Proposed Model for Build Up Simulations


round proton bunches in a round pipe
chamber radius 2 cm
20 bunches
bunch spacing 7.48 m
bunch population 1e11
rms bunch length 7.7 cm (Gaussian profile, truncated at +/- 2 sqrt(3) sigma_z)
rms transverse beam size 300 microns (Gaussian profile)
no magnetic field
primary electron rate: 1e-3 per proton per meter launched uniformly (in azimuth) on the chamber wall
 

true secondaries with delta_max=1.6, epsilon_max=250 eV


[OLD: fraction of elastically reflected electrons given by Noel Hilleret's lower-energy fit function f ]

NEW: probability of elastic reflection given by quantum-mechanical fit to Cimino-Collins data, with d(0)=1; detailed description of secondary emission model



result: electron line charge (total no. of e- per unit length) as a function of time


2002 simulations results from various codes for above model 

new 2004 simulations results from various codes for above model


2006 benchmarking of ECLOUD and POSINST for LHC dipole



Last updated 30 May 2004, FZ