V. Vorobel, SuperNEMO meeting, Bordeaux

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Scintillators testing at Prague

Vít Vorobel, Aivaras Zukauskas, Dimitri MathianPetr Pridal, Fadahat Mamedov

Guillaume Lutter, Emmanuel ChauveauOleg Kochetov

(Financed by FMP ChU, IEAP CTU, JINR Dubna)

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V. Vorobel, SuperNEMO meeting, Bordeaux

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Spectrometers - hysteresis, vacuum, calibrationScintillator testing setup, stabilityX-wall blocks (Envinet) scan

Outline

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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“Spectrometers”

Dubna #1 Dubna #2 (in BlackBox) Praha

Best reached vacuum ~100 Pa in all three spectrometers19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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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

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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Setup Black Box 100 x 130 x 130 cm

PMTs NEMO-3 5’.

Delta E - 100 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

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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Calibration Bi207 used for calibration of Si detector (1 mm thickness) FWHM ~20 keV at 976 keV

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V. Vorobel, SuperNEMO meeting, Bordeaux

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Spectrometer calibration

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FWHM ~30 keV at 1 MeV

260 keV

1440 keV

770 keV

385 keV 510 keV

640 keV 900 keV

1040 keV 1170 keV

V. Vorobel, SuperNEMO meeting, Bordeaux

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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. yoke19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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Assembly procedure

Teflon tape 3 layers Mylar 12 mm 2 layers Optical grease BC630

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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Stabilization

Dubna spectrometer #2

Electron energy from spectrometer set 1 MeV Electrons measured with X-wall block Peak position vs. time displayed

Stabilization reached in 15 hours

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V. Vorobel, SuperNEMO meeting, Bordeaux

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X-wall blocks – Envinet (exposition 20 min.)

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X-wall scintillator # 1 (FWHM at 1 MeV)

V. Vorobel, SuperNEMO meeting, Bordeaux

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X-wall scintillator # 2 (FWHM at 1 MeV)

V. Vorobel, SuperNEMO meeting, Bordeaux

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X-wall scintillator # 3 (FWHM at 1 MeV)

V. Vorobel, SuperNEMO meeting, Bordeaux

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Conclusion

We are ready to characterise the scintillator blocks FWHM of 3 X-wall blocks measured 12.7-14.7 % (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

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V. Vorobel, SuperNEMO meeting, Bordeaux

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Backup

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StabilizationPrague spectrometer

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V. Vorobel, SuperNEMO meeting, Bordeaux

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Stabilization

Dubna spectrometer #2

Dubna spectrometer #2

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Stabilization

Dubna spectrometer #2

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