Considerations on Beam Diagnostics Physics Jilei Sun, Jingyu Tang (IHEP) International Review Meeting on C-ADS Accelerator Physics Design September 19, 2011

Outline Introduction Consideration of major diagnostic devices Beam diagnostics scheme for the first phase Summary

Introduction Beam current 10mA Frequency 325MHz Duty factor 100% Energy up to 1.5GeV 3.08 ns (325MHz) Current 10mA

Aim Commission the accelerator Monitor and maintain normal operation Protect the hardware Provide information for trouble-shooting Types On-line Characterization

Interesting properties Energy Intensity Beam profile Position Emittance Beam loss

Scheme of the C-ADS beam diagnostic systems

Consideration of major diagnostic devices Beam Position Monitors (BPM) Steer and center the beam in the aperture Warm BPM (strip-line) and cold BPM (considered to be button type)

Beam Current Transformers (BCT) Provide the transmission efficiency in the initial commissioning Monitor the variation of beam current during the operation

Beam loss monitors (BLM) Minimize the beam losses Significant part in the MPS Beam profile monitors (Wire Scanner) Measures the emittance and envelopes WS used in the commissioning with reduced beam power Non-interceptive type

Beam phase monitors BPM or Fast BCT (FCT) Emittance measurement Double-slit system in LEBT &MEBT Multi-profile method for high energy Collimators LEBT, MEBT1 and MEBT2

Diagnostics-box Modest power beam stop. Double-slit emittance measurement system.

Existing devices

Beam diagnostics scheme for the first phase At the moment, only the injector diagnostics has been designed. For the MEBT1-1

Parameters of the diagnostic devices for the MEBT1 Quantity z-extent(mm) Measures Accuracy Response Beam Position Monitors (BPM) 6 <90 Position/ Phase <±0.1mm —— Fast Current Transformer (FCT) 2 <50 current <0.1mA <50ns Beam Loss Monitors (BLM) 3 beam loss <1% <2us Wire Scanner（WS） <60 x/y profile <0.1mm Emittance 1 Transverse emittance <2% Beam stop

For the 3~5MeV Cold BPM (considered to be button type). D-box with beam stop and double-slit emittance measurement system.

Summary BPM, BLM, FCT, BLM, D-box…will be used in the C-ADS diagnostic systems. Some prototypes are exist in IHEP. The scheme of the diagnostic system for the first phase has been finished.

Thanks for your attention!