The Theory of Charged Particle Energy Loss and Multiple - MICE的带电粒子的能量损失和小鼠多理论.ppt

27 Oct 2004 Report for MICE meeting The Theory of Charged Particle Energy Loss and Multiple Scattering in Materials and its Application to Muons in Liquid Molecular Hydrogen,ELMS ? A brief summary and a report on work on its implication for Ionisation Cooling Wade Allison and Simon Holmes, Oxford Presented at MICE meeting at RAL 29th October 2004 Three stages Single collision level. Cross section for collision with given energy AND transverse momentum transfer as a function of incident momentum in liquid Hydrogen. DONE. Thence - 2. Thin sample level. Thin = 1mm (or β2 mm for non relativistic particles), such that cross section and path length constant within a sample. Generate probability maps by folding collision energy and momentum transfer probability in thinner layers.A complete database of 138 maps, 1mm or less, incident momentum from 5MeV/c to 50 GeV/c, 53 megabytes. DONE. Thence - 3. Tracking Using the above database with interpolation, a fast MC tracker with mm steps or less 103ms-1. Now working in ICOOL. Work in progress 1. The double differential cross section Need data input for atomic and molecular hydrogen Nuclear constituent coulomb scattering Overview Study of the contribution of different mechanisms 105 incident muons Momentum 200MeV/c Thickness 10cm Linear plot of projected transverse momentum transfer, MeV/c 105 incident muons Momentum 200MeV/c Thickness 10cm Linear plot of energy transfer, MeV Correlations between energy loss and scattering The story so far… Collisions with constituent electrons give rise to both energy loss and scattering ?correlation. Need to look at more complex geometries e.g. MICE Inserting ELMS into ICOOL v2.68 If Material = Liquid Hydrogen Bypass original Mstep routines by call to ‘ELMS’ Not including spin polarisation, yet Rest of simulation process unaffected Comparison - Distributions Correlation Suppression Done carefully we can make ELMS run uncorrelated.. Method: Pick two points on the three dimension