DAEδALUS needs three sources of neutrino fluxes, each one located at 1.5, 8 and 20 km from the underground detector. Each source has to be supplied with a proton beam with power higher than 1, 2 and 5 MW respectively. Here we present the study for a Superconducting Ring Cyclotron able to accelerate the H²⁺ molecules and to deliver proton beam with maximum energy of 800 MeV and the required power. Although the average power for the first 2 sites are 1 and 2 MW, the 20% duty cycle, required by the experiment, has the consequence that the peak power should stay in the range 5-10 MW and a peak current of about 4.5 mA of H²⁺ is necessary. We present the parameters of the superconducting magnetic sector simulated by the code TOSCA, the isochronous magnetic field produced and the magnetic forces acting on the coils. Some evaluation on the feasibility of the ring cyclotron, the advantages and problems relates with acceleration of the H²⁺ molecules will be also presented.
* J. Alonso et al., “Expression of Interest for a Novel Search for CP Violation in the Neutrino Sector: DAEδALUS”, Jun 2010. e-Print: arXiv:1006.0260

WEP237

The Oak Ridge Isochronous Cyclotron Refurbishment Project

extraction, ion, ISOL, vacuum

1930

A.J. Mendez, J.B. Ball, D. Dowling, S.W. Mosko, B.A. Tatum
ORNL, Oak Ridge, Tennessee, USA

Funding: Managed by UT-Battelle, LLC for the U.S. Department of Energy under contract DE-AC05-00OR22725.
The Oak Ridge Isochronous Cyclotron (ORIC) has been in operation for nearly fifty years at the Oak Ridge National Laboratory (ORNL). Presently, it serves as the driver accelerator for the ORNL Holifield Radioactive Ion Beam Facility (HRIBF), where beams are produced using the Isotope Separation Online (ISOL) technique for post-acceleration by the HRIBF 25URC tandem accelerator. Operability and reliability of ORIC are critical issues for the success of HRIBF and have presented increasingly difficult operational challenges for the facility in recent years. Earlier this year, a trim coil failure rendered ORIC inoperable for several months. This presented HRIBF with the opportunity to undertake various repairs and maintenance upgrades aimed at restoring the full functionality of ORIC and improving the reliability to a level better than what had been typical over the previous decade. In this paper, we present details of these efforts, including the replacement of the entire trim coil set and measurements of their radial field profile. Comparison of measurements and operating tune parameters with setup code predictions will also be presented.

THOCN6

Flux-coupled Cyclotron Stack: Optimization for Maximum Beam Power and Minimum Losses

cavity, coupling, injection, extraction

2113

P.M. McIntyre, A. Sattarov
Texas A&M University, College Station, Texas, USA

Funding: This work was supported in part by the U.S. Department of Energy under Grant DE-FG02-06ER41405
A flux-coupled stack of isochronous cyclotrons has been proposed as a driver for Accelerator-Driven Subcritical Systems (ADSS) for thorium-cycle fission power. The issues that limit beam current and phase space brightness are evaluated, including space charge tune shift, synchro-betatron coupling, orbit separation at injection and extraction, RF propagation within the accelerator envelope, RF parasitic modes, and stability of electrostatic septum operation. A design is presented that offers good optimization of these criteria.

Slides THOCN6 [5.266 MB]

THOCN7

Isochronous (CW) High Intensity Non-scaling FFAG Proton Drivers

focusing, acceleration, proton, simulation

2116

C. Johnstone
Fermilab, Batavia, USA
M. Berz, K. Makino
MSU, East Lansing, Michigan, USA
S.R. Koscielniak
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
P. Snopok
IIT, Chicago, Illinois, USA

Funding: Work supported in part under SBIR grant DE-FG02-08ER85222 and by Fermi Research Alliance, under contract DEAC02-07CH11359, both with the U.S. Dept. of Energy
The drive for higher beam power, duty cycle, and reliable beams at reasonable cost has focused world interest on fixed field accelerators, notably FFAGs. High-intensity GeV proton drivers encounter duty cycle and space-charge limits in the synchrotron and machine size concerns in cyclotrons. A 10^-20 MW proton driver is challenging, if even technically feasible, with conventional circular accelerators. Recently, the concept of isochronous orbits has been developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. Isochronous orbits enable the simplicity of fixed RF and, by tailoring the field profile, the FFAG can remain isochronous beyond the energy reach of cyclotrons. With isochronous orbits, the machine proposed here has the high average current advantage and duty cycle of the cyclotron in combination with the strong focusing, smaller losses that are more typical of the synchrotron. With the cyclotron as the current industrial and medical standard, a competing CW FFAG would impact facilities using medical accelerators, proton drivers for neutron production, and accelerator-driven nuclear reactors. This work reports on these new advances.

Slides THOCN7 [2.429 MB]

THP005

High Power Cyclotron Complex for Neutron Production

proton, acceleration, electron, extraction

2145

Yu.G. Alenitsky, A.A. Glazov, G.A. Karamysheva, S.A. Kostromin, E. Samsonov
JINR, Dubna, Moscow Region, Russia
S.N. Dolya, L.M. Onischenko, S.B. Vorozhtsov, N.L. Zaplatin
JINR/DLNP, Dubna, Moscow region, Russia

Now the cyclotron seems as the most suitable accelerator for production of proton beams with energy up to Ep= 800 MeV and the power Pp=10 MW. There are some offers on creation of such complexes, all of them have common properties. A full cycle of acceleration consists of three stages: high-voltage injection with bunching of continuous beam, then preliminary acceleration in fore sectors cyclotron and acceleration up to the maximal energy 500-800 MeV in the ring cyclotron with six or more sectors. At the first stage of acceleration instead of high-voltage injection one can use the parallel work of two cyclotrons with injection in the subsequent cascade of a beam of the double intensity. In our department of New Accelerators the magnetic and high-frequency systems of a ring cyclotron on the energy 50 - 800 MeV (so-called “supercyclotron”) have been developed. A project of cyclotron injector with energy of protons about 10 MeV has been suggested as injector for Fasotron JINR LNP. It is offered to continue development of the project of cyclotron facility with energy of protons Ер ~ 800 MeV and average current of beam up to 10 mA.