Collimation study for the ILC e+ sourceY. Nosochkov and F. Zhou03/14/07

PCAP lattice by Yuri-N 07/28/200603/14/07

PTRAN03/14/07

03/14/07W/ preliminary collimationYuri-N proposed preliminary collimation system in the PCAP; better control of loss in the PCAP magnets.To reduce power loss in the magnets downstream of the PCAP, we need to optimize existing collimators and add more collimators.

Reconstructed phase space at PCAP entrance (W/ preliminary collimation) Lost in PCAP Lost in PPA Lost in PPATEL Lost in PTRAN Beyond DR acceptance Captured by DR03/14/07

Basic requirements for the e+ source collimationProtect magnets and RF structures along the whole e+ source: power loss

Reconstructed phase space at PCAP exit03/14/07 Lost in PCAP Lost in PPA Lost in PPATEL Beyond DR acceptance Captured by DR

Update of collimation system5827 of e+ at target; 4614 at PCAP entrance Optimize existing collimators and add one -collimator in PCAP: - Reduce e+ loss in PPA from 167 to 20 - Reduce e+, which are eventually not captured by DR - Reduce e+ loss in PPATEL and PTRAN Add one energy collimator and another aperture collimator at PPATEL: - Reduce e+ loss in PPATEL magnets to 32 - Reduce e+ loss in PTRAN to 30Add one or two energy collimators at LTR - Reduce e+ loss to 24 at DR; 334 e+ lost in LTR collimator; totally 2677 e+ captured by DR (~46% of e+ at target) 03/14/07

03/14/07Particles loss with updated collimation

Power loss calculationPower loss in magnets along the beamline will be calculated soon. Power loss in LTR collimator (beam power 315 kW@ 3E10): 49 kW loss (1 collimator); 22.5 kW and 26.5 kW (2 collimators) Power loss in DR: 24 particles among 2701; 2.8 kW loss@3E10 in DR 46% particles of target particles are captured in DR after the collimation03/14/07

Lost in PCAP Lost in PPA Lost in PPATEL Lost in PTRAN Beyond DR acceptance Captured by DR Lost in PCAP Lost in PPA Lost in PPATEL Lost in PTRAN Lost in LTR collimator x Beyond 6-D O beyond 4-D Captured by DRW/ preliminary collimationW/ updated collimation03/14/07

Lost in beamlines Captured by DR X Beyond 6-D O beyond 4-D X XY Y03/14/07

SummaryCollimation system is updated: - Power loss in individual magnet and drift