Digital Electronic Tests at JYFL Pete Jones University

Digital Electronic Tests at JYFL Pete Jones, University of Jyväskylä SAGE / LISA Kick-Off Meeting Daresbury Laboratory, 2 nd September 2005 • • Introduction Synchronisation Tests / TDR Integration Phase I Detector Tests Clover Tests

TNT 2

TNT 2

Synchronisation • TNT uses 100 MHz clock, but currently cannot be used as a ”slave” – Use sync pulses from TDR metronome – Use pseudo-random pulse generator into both TDR and TNT – Merge / Time differences offline

Syncronisation Results • • • Pseudo-random generator shows 0. 6 x 10 -6 cannot be corellated TNT ”dead-time” ~1. 8% (10 k. Hz input) : < 4 us pulses Dead time possible in both systems

In Beam Tests • Idea : Test both analogue and digital electronics in real situation • Test effects of counting rates • Performance more realistic than with sources (multiplicity) • Idea of what kind of gamma-ray array need would be for the future

Test Reaction • 107, 109 Ag(36 Ar, 2 p 2 n)139 Eu • • 160 Me. V β~2. 5% Ib=5 – 50 pn. A Ge count rate 10 -100 k. Hz RITU Gas counter 1 -10 k. Hz

Phase 1 Tests Ge 1 Ge 2 BGO 1 BGO 2 SYNC/RESYNC

Threshold of Digital vs Analogue Lower threshold . . but. . . Higher Background (veto)

Analogue : Effect of Rate (pileup) 100 k. Hz 50 k. Hz 10 k. Hz

Phase 1 : Analogue

Phase 1 : Analogue

Phase 1 : Digital

Phase 1 : Digital

Phase 1 Tests : Summary • Analogue limited by pileup & resolution • Digital offers lower energy thresholds • Veto handling in digital needs some work, as does marking of data • Digital solution improves counting rate up to 40 -50 k. Hz

Clover Tests Angle 1 : 69. 2 o EUROGAM II = 75. 5 o Angle 2 : 117. 5 o EUROGAM II = 104. 5 o Target – detector distance same as in EUROGAM II Detector Resolution ~2. 5 ke. V

Angle 1 : 69. 2 o Clover Ge 44

Angle 2 : 117. 5 o Clover Ge 23

Suppression, Sum & Fold n=2 n=1 Unsup press ”clean”

Diagonal Crystals 4 1 3 2 E 1+3 E 1 ”clean”

γ-γ coincidence matrix sum g 713 g 554 g 323 Clover Ph 1

Digital Data… 70 k. Hz 50 k. Hz 40 k. Hz 20 k. Hz 10 k. Hz

Summary • • Instrument Digital Electonics into TDR : Need some ”TDR” compatability Digital electronics : – seems work well with phase 1, and improves counting capability – Offer lower thresholds – Need some work on veto / data • Clover detector gives as good performance as phase 1 – More efficient – Digital problems need to be solved