2011 Particle Accelerator Conference - List of Authors (Okamura, M.)

Paper	Title	Page
MOP209	Proposed Scattered Electron Detector System as One of the Beam Overlap Diagnostic Tools for the New RHIC Electron Lens	489
	P. Thieberger, E.N. Beebe, C. Chasman, W. Fischer, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, R.F. Lambiase, Y. Luo, M.G. Minty, C. Montag, M. Okamura, A.I. Pikin, Y. Tan, J.E. Tuozzolo, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. An electron lens for head-on beam-beam compensation planned for RHIC requires precise overlap of the electron and proton beams which both can have down to 0.3 mm rms transverse radial widths along the 2m long interaction region. Here we describe a new diagnostic tool that is being considered to aid in the tuning and verification of this overlap. Some of ultra relativistic protons (100 or 250 GeV) colliding with low energy electrons (2 to 10 keV) will transfer sufficient transverse momentum to cause the electrons to spiral around the magnetic guiding field in a way that will make them detectable outside of the main solenoid. Time-of-flight of the halo electron signals will provide position-sensitive information along the overlap region. Scattering cross sections are calculated and counting rate estimates are presented as function of electron energy and detector position.

TUP207	The Effects of the RHIC E-lenses Magnetic Structure Layout on the Proton Beam Trajectory	1202
	X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed in RHIC IR10. First, the layout of these two E-lenses is introduced. Then the effects of e-lenses on proton beam are discussed. For example, the transverse fields of the e-lens bending solenoids and the fringe field of the main solenoids will shift the proton beam. For the effects of the e-lens on proton beam trajectory, we calculate the transverse kicks that the proton beam receives in the electron lens via Opera at first. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.

TUP208	DESIGNING A BEAM TRANSPORT SYSTEM FOR RHIC’S ELECTRON LENS	1205
	X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. We designed two electron lenses to apply head-on beam-beam compensation for RHIC; they will be installed near IP10. The electron-beam transport system is an important subsystem of the entire electron-lens system. Electrons are transported from the electron gun to the main solenoid and further to the collector. The system must allow for changes of the electron beam size inside the superconducting magnet, and for changes of the electron position by 5 mm in the horizontal- and vertical-planes.

WEP264	Laser Ion Source With Long Pulse Width for RHIC-EBIS	1972
	K. Kondo, M. Okamura BNL, Upton, Long Island, New York, USA T. Kanesue Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka, Japan
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy and by the National Aeronautics and Space Administration. The Electron Beam Ion Source (EBIS) at Brookhaven National Laboratory is a new heavy ion-projector for RHIC and NASA Space Radiation Laboratory. Laser Ion Source (LIS) with solenoid can supply many kinds of ion from solid targets and is suitable for long pulse length with low current as ion provider for RHIC-EBIS. In order to understand a plasma behavior for fringe field of solenoid, we measure current, pulse width and total ion charges by a new ion probe. The experimental result indicates that the solenoid confines the laser ablation plasma transversely.

WEP268	Changes in LEBT/MEBT at the BNL 200 MeV Linac	1978
	D. Raparia, J.G. Alessi, J.M. Fite, O. Gould, V. LoDestro, M. Okamura, J. Ritter, A. Zelenski BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. After reconfiguration of the low energy (35 keV) and the medium energy (750 keV) transport lines in 2009-10, the Brookhaven linac is now delivering the highest intensity beam since it was built in 1970 (~120 μA average current of H⁻ to the Brookhaven Linac Isotope Producer). It is also now delivering lower emittance polarized H⁻ ion beam for the polarized program at RHIC. To increase the intensity further, we are replacing the buncher in the 750 keV line with one with higher Q value, to allow operation at higher power. Also, to improve polarization, we are replacing the magnetic solenoid before the RFQ in the 35 keV line by a solenoid-einzel lens combination. The paper will report on the results of these changes.

THP044	Linear Accelerator Design Study with Direct Plasma Injection Scheme for Warm Dense Matter	2199
	K. Kondo, M. Okamura BNL, Upton, Long Island, New York, USA T. Kanesue Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka, Japan
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Warm Dense Matter (WDM) is a growing rapidly science field, which is related to planetary science and inertial fusion. It is difficult to expect the behavior because the state with high density and low temperature is completely different from ideal condition. The well-defined WDM generation is required to understand it. Moderate energy ion beam (~ 0.3 MeV/u) slightly above Bragg peak is an advantageous method for WDM because of the uniform energy deposition. Direct Plasma Injection Scheme (DPIS) with a linear accelerator has a potential for the beam parameter. The design of linear accelerator for WDM is presented.

WEP261	Performance of the New EBIS Preinjector	1966
	J.G. Alessi, E.N. Beebe, S. Binello, C.J. Gardner, O. Gould, L.T. Hoff, N.A. Kling, R.F. Lambiase, V. LoDestro, R. Lockey, M. Mapes, A. McNerney, J. Morris, M. Okamura, A. Pendzick, D. Phillips, A.I. Pikin, D. Raparia, J. Ritter, T.C. Shrey, L. Smart, L. Snydstrup, C. Theisen, M. Wilinski, A. Zaltsman, K. Zeno BNL, Upton, Long Island, New York, USA U. Ratzinger, A. Schempp IAP, Frankfurt am Main, Germany
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy, and by the National Aeronautics and Space Administration. The construction and initial commissioning phase of a new heavy ion preinjector was completed at Brookhaven in September, 2010, and the preinjector is now operational. This preinjector, using an EBIS source to produce high charge state heavy ions, provided helium and neon ion beams for use at the NASA Space Radiation Laboratory in the Fall of 2010, and gold and uranium beams are being commissioned during the 2011 run cycle for use in RHIC. The EBIS operates with an electron beam current of up to 10 A, to produce mA level currents in 10 to 40 μs beam pulses. The source is followed by an RFQ and IH linac to accelerate ions with q/m > 0.16 to an energy of 2 MeV/amu, for injection into the Booster synchrotron. The performance of the preinjector is presented, including initial operational experience for the NASA and RHIC programs.

THP055	Status of the RHIC Head-on Beam-beam Compensation Project	2223
	W. Fischer, M. Anerella, E.N. Beebe, D. Bruno, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, A.K. Jain, R.F. Lambiase, C. Liu, Y. Luo, M. Mapes, T.A. Miller, C. Montag, B. Oerter, M. Okamura, A.I. Pikin, D. Raparia, Y. Tan, R. Than, P. Thieberger, J.E. Tuozzolo, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy. Two electron lenses are under construction for RHIC to partially compensate the head-on beam-beam effect in order to increase both the peak and average luminosity. The final design of the overall system is reported as well as the status of the component design, acquisition, and manufacturing.

THP100	Structure and Design of the Electron Lens for RHIC	2309
	A.I. Pikin, J.G. Alessi, M. Anerella, E.N. Beebe, W. Fischer, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, R.F. Lambiase, Y. Luo, C. Montag, M. Okamura, Y. Tan, P. Thieberger, J.E. Tuozzolo, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Two electron lenses for a head-on beam-beam compensation are being planned for RHIC; one for each circulating proton beam. The transverse profile of the electron beam will be Gaussian up to a maximum radius of re=3σ. Simulations and design of the electron gun with Gaussian radial emission current density profile and of the electron collector are presented. Ions of the residual gas generated in the interaction region by electron and proton beams will be removed by an axial gradient of the electric field towards the electron collector. A method of optical observation the transverse profile of the electron beam is described.

Paper

Title

Page

Proposed Scattered Electron Detector System as One of the Beam Overlap Diagnostic Tools for the New RHIC Electron Lens

489

P. Thieberger, E.N. Beebe, C. Chasman, W. Fischer, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, R.F. Lambiase, Y. Luo, M.G. Minty, C. Montag, M. Okamura, A.I. Pikin, Y. Tan, J.E. Tuozzolo, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
An electron lens for head-on beam-beam compensation planned for RHIC requires precise overlap of the electron and proton beams which both can have down to 0.3 mm rms transverse radial widths along the 2m long interaction region. Here we describe a new diagnostic tool that is being considered to aid in the tuning and verification of this overlap. Some of ultra relativistic protons (100 or 250 GeV) colliding with low energy electrons (2 to 10 keV) will transfer sufficient transverse momentum to cause the electrons to spiral around the magnetic guiding field in a way that will make them detectable outside of the main solenoid. Time-of-flight of the halo electron signals will provide position-sensitive information along the overlap region. Scattering cross sections are calculated and counting rate estimates are presented as function of electron energy and detector position.

TUP207

The Effects of the RHIC E-lenses Magnetic Structure Layout on the Proton Beam Trajectory

1202

X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We are designing two electron lenses (E-lens) to compensate for the large beam-beam tune spread from proton-proton interactions at IP6 and IP8 in the Relativistic Heavy Ion Collider (RHIC). They will be installed in RHIC IR10. First, the layout of these two E-lenses is introduced. Then the effects of e-lenses on proton beam are discussed. For example, the transverse fields of the e-lens bending solenoids and the fringe field of the main solenoids will shift the proton beam. For the effects of the e-lens on proton beam trajectory, we calculate the transverse kicks that the proton beam receives in the electron lens via Opera at first. Then, after incorporating the simplified E-lens lattice in the RHIC lattice, we obtain the closed orbit effect with the Simtrack Code.

TUP208

DESIGNING A BEAM TRANSPORT SYSTEM FOR RHIC’S ELECTRON LENS

1205

X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We designed two electron lenses to apply head-on beam-beam compensation for RHIC; they will be installed near IP10. The electron-beam transport system is an important subsystem of the entire electron-lens system. Electrons are transported from the electron gun to the main solenoid and further to the collector. The system must allow for changes of the electron beam size inside the superconducting magnet, and for changes of the electron position by 5 mm in the horizontal- and vertical-planes.

WEP264

Laser Ion Source With Long Pulse Width for RHIC-EBIS

1972

K. Kondo, M. Okamura
BNL, Upton, Long Island, New York, USA
T. Kanesue
Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka, Japan

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy and by the National Aeronautics and Space Administration.
The Electron Beam Ion Source (EBIS) at Brookhaven National Laboratory is a new heavy ion-projector for RHIC and NASA Space Radiation Laboratory. Laser Ion Source (LIS) with solenoid can supply many kinds of ion from solid targets and is suitable for long pulse length with low current as ion provider for RHIC-EBIS. In order to understand a plasma behavior for fringe field of solenoid, we measure current, pulse width and total ion charges by a new ion probe. The experimental result indicates that the solenoid confines the laser ablation plasma transversely.

WEP268

Changes in LEBT/MEBT at the BNL 200 MeV Linac

1978

D. Raparia, J.G. Alessi, J.M. Fite, O. Gould, V. LoDestro, M. Okamura, J. Ritter, A. Zelenski
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
After reconfiguration of the low energy (35 keV) and the medium energy (750 keV) transport lines in 2009-10, the Brookhaven linac is now delivering the highest intensity beam since it was built in 1970 (~120 μA average current of H⁻ to the Brookhaven Linac Isotope Producer). It is also now delivering lower emittance polarized H⁻ ion beam for the polarized program at RHIC. To increase the intensity further, we are replacing the buncher in the 750 keV line with one with higher Q value, to allow operation at higher power. Also, to improve polarization, we are replacing the magnetic solenoid before the RFQ in the 35 keV line by a solenoid-einzel lens combination. The paper will report on the results of these changes.

THP044

Linear Accelerator Design Study with Direct Plasma Injection Scheme for Warm Dense Matter

2199

K. Kondo, M. Okamura
BNL, Upton, Long Island, New York, USA
T. Kanesue
Kyushu University, Department of Applied Quantum Physics and Nuclear Engineering, Fukuoka, Japan

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Warm Dense Matter (WDM) is a growing rapidly science field, which is related to planetary science and inertial fusion. It is difficult to expect the behavior because the state with high density and low temperature is completely different from ideal condition. The well-defined WDM generation is required to understand it. Moderate energy ion beam (~ 0.3 MeV/u) slightly above Bragg peak is an advantageous method for WDM because of the uniform energy deposition. Direct Plasma Injection Scheme (DPIS) with a linear accelerator has a potential for the beam parameter. The design of linear accelerator for WDM is presented.

WEP261

Performance of the New EBIS Preinjector

1966

J.G. Alessi, E.N. Beebe, S. Binello, C.J. Gardner, O. Gould, L.T. Hoff, N.A. Kling, R.F. Lambiase, V. LoDestro, R. Lockey, M. Mapes, A. McNerney, J. Morris, M. Okamura, A. Pendzick, D. Phillips, A.I. Pikin, D. Raparia, J. Ritter, T.C. Shrey, L. Smart, L. Snydstrup, C. Theisen, M. Wilinski, A. Zaltsman, K. Zeno
BNL, Upton, Long Island, New York, USA
U. Ratzinger, A. Schempp
IAP, Frankfurt am Main, Germany

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy, and by the National Aeronautics and Space Administration.
The construction and initial commissioning phase of a new heavy ion preinjector was completed at Brookhaven in September, 2010, and the preinjector is now operational. This preinjector, using an EBIS source to produce high charge state heavy ions, provided helium and neon ion beams for use at the NASA Space Radiation Laboratory in the Fall of 2010, and gold and uranium beams are being commissioned during the 2011 run cycle for use in RHIC. The EBIS operates with an electron beam current of up to 10 A, to produce mA level currents in 10 to 40 μs beam pulses. The source is followed by an RFQ and IH linac to accelerate ions with q/m > 0.16 to an energy of 2 MeV/amu, for injection into the Booster synchrotron. The performance of the preinjector is presented, including initial operational experience for the NASA and RHIC programs.

THP055

Status of the RHIC Head-on Beam-beam Compensation Project

2223

W. Fischer, M. Anerella, E.N. Beebe, D. Bruno, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, A.K. Jain, R.F. Lambiase, C. Liu, Y. Luo, M. Mapes, T.A. Miller, C. Montag, B. Oerter, M. Okamura, A.I. Pikin, D. Raparia, Y. Tan, R. Than, P. Thieberger, J.E. Tuozzolo, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy.
Two electron lenses are under construction for RHIC to partially compensate the head-on beam-beam effect in order to increase both the peak and average luminosity. The final design of the overall system is reported as well as the status of the component design, acquisition, and manufacturing.

THP100

Structure and Design of the Electron Lens for RHIC

2309

A.I. Pikin, J.G. Alessi, M. Anerella, E.N. Beebe, W. Fischer, D.M. Gassner, X. Gu, R.C. Gupta, J. Hock, R.F. Lambiase, Y. Luo, C. Montag, M. Okamura, Y. Tan, P. Thieberger, J.E. Tuozzolo, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Two electron lenses for a head-on beam-beam compensation are being planned for RHIC; one for each circulating proton beam. The transverse profile of the electron beam will be Gaussian up to a maximum radius of re=3σ. Simulations and design of the electron gun with Gaussian radial emission current density profile and of the electron collector are presented. Ions of the residual gas generated in the interaction region by electron and proton beams will be removed by an axial gradient of the electric field towards the electron collector. A method of optical observation the transverse profile of the electron beam is described.