1. LHC BI 2015 Summary: BSRL M. Palm (BE-BI-PM) 2015-11-12 1

2. Changes since Run 1 Optical line BSRL and BSRA on extension table Hybrid detectors installed Both beams since TS2 TS3 Hybrid shutter control installed Additional layer of protection against saturation 2015-11-12 2 APD Synchrotron light BSRA Hybrid

3. APD: Performance 2015-11-12 3 Distorted bunch profile “Phantom” bunches “Phantom” bunch signal typically decreases during the fill Mechanism not fully understood… Possible cause: bias voltage ripple (>GHz) leading to sensitivity fluctuations and avalanche onset.

4. Hybrid: Intended use (1) 2015-11-12 4 Doublets Satellites Doublet train, B1 (Fill 4164) vdM-scan: Ghost & Satellite fraction Hybrid significantly better than APD Flattop

5. Hybrid: Intended use (2) 2015-11-12 5 B1 Satellite & Ghost map (vdM scan, Aug 25) =Filled/masked bucket Abort Gap

6. Hybrid: Bonus 2015-11-12 6 Abort gap populationSynchronous phase shift, Bunch by bunch

7. (No baseline subtraction) Raw Beam loss correction Hybrid: Unexpected Most likely beam losses(?) Bunched signal from wrong beam corrupts measurement …can be corrected Long term damage? Profile of opposite beam is detected 2015-11-12 7 B1 structure seen by B2 hybrid

8. Outlook Install BSRL equipment on removable breadboard YETS2016 2015-11-12 8 Current location New location? Fibre

9. Backup 2015-11-12 9 Hybrid abort gap estimate and measured beam loss