scintillators testing at prague

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)

19.6.2012

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

19.6.2012

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

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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

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V. Vorobel, SuperNEMO meeting, Bordeaux

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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

19.6.2012

V. Vorobel, SuperNEMO meeting, Bordeaux

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Backup

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V. Vorobel, SuperNEMO meeting, Bordeaux

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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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V. Vorobel, SuperNEMO meeting, Bordeaux

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Stabilization

Dubna spectrometer #2

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V. Vorobel, SuperNEMO meeting, Bordeaux

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V. Vorobel, SuperNEMO meeting, Bordeaux

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