1. AGATA 2 nd Prototype Detector Initial Measurements & Evaluation Andrew Boston, Matthew Dimmock, Laura Nelson, Sarah Rigby

2. Singles scan results Overview Resolutions – Cologne, Liverpool - Values quoted are for single LVDS cable & single channel Initial coincidence scan results Summary

3. Analogue Digital ChannelEnergy (MeV) Count Rate (kHz / Channel) FWHM (keV) FWTM (keV) FWHM / FWTM FWHM keV) Core1.1721.101.993.731.872.10 Core1.3321.102.053.911.912.10 A51.1720.451.963.851.961.85 A51.3320.451.983.871.952.00 A61.1720.451.933.741.941.90 A61.3320.451.983.901.971.90 D40.0590.280.971.821.881.15 D40.1220.280.991.891.911.14 E40.0590.280.991.911.931.17 E40.1220.280.991.831.851.17 C21.1720.461.833.391.85- C21.3320.461.963.541.81- D21.1720.461.793.341.87- D21.3320.461.813.391.87- Cologne – Resolution Measurements

4. Liverpool - Pre-amp Signal Measurements Offsets are minimal Noise is very small, minimal pickup with no grounding

5. Liverpool – Resolution Measurements Am – 241

6. Liverpool – Resolution Measurements Am – 241 All channels < 1.25keV

7. Liverpool – Resolution Measurements Am – 241 All channels < 1.25keV Variation is a function of capacitance

8. Co – 60 Liverpool – Resolution Measurements

9. Co – 60 Liverpool – Resolution Measurements Most channels < 2.1keV

10. Co – 60 Liverpool – Resolution Measurements Most channels < 2.1keV Resolutions improve by ~0.2keV when all LVDS connected

11. 920MBq Cs-137 source 60 sec per position 1mm steps 1mm diameter collimator Cs-137 Singles Fine scan Max count rate = 720 cps Background = 40 cps 600keV CFD threshold Accepted triggers = 120 cps 180GB pre-sorted data

12. Core 662kev – Ring gated Increased counts at edges – taper

13. Risetimes – Core 662keV T30 T60 T90 Fast axis – Lattice orientation

14. Risetimes – Core 662keV T30 T60 T90 Fast axis – Lattice orientation

15. Core 662keV & Fold 1, Core T30

16. Core 662keV & Fold 1, Core T90

17. Core 662keV & Fold 1, Segment T30

19. Core 662keV & Fold 1, Segment T90

20. Core 662keV & Energy confined to ring, Core T30

21. Core 662keV, Segment confined to ring, Core T60

22. Core 662keV & Energy confined to ring, Core T90

23. Core 662keV, Seg 662keV,Core T30

24. Core 662keV, Segment 662keV, Segment T30

25. Collimation gap centred on (w.r.t. crystal base): 2mm 13.5mm 29mm 48mm 65mm 83.7mm Physical segmentation depth: 0mm 21mm 36mm 72mm 54mm 90mm 8mm Coincidence Setup Div = 1.5mm Div = 2.1mm

26. Initial scan – Counts per hour

27. 1.4mm 2.8mm

28. Initial scan – Counts per hour 1.4mm 2.8mm

29. Summary Ongoing off-line singles analysis Corrected scan setup following initial coincidence scan line Currently running radial scan across y-axis (4mm steps)

30. Radial scan across y-axis (4mm steps)

31. Summary Ongoing off-line singles analysis Corrected scan setup following initial coincidence scan line Currently running radial scan across y-axis (4mm steps) HELP !!!!!!!!

32. Initial Proposal: Current Plans: Hexagonal or Cubic Grid? Coincidence Grid

33. Initial Proposal: Current Plans: Hexagonal or Cubic Grid? Coincidence Grid Equidistant points ???