Status of the muon veto GERDA Collaboration Meeting LNGS November, - PowerPoint PPT Presentation

Status of the muon veto GERDA Collaboration Meeting LNGS November, 5 th -7 th 2007 Markus Knapp

Overview: muon veto plastic scintillator photomultiplier Cherenkov-Veto „Pillbox“ VM 2000 GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation PET-window delivered PMT 9350KB (ETL) encapuslation delivered delivered further treatment small steel parts mineral oil / μ-metal delivered delivered B20 socket and silicon gel voltage divider delivered delievered polyurethane cable / cable delievered feedthrough delivered GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation D PET-window E delivered PMT 9350KB (ETL) R encapuslation delivered delivered E further treatment V small steel parts mineral oil / μ-metal delivered E delivered I L B20 socket and silicon gel voltage divider delivered E delievered D polyurethane cable / cable delievered feedthrough delivered GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 5 Steps 1. Masterbond glueing 2. Cable soldering 3. Pouring of polyurethane 4. Pouring of silicon gel 5. Oil filling GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 5 Steps g n i r Masterbond e d l o s e l b a c e n a h t e r u y l o P Silicon GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 5 Steps g n i cable soldering l l i f l i O Polyurethane Silicon GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 1. Masterbond glueing GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 2. Cable soldering GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 3. Pouring of polyurethane GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 4. Pouring of silicon gel GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line 5. Oil filling GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line Finished GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

PMT Assembly Line Finished GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation ● prototypes under water ● two prototypes running since 7 months GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation ● pressure test running since 3 months ● two prototypes ● no problems encountered GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Cable feedthrough tests ● vary lengths: x,y,l,h,s ● worst case scenario (cut, minimal lengths) ● running since 7months ● running since 3 months under 2bar pressure ● no problems encountered GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Cable feedthrough tests Test setup Tests under water GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Status of encapsulation GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

VM2000 - Status ● Not ordered ● Problem: Adhesive on backside of foil ● Tests of solubility in water ● CHNS analysis from Euro EA at Tübingen: ● Two samples, one in water, the other continuously heated in water ● no impurities (carbon, nitrogen, sulphur) in water were detected ● not enough glue was solved in water to be detected GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

VM2000 – Absorption VM2000 1.3g=74.2 cm2 in 100 ml water 0,02 0,0175 0,015 absorption 10cm cell 0,0125 0,01 0,0075 0,005 0,0025 0 -0,0025 200 225 250 275 300 325 350 375 400 425 450 475 500 525 550 575 600 Wavelength (nm) 19.01.2007 11 days 18 days 27 days 42 days 104 days 137 days 165 days - Measurement from MPIK – Heidelberg - GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

VM2000 – Attenuation length Attenuation length after 162 days 50 45 40 attenuation length (m) 35 30 25 20 15 10 5 0 200 225 250 275 300 325 350 375 400 425 450 wavelength (nm) not filtered filtered calculated for GERDA - Measurement from MPIK – Heidelberg - GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

VM2000 - Photon spectra - MaGe Simulation results – Photon Spectra GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

VM2000 If there are no objections, we will order the reflector foil VM2000 as soon as possible. GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Time information Bottom PMTs wall1 register more photons, but later wall2 wall3 wall4 bottom GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Time information Bottom PMTs wall1 register more photons, but later wall2 wall3 wall4 bottom ~80 % of photons registered within 40 ns GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Grouping of Photomultipliers ● different FADC channel combinations will be tested ● a simple combination is one PM of the pillbox and one of each ring per FADC ● first results show, high efficiency of more than 98 % possible ● other combinations will be tested soon time window # of fired FADCs efficiency 10 ns 4 FADC 96.4% 10 ns 3 FADC 99.0% 30 ns 4 FADC 98.5% 30 ns 3 FADC 99.5% 50 ns 4 FADC 98.9% 50 ns 3 FADC 99.5% GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Cherenkov veto schedule Friday: Beginning of mass production Tests at Tübingen November: Tests of DAQ with panels at Heidelberg. February: Production of 80 PMTs finished March-September: Tests at Tübingen End of September: Delivery to LNGS October: Mounting at LNGS GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Reports under preparation Time structure and randoms of the Cherenkov light (P. Grabmayr, M. Knapp) Photomultiplier encapsulation and mounting (P. Grabmayr, J. Jochum, M. Knapp, L. Niedermeier, F. Ritter, B. Lubsandorzhiev ) VM2000 (P. Grabmayr, J. Jochum, M. Knapp, L. Niedermeier, F. Ritter, +Heidelberg?) GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen

Thank you GERDA Meeting, LNGS, November, 5 th -7 th 2007 - Markus Knapp, University of Tübingen