Title :
Fast reconstruction of beams in intense proton accelerators
Author :
Brandstätter, Bernhard
Author_Institution :
Inst. for Fundamentals & Theor. Electr. Eng., Graz, Austria
fDate :
3/1/2002 12:00:00 AM
Abstract :
Conventional methods of monitoring beam locations in a pipe involve measuring signals from strip lines or taking the image of a fluorescent screen inside the beam vacuum pipe. However, these methods, which are called invasive, cannot be applied to the intense proton accelerator dealing with 1.5 GeV. This paper introduces a fast noninvasive method of reconstructing the beam from measurements of the magnetic field, produced by the beam, outside the vacuum pipe. The proposed reconstruction method is based on a Gauss-Newton scheme in addition with a variance uniformization constraint (which will be derived in this paper) to overcome the ill-posed nature of the problem. With this method, the location of the beam within the beam pipe can be reconstructed with satisfying accuracy after just one Gauss-Newton step
Keywords :
Jacobian matrices; current distribution; image reconstruction; inverse problems; magnetic fields; particle beam diagnostics; proton accelerators; 1.5 GeV; Biot-Savart law; Gauss-Newton scheme; beam locations; fast beam profile reconstruction; fast noninvasive method; filamentary currents; intense proton accelerators; inverse problem; magnetic field measurements; vacuum pipe; variance uniformization constraint; Fluorescence; Image reconstruction; Least squares methods; Magnetic field measurement; Monitoring; Newton method; Particle beams; Proton accelerators; Recursive estimation; Strips;
Journal_Title :
Magnetics, IEEE Transactions on