IPAC2012 - List of Authors (Pang, X.)

Paper	Title	Page
MOEPPB012	High-performance Beam Simulator for the LANSCE Linac	103
	X. Pang, S.A. Baily, L. Rybarcyk LANL, Los Alamos, New Mexico, USA
	Funding: U.S. Dept. of Energy, NNSA under contract DE-AC52-06NA25396. The LANSCE accelerator complex is a multi-beam facility that provides high-intensity H⁺ and H⁻ particle beams for a variety of user programs. At the heart of the facility is a room temperature linac that is comprised of a 100-MeV drift tube linac and an 800-MeV coupled cavity linac. During beam operations, linac parameters are adjusted to maintain minimal beam spill, but without detailed knowledge of the beam distribution. A more desirable situation would be one where knowledge of the beam distribution along the linac is available to aid in the optimization of the linac operation and beam performance. We are presently developing a high performance simulator that will provide valuable information about the beam distribution in pseudo real-time during linac operations. The heart of the simulator is based upon the multiparticle beam dynamics code PARMILA, but implemented in C++ using NVIDIA’s CUDA technology for Graphics Processing unit (GPU) hardware. Linac operating set points will be provided by the EPICS control system so that changes are tracked and the simulation results updated automatically. Details regarding the approach, benefits and performance will be presented.

WEPPR038	Independent Component Analysis (ICA) Applied to Long Bunch Beams in the Los Alamos Proton Storage Ring	3018
	J.S. Kolski, R.J. Macek, R.C. McCrady, X. Pang LANL, Los Alamos, New Mexico, USA
	Independent component analysis (ICA) is a powerful blind source separation (BSS) method. Compared to the typical BSS method, principal component analysis (PCA), which is the BSS foundation of the well known model independent analysis (MIA), ICA is more robust to noise, coupling, and nonlinearity. ICA of turn-by-turn beam position data has been used to measure the transverse betatron phase and amplitude functions, dispersion function, linear coupling, sextupole strength, and nonlinear beam dynamics. We apply ICA in a new way to slices along the bunch and discuss the source signals identified as betatron motion and longitudinal beam structure.

THPPP067	H⁻ Beam Loss and Evidence for Intrabeam Stripping in the LANSCE Linac	3892
	L. Rybarcyk, C.T. Kelsey, R.C. McCrady, X. Pang LANL, Los Alamos, New Mexico, USA
	Funding: U.S. Dept. of Energy, NNSA, under contract DE-AC52-06NA25396. The LANSCE accelerator complex is a multi-beam, multi-user facility that provides high-intensity H⁺ and H⁻ particle beams for a variety of user programs. At the heart of the facility is a room temperature linac that is comprised of 100-MeV drift tube and 800-MeV coupled cavity linac (CCL) structures. Although both beams are similar in intensity and emittance, the beam-loss monitors along the CCL show a trend of increased loss for H⁻ that is not present for H⁺. This difference is attributed to stripping mechanisms that affect H⁻ and not H⁺. We present the results of an analysis of H⁻ beam loss along the CCL that incorporates beam spill measurements, beam dynamics simulations, analytical models and radiation transport estimates using the MCNPX code. The results indicate a significant fraction of these additional losses result from intrabeam stripping.

Paper

Title

Page

High-performance Beam Simulator for the LANSCE Linac

103

X. Pang, S.A. Baily, L. Rybarcyk
LANL, Los Alamos, New Mexico, USA

Funding: U.S. Dept. of Energy, NNSA under contract DE-AC52-06NA25396.
The LANSCE accelerator complex is a multi-beam facility that provides high-intensity H⁺ and H⁻ particle beams for a variety of user programs. At the heart of the facility is a room temperature linac that is comprised of a 100-MeV drift tube linac and an 800-MeV coupled cavity linac. During beam operations, linac parameters are adjusted to maintain minimal beam spill, but without detailed knowledge of the beam distribution. A more desirable situation would be one where knowledge of the beam distribution along the linac is available to aid in the optimization of the linac operation and beam performance. We are presently developing a high performance simulator that will provide valuable information about the beam distribution in pseudo real-time during linac operations. The heart of the simulator is based upon the multiparticle beam dynamics code PARMILA, but implemented in C++ using NVIDIA’s CUDA technology for Graphics Processing unit (GPU) hardware. Linac operating set points will be provided by the EPICS control system so that changes are tracked and the simulation results updated automatically. Details regarding the approach, benefits and performance will be presented.

WEPPR038

Independent Component Analysis (ICA) Applied to Long Bunch Beams in the Los Alamos Proton Storage Ring

3018

J.S. Kolski, R.J. Macek, R.C. McCrady, X. Pang
LANL, Los Alamos, New Mexico, USA

Independent component analysis (ICA) is a powerful blind source separation (BSS) method. Compared to the typical BSS method, principal component analysis (PCA), which is the BSS foundation of the well known model independent analysis (MIA), ICA is more robust to noise, coupling, and nonlinearity. ICA of turn-by-turn beam position data has been used to measure the transverse betatron phase and amplitude functions, dispersion function, linear coupling, sextupole strength, and nonlinear beam dynamics. We apply ICA in a new way to slices along the bunch and discuss the source signals identified as betatron motion and longitudinal beam structure.

THPPP067

H⁻ Beam Loss and Evidence for Intrabeam Stripping in the LANSCE Linac

3892

L. Rybarcyk, C.T. Kelsey, R.C. McCrady, X. Pang
LANL, Los Alamos, New Mexico, USA

Funding: U.S. Dept. of Energy, NNSA, under contract DE-AC52-06NA25396.
The LANSCE accelerator complex is a multi-beam, multi-user facility that provides high-intensity H⁺ and H⁻ particle beams for a variety of user programs. At the heart of the facility is a room temperature linac that is comprised of 100-MeV drift tube and 800-MeV coupled cavity linac (CCL) structures. Although both beams are similar in intensity and emittance, the beam-loss monitors along the CCL show a trend of increased loss for H⁻ that is not present for H⁺. This difference is attributed to stripping mechanisms that affect H⁻ and not H⁺. We present the results of an analysis of H⁻ beam loss along the CCL that incorporates beam spill measurements, beam dynamics simulations, analytical models and radiation transport estimates using the MCNPX code. The results indicate a significant fraction of these additional losses result from intrabeam stripping.