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EMMA WCM-Based Bunch Charge Monitoring Set-up. A. Kalinin EMMA tasks, experiments, and procedures 01 March 2012. Existing set-up:. IL BPM1 Cable to MCR BPM Scope Combiner Ring/Ext BPM Front-Ends A pair of vertical buttons is used.
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EMMA WCM-Based Bunch Charge Monitoring Set-up A. Kalinin EMMA tasks, experiments, and procedures 01 March 2012
Existing set-up: IL BPM1 Cable to MCR BPM Scope Combiner Ring/Ext BPM Front-Ends A pair of verticalbuttons is used. The Front-Ends are modifiedto sum up two button signals. To see bunch charge in the ALICE train (+FC), the first bunch in particular. To compare the EMMA bunch charge to the ALICE bunch charge. To have a turn-by-turn charge picture not obscured by bunch oscillation. To see a charge at the extraction.
A new WCM-based set-up: IL WCM Splitter 6dB to EMMA ToF Scope, Trigger Cable, ~17m Ring WCM Splitter 6dB to EMMA ToF Scope, ToF? Combiner 6dB Front-End Coupler Cable, ~9m Att 1dB EL WCM Cable, ~1m Att (6+2)dB Cable to MCR MCR BPM Scope
Bunch charge signals: ... IL first turn second turn n-th turn EL ~15ns 55.2ns ~18ns Use of the Ring WCM for ToF • WCM bandwidth is ~4.5GHz, the output is a bell-shape pulse ~100ps. The magnitude is ~(40pC/100ps)x2Ohm=0.8V. • Irregular couplers are available to transform to the ‘derivative’ shape. Transformation ~1/10. Coupler 1, the slope always ~700ps Coupler 2, slope = pulse length For 20MS/s, 14 samples 3 samples