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Collimation study for the ILC e+ source. Y. Nosochkov and F. Zhou. 03/14/07. PCAP lattice by Yuri-N 07/28/2006. 03/14/07. PPATEL. X (m). Y (m). PCAP. PPA. Z (m). PTRAN. 03/14/07. PTRAN. PPATEL. PPA. PCAP.
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Collimation study for the ILC e+ source Y. Nosochkov and F. Zhou 03/14/07
PCAP lattice by Yuri-N 07/28/2006 03/14/07
PPATEL X (m) Y (m) PCAP PPA Z (m) PTRAN 03/14/07
PTRAN PPATEL PPA PCAP • Yuri-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. W/ preliminary collimation 03/14/07
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 DR 03/14/07
Basic requirements for the e+ source collimation • Protect magnets and RF structures along the whole e+ source: power loss <100 W/m and no loss (<1 W/m) in CM booster sections. • Mitigate power loss in the collimator at LTR, which implies to collimate e+ (which are eventually not captured by DR) as much as possible at low energy: - Optimize -collimators at PCAP - No better way to collimate tails with wide-energy except rotating longitudinal phase space through energy compression. 03/14/07
Reconstructed phase space at PCAP exit Lost in PCAP Lost in PPA Lost in PPATEL Beyond DR acceptance Captured by DR 03/14/07
Update of collimation system • 5827 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 30 • Add 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
Mostly lost in collimators Particles loss with updated collimation 03/14/07
Power loss calculation • Power 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 collimation 03/14/07
Lost in PCAP Lost in PPA Lost in PPATEL Lost in PTRAN Beyond DR acceptance Captured by DR W/ preliminary collimation Lost in PCAP Lost in PPA Lost in PPATEL Lost in PTRAN Lost in LTR collimatorx Beyond 6-D O beyond 4-D Captured by DR W/ updated collimation 03/14/07
Lost in beamlines Captured by DRX Beyond 6-D O beyond 4-D X – X’ Y – Y’ 03/14/07
Summary • Collimation system is updated: - Power loss in individual magnet and drift <100 W/m - Power loss in LTR collimator: 49 kW (1 collimator) 22.5 kW and 26.5 kW (2 collimators) - Power loss in DR is 2.8 kW @ 3E10 • Optimizing -collimator (y-aperture) may help to reduce e+, which are not captured by DR, but it will sacrifice to lose e+, which are within DR acceptance. • With the full collimation system, 46% of target particles are captured in DR • Need to study energy deposition and activation in the LTR collimators • Need to check for the shielded target scheme 03/14/07