CAT of AGATA detectors & AGATA Week July 2008 CAT of AGATA detectors & The AGATA triple cluster detector University of Cologne Andreas Wiens B. Birkenbach, B. Bruyneel, J. Eberth, H. Hess, D. Lersch, G. Pascovici, P. Reiter - IKP Cologne H.-G. Thomas - CTT

Overview Acceptance test results Status of the triple cluster detectors Crosstalk in triple cluster detector Summary

Experimental setup & specifications Core at 1.3MeV: ≤ 2.35keV at 122keV: ≤ 1.35keV Segments at 1.3MeV: ≤ 2.30keV, mean ≤ 2.10keV at 60keV: ≤ 1.30keV, mean ≤ 1.20keV Crosstalk ≤1‰

Test results A002 & A003 after gluing core contact A002 detector accepted A003 detector accepted

Test results C004 detector accepted

Test results A004 Very good performance at low energies back seg. F5 FWHM: 2.66 keV front seg. A1 Very good performance at low energies low impurity concentration: crystal properties? trapping? detector rejected FWHM: 2.83 keV

Test results B001 Core 6 µs 2,66 2,77 3 µs 2,43 2,45 A3 3,03 3,06 2,44 1,2 MeV 1,3 MeV Core 6 µs 2,66 2,77 3 µs 2,43 2,45 A3 3,03 3,06 2,44 2,53 C3 2,48 2,16 2,29 C3 leakage current damage at the contact or the implantation layer of A3 and C3 ? detector rejected 2.06 keV @ 59.5 keV

Test results B004 First delivery: Dec 08 B004 – missing segment F6 after first delivery Second delivery: Jun 08 Core @ 59.5/122 keV FWHM: 1.5/1.6 keV @ 1.3 MeV FWHM: 2.7 keV High noise level at segment F4 (100 mV after Amp, without HV) 60 keV 122 keV Core 6 µs 1.5 1.6 3 µs 1.55 F4 1.9 1.87 Segments of sector F grounded: Core @ 1.3 MeV FWHM: 2.72 keV FWHM: 1.74 keV @ 122 keV Core 5000 V

C001 in new TU Munich cryostat delivered to Liverpool for scanning Mean FWHM @ 60 keV: May 06: 1147 +/- 63 eV Jan 08: 1083 +/- 61 eV Mean FWHM @ 1.3 MeV: May 06: 2.13 +/- 0.1 keV Jan 08: 2.1 +/- 0.1 keV

Summary acceptance tests B001 06/07 Padova Rejected - damage of contacts of segments A3 & C3 A002 München Accepted C004 09/07 Ankara A004 Rejected - low impurity concentration and/or trapping A003 10/07 Liverpool B004 12/07 Tested, not in specification A005 Uppsala Test ongoing (Saclay & Cologne) C005 Test at Saclay B005 07/08 Test at Cologne

Asymmetric AGATA Triple Cryostat Mechanical precision of the end caps bending under vacuum within tolerances Exact positioning of the detectors inside the triple endcap Spacing 0.5 mm LN2 consumption Thermal properties HV box fits Tolerances spacing between crystals 0.5mm Tolerances endcaps 0.5mm ? Temp 55deg (14h) LN2

Tripel Cluster 1 Energies: Single vs Triple cryostat Resolution 60keV line Resolution 1.33MeV line A001 – FWHM [keV] Excellent energy resolution in new triple cluster Mean values segments @ 60 keV : A001 : 1011 +/- 53 eV B002 : 1039 +/- 70 eV C002 : 965 +/- 63 eV especially at low energies (electronic noise): - glued detector  less microphonics - HEKO  AGATA preamp - electronic assembly (grounding, cabling) B002 – FWHM [keV] C002 – FWHM [keV] Improved energy resolution especially at low energies (electronics dominated) - glued detector less microphonics - final preamp electronic assembly (grounding, cabeling) Message : better than in single cryostat – specification easily met

X Cross talk : intro Core to seg Xtalk = understood! Segment labeling: Sectors: A...F Rings: 1...6 Core to seg Xtalk = understood! A2..A6 B1 F1 X

Smallest capacities in ring 2 D2 C2 A2 B2 E2 F2

Smallest capacities in ring 2 B2 C2 E2 F2 D2 A2

No cross talk between detectors in Triple Cryostat Sector A Sector F Sector A Sector F Core B Core C Sector A Sector F B002 Core A Core C C002 Core A Core B

Tripel Cluster 2 Energies: Single vs Triple cryostat Resolution 60keV line Mean values segmens @ 60 keV : A001 : 1053 +/- 65 eV B002 : 995 +/- 73 eV C002 : 1149 +/- 105 eV preliminary

AGATA Triple Clusters: Summary and outlook AGATA Triple Cluster Detectors operational: first triple: cryostat, mechanics, vacuum o.k. seg-preamps, core preamp & pulser o.k. energy resolution o.k. no cross talk between detectors second triple: commissioning phase - Outlook: Demonstrator at Legnaro: - transport to Legnaro of ATC1 in July 2008 - assembly of third triple constrained by available detectors ATC1 ATC2 ATC3

Core pulser result: measurement of segment capacities in 1. triple