2011 Particle Accelerator Conference - List of Authors (Tan, Y.)

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.

TUP253	AGS Tune Jump Power Supply Design and Test	1298
	J.-L. Mi, J.W. Glenn, H. Huang, I. Marneris, P.J. Rosas, J. Sandberg, Y. Tan, 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. A horizontal tune jump system has been installed to overcome the horizontal intrinsic spin resonances, which requires jumping the horizontal tune 0.04 units 82 times, 41 up and 41 down. Two quadruple magnets have been installed in AGS ring to do this. The pulsed magnet currents range from about 140 amps near injection to about 1400 amps late. Current pulse rise and fall times are around 100 micro-sec and flat tops time are around 4mS. These quadruples have separate supplies. This tune jump pulse power supply employees all semiconductor parts as the main switches. During dummy load and magnet testing, the test result showed that the power supply could meet the specification. This article will describe some detail of power supply simulation, design and testing. Some test waveform and pictures are presented in this paper.

TUP254	Real Time Monitoring of the Power Limit Resistor in the Boost Injection Kicker Power Supply	1301
	J.-L. Mi, J. Sandberg, Y. Tan, 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. After years of suffering Booster Injection Kicker transistor bank driver regulator trouble shooting, a new real time monitor system has been developed. A simple and floating circuit has been designed and tested. This circuit monitor system can real time monitor the driver regulator power limit resistor status and warn machine operators if the power limit resistor changes values. This paper will introduce the power supply mainly and the new designed monitoring system.

THP108	Analysis of RHIC Beam Dump Pre-fires	2327
	W. Zhang, L. A. Ahrens, W. Fischer, H. Hahn, J.-L. Mi, J. Sandberg, Y. Tan 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. It has been speculated that the beam may cause instability of the RHIC Beam Abort Kickers. In this study, we explore the available data of past beam operations, the device history of key modulator components, and the radiation patterns to examine the correlations.

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.

TUP253

AGS Tune Jump Power Supply Design and Test

1298

J.-L. Mi, J.W. Glenn, H. Huang, I. Marneris, P.J. Rosas, J. Sandberg, Y. Tan, 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.
A horizontal tune jump system has been installed to overcome the horizontal intrinsic spin resonances, which requires jumping the horizontal tune 0.04 units 82 times, 41 up and 41 down. Two quadruple magnets have been installed in AGS ring to do this. The pulsed magnet currents range from about 140 amps near injection to about 1400 amps late. Current pulse rise and fall times are around 100 micro-sec and flat tops time are around 4mS. These quadruples have separate supplies. This tune jump pulse power supply employees all semiconductor parts as the main switches. During dummy load and magnet testing, the test result showed that the power supply could meet the specification. This article will describe some detail of power supply simulation, design and testing. Some test waveform and pictures are presented in this paper.

TUP254

Real Time Monitoring of the Power Limit Resistor in the Boost Injection Kicker Power Supply

1301

J.-L. Mi, J. Sandberg, Y. Tan, 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.
After years of suffering Booster Injection Kicker transistor bank driver regulator trouble shooting, a new real time monitor system has been developed. A simple and floating circuit has been designed and tested. This circuit monitor system can real time monitor the driver regulator power limit resistor status and warn machine operators if the power limit resistor changes values. This paper will introduce the power supply mainly and the new designed monitoring system.

THP108

Analysis of RHIC Beam Dump Pre-fires

2327

W. Zhang, L. A. Ahrens, W. Fischer, H. Hahn, J.-L. Mi, J. Sandberg, Y. Tan
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.
It has been speculated that the beam may cause instability of the RHIC Beam Abort Kickers. In this study, we explore the available data of past beam operations, the device history of key modulator components, and the radiation patterns to examine the correlations.

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.