Time over Threshold Electronics for Neutrino Telescopy

Physics Laboratory School of Science and Technology Hellenic Open University + multiplicity George Bourlis Time over Threshold Electronics for Neutrino Telescopy

ReadOut Electronics 5 PMT Signal Inputs Trigger Output USB Port • HPTDC • 32 channels (LR) – 8 Channels (HR) • 25ps (HR) to 100 ps (LR) accuracy • Self Calibrating 25ps accuracy TDC GPS Input

ReadOut Electronics

EZ-USB FX2 HPTDC CONTROL

Card Debugging Configuration splitter discriminator splitter Input Trigger • Offset of each input • Scale of each input • Timing among input channels

Sample Pulses Input 1

@ “nominal” H.V. gain: ~ 4 105 <charge>/p.e. ~ 0.07pCb <pulse height>/p.e. ~ 1.05mV Rise Time: 1.2 ns Single p.e At the Detector Center • Data - Monte Carlo Prediction Charge (pCb) Charge (in units of mean p.e. charge) The Photomultiplier Tube: PH: XP1912 Gain vs HV Calibration

Charge (pC) 1st Threshold only 1st, 2nd & 3rd Threshold 1st & 2nd Threshold Time Over Threshold (s) Charge versus Time Over Threshold 50mV 15mV 4mV

Charge Parameterization 1st & 2nd Threshold 1st, 2nd & 3rd Threshold

11% 8% Charge Estimation 1st & 2nd Threshold 1st, 2nd & 3rd Threshold - Estimated Resolution ~10% - Better if all thresholds are crossed

Charge Estimation 1st & 2nd Threshold 1st, 2nd & 3rd Threshold - σ=(1.01 ± 0.01) (2 thresholds) - σ=(1.1 ± 0.1) (3 thresholds)

Input Trigger Time (ns)

Time over Threshold Electronics for Neutrino Telescopy