Author: McCrady, R.C.
Paper Title Page
TUPPC049 A Tapered-foil Emittance-exchange Experiment at LANSCE 1278
 
  • R.C. McCrady
    LANL, Los Alamos, New Mexico, USA
 
  We are planning an experiment at the Los Alamos Neutron Science Center (LANSCE) to demonstrate a technique for reducing the transverse emittance of the proton beam by passing the beam through a wedge-shaped energy degrader to produce a non-symplectic correlation between transverse position and energy, then removing this correlation with a bending magnet. This technique was proposed by Peterson* in 1983. We present a specific beamline layout that is expected to mitigate several complications associated with fielding an experiment to demonstrate the technique with a low-emittance proton beam. We present simulated results and expected outcomes of this demonstration.
* J. M. Peterson, Proc. of PAC 1983, pP. 2403-2405 (1984).
 
 
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.