IPAC2012 - List of Authors (Zwaska, R.M.)

Paper	Title	Page
MOPPC019	Secondary Electron Yield Measurements of Fermilab’s Main Injector Vacuum Vessel	166
	D.J. Scott, D. Capista, K.L. Duel, R.M. Zwaska Fermilab, Batavia, USA S. Greenwald, W. Hartung, Y. Li, T.P. Moore, M.A. Palmer CLASSE, Ithaca, New York, USA R.E. Kirby, M.T.F. Pivi, L. Wang SLAC, Menlo Park, California, USA
	We discuss the progress made on a new installation in Fermilab’s Main Injector that will help investigate the electron cloud phenomenon by making direct measurements of the secondary electron yield (SEY) of samples irradiated in the accelerator. In the Project X upgrade the Main Injector will have its beam intensity increased by a factor of three compared to current operations. This may result in the beam being subject to instabilities from the electron cloud. Measured SEY values can be used to further constrain simulations and aid our extrapolation to Project X intensities. The SEY test-stand, developed in conjunction with Cornell and SLAC, is capable of measuring the SEY from samples using an incident electron beam when the samples are biased at different voltages. We present the design and manufacture of the test-stand and the results of initial laboratory tests on samples prior to installation.

MOPPD041	Beam Loss Protection for a 2.3 Megawatt LBNE Proton Beam	454
	R.M. Zwaska, S.C. Childress, A.I. Drozhdin, N.V. Mokhov, I.S. Tropin Fermilab, Batavia, USA
	Funding: U.S. Department of Energy. Severe limits are required for allowable beam loss during extraction and transport of a 2.3 MW primary proton beam for the Long Baseline Neutrino Experiment (LBNE) at Fermilab. Detailed simulations with the STRUCT and MARS codes have evaluated the impact of beam loss of 1.6·10¹⁴ protons per pulse at 120 GeV, ranging from a single pulse full loss to sustained small fractional loss. It is shown that localized loss of a single beam pulse at 2.3 MW will result in a destructive event: beam pipe failure, damaged magnets and high levels of residual radiation inside the tunnel. A sustained full beam loss would be catastrophic. Acceptable beam loss limits have been determined and robust solutions developed to enable efficient proton beam operation under these constraints.

WEPPR005	Study of Electron Cloud Instability in Fermilab Main Injector	2943
	K. Ohmi KEK, Ibaraki, Japan R.M. Zwaska Fermilab, Batavia, USA
	Electron cloud has been observed in Fermilab main injector. Electron signal is enhanced near the transition. The slippage factor which suppress instabilities approach to zero at the transition. Instabilities must be most serious near the transition. The instability caused by the electron cloud is an important issue for high intensity operation and the future toward Project-X. Simulations of electron cloud instability near the transition is presented.

Paper

Title

Page

Secondary Electron Yield Measurements of Fermilab’s Main Injector Vacuum Vessel

166

D.J. Scott, D. Capista, K.L. Duel, R.M. Zwaska
Fermilab, Batavia, USA
S. Greenwald, W. Hartung, Y. Li, T.P. Moore, M.A. Palmer
CLASSE, Ithaca, New York, USA
R.E. Kirby, M.T.F. Pivi, L. Wang
SLAC, Menlo Park, California, USA

We discuss the progress made on a new installation in Fermilab’s Main Injector that will help investigate the electron cloud phenomenon by making direct measurements of the secondary electron yield (SEY) of samples irradiated in the accelerator. In the Project X upgrade the Main Injector will have its beam intensity increased by a factor of three compared to current operations. This may result in the beam being subject to instabilities from the electron cloud. Measured SEY values can be used to further constrain simulations and aid our extrapolation to Project X intensities. The SEY test-stand, developed in conjunction with Cornell and SLAC, is capable of measuring the SEY from samples using an incident electron beam when the samples are biased at different voltages. We present the design and manufacture of the test-stand and the results of initial laboratory tests on samples prior to installation.

MOPPD041

Beam Loss Protection for a 2.3 Megawatt LBNE Proton Beam

454

R.M. Zwaska, S.C. Childress, A.I. Drozhdin, N.V. Mokhov, I.S. Tropin
Fermilab, Batavia, USA

Funding: U.S. Department of Energy.
Severe limits are required for allowable beam loss during extraction and transport of a 2.3 MW primary proton beam for the Long Baseline Neutrino Experiment (LBNE) at Fermilab. Detailed simulations with the STRUCT and MARS codes have evaluated the impact of beam loss of 1.6·10¹⁴ protons per pulse at 120 GeV, ranging from a single pulse full loss to sustained small fractional loss. It is shown that localized loss of a single beam pulse at 2.3 MW will result in a destructive event: beam pipe failure, damaged magnets and high levels of residual radiation inside the tunnel. A sustained full beam loss would be catastrophic. Acceptable beam loss limits have been determined and robust solutions developed to enable efficient proton beam operation under these constraints.

WEPPR005

Study of Electron Cloud Instability in Fermilab Main Injector

2943

K. Ohmi
KEK, Ibaraki, Japan
R.M. Zwaska
Fermilab, Batavia, USA

Electron cloud has been observed in Fermilab main injector. Electron signal is enhanced near the transition. The slippage factor which suppress instabilities approach to zero at the transition. Instabilities must be most serious near the transition. The instability caused by the electron cloud is an important issue for high intensity operation and the future toward Project-X. Simulations of electron cloud instability near the transition is presented.