Diamond based particle detectors for LHC machine protection

1. Diamond based particle detectors for LHC machine protection analysis of data from Run 1 and detector characterization experiments

2. Motivation • Introduction • Ionisation Chamber Beam Loss Monitors (icBLM) • Diamond Beam Loss Monitors (dBLM) • dBLM characterization • Analysis of LHC dBLM data from run 1 • Specialised experiments with dBLMs at the BTF in Frascati, Italy • Outlook • Conclusion Oliver Stein TE-MPE, olivers.stein@cern.ch

3. Motivation • The detection of beam losses is important for the safe operation of the LHC and its • pre accelerator complex at CERN! • Beam losses are THE indicator for the existence of an (unacceptable) danger in the accelerators: • Beam instabilities • Orbit offsets • Equipment failures • The installed Beam Loss Monitors (BLM) are implemented in the Beam Interlock System •  Losses above the defined thresholds cause a beam dump! Oliver Stein TE-MPE, olivers.stein@cern.ch

4. Introduction >>Ionization Chamber BLM • Ionization chambers (icBLM) are used as the standard BLM • N2 filled cylinder (1.1 bar) • 60 cm length • Parallel electrodes (0.5 cm) • 40µs time resolution (half turn of LHC beam) • More than 3600 icBLMs installed icBLM Electrode setup inside an icBLM icBLMs in IP6 Oliver Stein TE-MPE, olivers.stein@cern.ch

5. Introduction >>Diamond BLM • What happens within 40µs? • New BLM type: diamond based BLMs (dBLM). • 1.5 ns rise time resolution (5 ns FWHM) • Large dynamic range (1 (30) – (1010?) MIPs) E 50 ns Courtesy of M. Hempel Courtesy of M. Hempel Oliver Stein TE-MPE, olivers.stein@cern.ch

6. Introduction >>Diamond BLM • dBLM should detect fast beam losses during LHC operation and help to understand the underlying loss mechanisms. • Abort gap monitoring • Stable beams • Ramp/squeeze • Injection • Extraction Oliver Stein TE-MPE, olivers.stein@cern.ch

7. Introduction >>Current status • 14 dBLMs experimentally installed along the LHC. • Diamond type: pCVD (cividec) 10 mm x 10 mm, wire bonded (8@LHC) • Analysis of dBLM data lead to a better understanding of UFO-events • Special dBLMs designed for high particle fluncies were used during damage tests in HighRadMat. • Diamond type: pCVD (civdec) 5mm Ø, clipped • CMS and Atlas are using dBLMs for beam condition monitoring (BCM). Oliver Stein TE-MPE, olivers.stein@cern.ch

8. Introduction >>Future plans • Making the dBLMs fully operational and improve their usability for Post Mortem checks! •  Additional diagnosticsSteps: • Better understanding of the detector • Detector response (linearity) • Efficiency • Saturation limits • Detection limits • Development of DAQ system Florian Burkart, Oliver Stein, Daniel Wollmann BI, Bernd Dehning et al. Oliver Stein TE-MPE, olivers.stein@cern.ch

9. dBLM characterization • Analysis of LHC dBLM data from run 1 • Specialised experiments with dBLMs at the BTF in Frascati, Italy Oliver Stein TE-MPE, olivers.stein@cern.ch

10. Analysis of LHC dBLM data from run 1 >> detector response • (re) analyzingdBLM data from 2011/2012 • Using UFO events for showing linearity • First attempt to compare dBLM signal with icBLM signals from the same event difficult because a lot of uncertainties affect the analysis Scope channel 1 (C1) Scope channel 2 (C2) 40 db 40 db -6 db -6 db Diamond Diamond 20 db 20 db Scope channel 3 (C3) Scope channel 4 (C2) Beam 1 Beam 2 Oliver Stein TE-MPE, olivers.stein@cern.ch

11. Analysis of LHC dBLM data from run 1 >> detector response • Analysis of UFO signals • Taking data of different signal intensities • Integration of single bunch losses Oliver Stein TE-MPE, olivers.stein@cern.ch

12. Analysis of LHC dBLM data from run 1 >> detector response Linear? Oliver Stein TE-MPE, olivers.stein@cern.ch

13. dBLM characterization • Analysis of LHC dBLM data from run 1 • Specialised experiments with dBLMs at the BTF in Frascati, Italy Oliver Stein TE-MPE, olivers.stein@cern.ch

14. Experiments at the BTF >> Introduction • Characterization of the diamond detectors in at the Beam Test Facility (BTF) at the INFN in Frascati, Italy. • Electron beam at 450 MeV • Adjustable intensity from 1-1010 particles per bunch • Repetition rate 50Hz BTF Oliver Stein TE-MPE, olivers.stein@cern.ch

15. Experiments at the BTF >> Introduction • Goals: • Voltage scans at different electron intensities for measuring the charge collection distance (CCD) of different diamond detectors (100µm and 500µm) • Response and Limits • Beam time from 14.10.-20.10.2013 (Collaboration with UA9, low intensities) • Detectors: • 3 x 100µm (5 mm ) • 2 x 500µm E E Oliver Stein TE-MPE, olivers.stein@cern.ch

16. Experiments at the BTF >> Experimental setup Detector setup Rail on X-Z-Table Beam window calorimeter Oliver Stein TE-MPE, olivers.stein@cern.ch

17. Experiments at the BTF >> Experimental setup Detector holder electron beam Oliver Stein TE-MPE, olivers.stein@cern.ch

18. Experiments at the BTF >> Experimental setup SMA signal cable Detector/PCB LEMO HV cable electron beam Oliver Stein TE-MPE, olivers.stein@cern.ch

19. Experiments at the BTF >> Beam profile measurements Medipixinstalled after the pCVD (10 cm) Beam profiles for different intensities: 1000e, 1850e, 2200e 2250e 1850e 1000e sy sx Integration: 100s Integration: 10s Integration: 10s Fitting measured beam profiles with 2D-gaussian: Oliver Stein TE-MPE, olivers.stein@cern.ch

20. Experiments at the BTF >> Beam profile measurements • Beam size increases with higher intensities • Beam position changes with different intensities • Influence on the measurements? Oliver Stein TE-MPE, olivers.stein@cern.ch

21. Experiments at the BTF >> dBLM measurements Oliver Stein TE-MPE, olivers.stein@cern.ch

22. Experiments at the BTF >> dBLM measurements Oliver Stein TE-MPE, olivers.stein@cern.ch

23. Experiments at the BTF >> dBLM measurements • Large variance of the measured data • Which parameters cause these variances? • Changing beam size between shots? • Changing beam position? • Variation of beam energy 30% 14% Oliver Stein TE-MPE, olivers.stein@cern.ch

24. Experiments at the BTF >> dBLM measurements Oliver Stein TE-MPE, olivers.stein@cern.ch

25. Experiments at the BTF >> dBLM measurements Beam setup 2 Beam setup 1 Oliver Stein TE-MPE, olivers.stein@cern.ch

26. Experiments at the BTF >> data analysis/results • Assumptions: • Gaussian shaped beam • Beam size: • sx: 4.32 mm • sy: 1.57 mm • Max. signal: 75.2 % Oliver Stein TE-MPE, olivers.stein@cern.ch

27. Experiments at the BTF >> data analysis/results • Sensitivity: • Intensity dependency • Variation of relative beam position • Variation of the beam size Oliver Stein TE-MPE, olivers.stein@cern.ch

28. Outlook • Continue data analysis (LHC, Frascati) • Request for own high intensity beam time for finalising measurements • Preparation of experiment setup • Improvement of beam diagnostics, beam size, intensity measurements • Stage system • DAQ optimization (speed, scans,…) • Collaboration with BI for LHC-DAQ system Oliver Stein TE-MPE, olivers.stein@cern.ch

29. Conclusion • Analysis of dBLM data from run1 • Detector linearity shown • Experiments at BTF, Frascati • Detector setup is working • DAQ successfully tested • Data shows variation of detector and calorimeter signals • Measurements at different intensities (low intensities, up to 2000 electrons) • Voltage scans performed •  uncertainties have to be identified •  request for high intensity measurements •  improve beam diagnostics • Preparation/optimization of the experimental setup and DAQ • Analysis of data (LHC/BTF) will be continued Oliver Stein TE-MPE, olivers.stein@cern.ch

30. Thank You! • Any Questions? Oliver Stein TE-MPE, olivers.stein@cern.ch