1. Scintillators testing at Prague
Vít Vorobel, Aivaras Zukauskas, Dimitri Mathian
Petr Pridal, Fadahat Mamedov
Guillaume Lutter, Emmanuel Chauveau
Oleg Kochetov
(Financed by FMP ChU, IEAP CTU, JINR Dubna)
V. Vorobel, SuperNEMO meeting, Bordeaux

2. V. Vorobel, SuperNEMO meeting, Bordeaux
Outline
Spectrometers - hysteresis, vacuum, calibration
Scintillator testing setup, stability
X-wall blocks (Envinet) scan
V. Vorobel, SuperNEMO meeting, Bordeaux

3. “Spectrometers” Dubna #1 Dubna #2 (in BlackBox) Praha
Best reached vacuum ~100 Pa in all three spectrometers
V. Vorobel, SuperNEMO meeting, Bordeaux

4. V. Vorobel, SuperNEMO meeting, Bordeaux
Setup
NEMO3 PMT 5 inch + cookie inside steel tube (mag shielding)
Wrapped scintillator block
Aluminium frame supporting block with PMT
DeltaE detector - 100mm PVT + 2 PMT
Spectrometer
XY-table
V. Vorobel, SuperNEMO meeting, Bordeaux

5. V. Vorobel, SuperNEMO meeting, Bordeaux
Setup
Black Box 100 x 130 x 130 cm
PMTs NEMO-3 5’.
Delta E mm PVT Eljen foil, 2 PMTs in coincidence
Signal readout – Digitizer CAEN V1720, 8 channel, alternatively Amplifier + ADC.
Monoenergetic electron source - “Spectrometer”
Power Suply TTi, PC controlled.
magnet yoke - low hysteresis material.
90Sr, 370MBq
Spectrometer calibration
Si detector, 1 mm thickness, 20 mm2.
207Bi, 100 kBq.
XY-table Range 45 x 45 cm. Control with PC serial port
V. Vorobel, SuperNEMO meeting, Bordeaux

6. V. Vorobel, SuperNEMO meeting, Bordeaux
Calibration
Bi207 used for calibration of Si detector (1 mm thickness)
FWHM ~20 keV at 976 keV
V. Vorobel, SuperNEMO meeting, Bordeaux

7. Spectrometer calibration
260 keV
385 keV
510 keV
640 keV
770 keV
900 keV
1040 keV
1170 keV
1440 keV
FWHM ~30 keV at 1 MeV
V. Vorobel, SuperNEMO meeting, Bordeaux

8. V. Vorobel, SuperNEMO meeting, Bordeaux
Hysteresis
– Set I = -2 A
– Increase gradually current
and measure Eup(I)
– Set I= +2 A
– Decrease gradually current
and measure Edown(I)
Electron energy measured with 1 mm Si detector
Original yoke
Low hyst. yoke
V. Vorobel, SuperNEMO meeting, Bordeaux

9. V. Vorobel, SuperNEMO meeting, Bordeaux
Assembly procedure
Teflon tape 3 layers
Mylar 12 mm 2 layers
Optical grease BC630
V. Vorobel, SuperNEMO meeting, Bordeaux

10. V. Vorobel, SuperNEMO meeting, Bordeaux
Stabilization
Electron energy from spectrometer set 1 MeV
Electrons measured with X-wall block
Peak position vs. time displayed
Stabilization reached in 15 hours
Dubna spectrometer #2
V. Vorobel, SuperNEMO meeting, Bordeaux

11. X-wall blocks – Envinet (exposition 20 min.)
V. Vorobel, SuperNEMO meeting, Bordeaux

12. V. Vorobel, SuperNEMO meeting, Bordeaux
X-wall scintillator # 1 (FWHM at 1 MeV)
V. Vorobel, SuperNEMO meeting, Bordeaux

13. V. Vorobel, SuperNEMO meeting, Bordeaux
X-wall scintillator # 2 (FWHM at 1 MeV)
V. Vorobel, SuperNEMO meeting, Bordeaux

14. V. Vorobel, SuperNEMO meeting, Bordeaux
X-wall scintillator # 3 (FWHM at 1 MeV)
V. Vorobel, SuperNEMO meeting, Bordeaux

15. V. Vorobel, SuperNEMO meeting, Bordeaux
Conclusion
We are ready to characterise the scintillator blocks
FWHM of 3 X-wall blocks measured % (spectrometer resolution not subtracted), measurement will be repeated
Plan
69 X-wall blocks still in Prague
4 of them should be measured in Prague, Bordeaux, UCL for cross-check
V. Vorobel, SuperNEMO meeting, Bordeaux

16. V. Vorobel, SuperNEMO meeting, Bordeaux
Backup
V. Vorobel, SuperNEMO meeting, Bordeaux

17. V. Vorobel, SuperNEMO meeting, Bordeaux
Stabilization
Prague spectrometer
V. Vorobel, SuperNEMO meeting, Bordeaux

18. V. Vorobel, SuperNEMO meeting, Bordeaux
Stabilization
Dubna spectrometer #2
Dubna spectrometer #2
V. Vorobel, SuperNEMO meeting, Bordeaux

19. V. Vorobel, SuperNEMO meeting, Bordeaux
Stabilization
Dubna spectrometer #2
V. Vorobel, SuperNEMO meeting, Bordeaux

20. V. Vorobel, SuperNEMO meeting, Bordeaux
V. Vorobel, SuperNEMO meeting, Bordeaux

21. V. Vorobel, SuperNEMO meeting, Bordeaux
V. Vorobel, SuperNEMO meeting, Bordeaux

22. V. Vorobel, SuperNEMO meeting, Bordeaux
V. Vorobel, SuperNEMO meeting, Bordeaux