Xenon Detector Group Contents Cryostat Construction Detector Preparation

  • Slides: 30
Download presentation
Xenon Detector Group

Xenon Detector Group

Contents • Cryostat Construction • Detector Preparation • Schedule 1

Contents • Cryostat Construction • Detector Preparation • Schedule 1

Cryostat Construction • Xenon Cryostat is NOT DELIVERED YET Cryostat Construction Cold Vessel •

Cryostat Construction • Xenon Cryostat is NOT DELIVERED YET Cryostat Construction Cold Vessel • Thin Window Welding • PMT Support Inst. Test • Vacuum Leak Test • Pressure Test • Cryogenic Test Honeycomb Panel Construction • Pressure Test • Low-Temp Test 2

Schedule Reported in the Last Meeting • • Week 19 -23 June: – Warm

Schedule Reported in the Last Meeting • • Week 19 -23 June: – Warm vessel: Complete welding of all nozzle (3 days). – Cold vessel: Complete welding of CF 100 flanges, braze the cooling tube (3 days) Welding test of the windows (2 days) – New foil fabrications (4 days). – Define Honeycomb materials and geometry (2 days) delivery (15 days) Week 26 -30 June: – Test box preparation: warm window test box (1 day); cold window test box (3 days). – Welding of warm window on the test box (2 days) + helium leak test (1 day)+ mechanical test (1 day). – Machining of cold vessel (5 days). Week 3 -7 July: – Welding of cold window on the test box (2 days)- helium lesk test (1 day). – New honeycomb delivered – mechanical test cold window (1 day). – Welding window on cold vessel (2 days) Week 10 -14 July: – Test warm vessel (2 days). – Helium test of cold window (1 day) – Honeycomb mounting and cold test preparation (1 day) – Pressure test cold vessel, 4 bar, (1 day) • • • Week 17 -21 July: – Dry out cold vessel (1 day)- helium leak test of metallic sealing on covers (1 day). – Mounting of the phototube supporting structure (2 days) – Welding of the L bracket to hold the arches (phototube supporting structure) (1 day) – Installation of super insulation and temperature sensors (1 day) Week 24 -28 July: – Alignment and vessel integration (3 days) – Bellows welding (3 day) Week 31 July - 4 Agust: – Helium leak test on the welds (1 day) – Internal polishing (3 days) – Cleaning and dryout (2 days) Week 7 - 12 August: – Preparation and installation of equipmnets for the cryocenic test (1 day) – Cryogenic test (4 days) Week 14 - 18 August: – Helium leak test of cold vessel (2 days) – Prepartation of shipmenet (2 days) Week 21 - 26 August: – Delivery to PSI End Oct End Dec 3

Why is Cryostat Construction Delayed? • Thin window welding and related tests took longer

Why is Cryostat Construction Delayed? • Thin window welding and related tests took longer time than expected, which is now successfully completed. • PMT support did not fit the cold vessel wall because of deformation that had appeared during construction process. 4

PMT Support Installation Test • Cold vessel construction procedure Assemble and weld Thin window

PMT Support Installation Test • Cold vessel construction procedure Assemble and weld Thin window welding Machining Leak test Honeycomb panel Installation into the warm vessel • Test was performed on 29/Sep/06, but … Reality Ideal Xenon coming in. • Several mm gap ~6 mm Support structure cannot come in • LXe R. L. 2. 89 cm 5

Protocol Update • Discussion between SIMIC and INFN – Update schedule including remachining of

Protocol Update • Discussion between SIMIC and INFN – Update schedule including remachining of the cold vessel wall – Check points at milestone activities • He Leak Test, Pressure Test, etc. – Assign another SIMIC engineer who can respect the schedule in a cautious manner – In case of schedule slippage without any acceptable reason, we will stop SIMIC and continue at a different manufacturer. 6

Remachining of the Inner Vessel Wall • Aviolamer (Pianezza, TORINO) – 6 -axis milling

Remachining of the Inner Vessel Wall • Aviolamer (Pianezza, TORINO) – 6 -axis milling machine – 3 D Coordinate Measuring Machine 632. 1 631. 6 632. 0 634. 5 635. 9 7

PMT Support Installation Test • The welded thin window was removed for this procedure

PMT Support Installation Test • The welded thin window was removed for this procedure • Scraped away the inner wall by 5 mm at maximum • PMT support successfully installed • Checked with a gap gauge of 200 mm with the supporting structure installed on 22/Jan/2007 8

Vacuum Leak Test with Metal Gasket • He vacuum leak test of the cold

Vacuum Leak Test with Metal Gasket • He vacuum leak test of the cold vessel with Helicoflex sealing (metal gasket) at a sensibility of 10 -9 cc atm/sec on 14/Dec/2006 • OK at the upstream side, but not OK at the downstream side because of welding • Fixed by filling the hall with a metal piece, and tested again on 18/Dec/2006 9

Pressure Test • Test up to 4 bar on 19/Dec • Displacement measured at

Pressure Test • Test up to 4 bar on 19/Dec • Displacement measured at 4 different locations • The test was repeated twice – 1 st test OK – 2 nd test • Water leak at the upstream flange, which was later found to be due to scratch on the groove. • This was fixed and checked in another vacuum leak test performed on 22/Dec/2006 4 Bar! 10

Comparison with Simulation • Displacement measured at 4 bar 1. 2 mm 0. 55

Comparison with Simulation • Displacement measured at 4 bar 1. 2 mm 0. 55 mm 1 4 3 Modeling 1. 3 mm Dial. N. 1 2 1. 25 mm 1. 7 mm Dial. N. 2 11

Thin Window Welding Again • The honeycomb panel and PMT structure are used to

Thin Window Welding Again • The honeycomb panel and PMT structure are used to guarantee that there is no gaps between them. SIMIC is now drilling the blind thread holes to restrain the panel. üThin Window Welding üPMT Holder Inst. Test üVacuum Leak Test üPressure Test • Cryogenic Test Position of the blind holes 12

Honeycomb Panel Production

Honeycomb Panel Production

Honeycomb Panel – Brief Retrospect • The 1 st panel broke down in pressure

Honeycomb Panel – Brief Retrospect • The 1 st panel broke down in pressure test as reported in the last meeting • New (2 nd) panel was designed – Honeycomb thickness 19 mm 26. 5 mm – High module prepreg 0. 75 mm 1 mm – Transition with fabric only Taper Transition Honeycomb panel Thin window welded on the cold vessel 1 st honeycomb panel pressure test 1 st panel OK on this side 2 nd panel 14

Pressure Test of the 2 nd Panel • Pressure test was stopped at 2.

Pressure Test of the 2 nd Panel • Pressure test was stopped at 2. 5 bar to check the panel internal surface – Small crack on the surface • The panel was tested again with proper SIM between the panel and test box – Curvature of the panel OK – Curvature of the test box NO SIM • Succeeded to apply up to 4 Bar – Repeated 4 times – Break down at the end Pressure 15

The 3 rd Panel • • Internal reinforcement at the edges. Fiber with lower

The 3 rd Panel • • Internal reinforcement at the edges. Fiber with lower module but with a better Elongation (T 300, used in aerospace applications with over 20 year service history). – 1. 5 mm prepreg thickness with 8 piles (1 mm in the 2 nd panel • Space-approved Resin epoxy (Hysol EA 9361) Internal reinforcement “Coca-Cola can” can shape 16

Construction of the 3 rd Panel • The 3 rd panel requires more intermediated

Construction of the 3 rd Panel • The 3 rd panel requires more intermediated construction steps and a lot of preparation of parts prior to gluing and assembly 1. 2. 3. 4. 5. Forming the external skin Forming the honeycomb Machining the honeycomb Forming the external skin Gluing the reinforcement to the central honeycomb in the primary mold 6. Gluing the external skin to the honeycomb using paste adhesive 7. Gluing the internal skin to the rest parts with paste adhesive Two additional molds are necessary External skin Internal skin Central honeycomb Internal reinforcement 17

Construction Status of the 3 rd Panel • Delivery to Pisa in this week

Construction Status of the 3 rd Panel • Delivery to Pisa in this week • Pressure and low temperature test soon after that before bringing to SIMIC on 21/Feb Rohacell Z reinforcement Outer Skin Honeycomb glued to the Z reinforcement and rohacell Inner skin 18

Updated Construction Schedule Cryogenic Test Shipping to PSI 19

Updated Construction Schedule Cryogenic Test Shipping to PSI 19

Detector Preparation Xenon Storage Cables and Related Electronics Na. I Detector for Pi 0

Detector Preparation Xenon Storage Cables and Related Electronics Na. I Detector for Pi 0 Calibration C-W Proton Acc Peter’s Presentation Nickel 9 Me. V Gamma Generator

Xenon Storage • • ~900 L in liquid, largest amount of LXe ever liquefied

Xenon Storage • • ~900 L in liquid, largest amount of LXe ever liquefied in the world Very stable – Pressure raise 0. 003 MPa/h w/o cooling – 0. 111 MPa 0. 2 MPa in 44 hours GXe pump (10 -50 L/min) Heat exchanger GXe storage tank Getter+Oxysorb Cryocooler (100 W) LN 2 Cryocooler (>150 W) Liquid pump (100 L/h) Purifier LXe Calorimeter Liquid circulating purifier 1000 L storage dewar 21

Cables and Related Electronics • Signal and HV cables have been already laid down

Cables and Related Electronics • Signal and HV cables have been already laid down • Signal Splitter and HV power supply are ready, too • HV Controller – GUI for Xe HV control – Runs in monitor mode of meganalyzer – 2 D PMT map with markers – Some more functions – Will be tested soon with real HV modules 22

Na. I Detector for Pi 0 Calibration • • • 9 Na. I (Tl)

Na. I Detector for Pi 0 Calibration • • • 9 Na. I (Tl) Crystals, 62. 5 x 305 mm Each viewed by 2 APDs (5 mm x 5 mm) Electronics Test with MEG DAQ (DRS) at Pi. E 5 – Cosmic-Ray data – Need to improve S/N • • APD with larger active are 2 x 5 mm 10 mm x 10 mm 60 o COMIC DRS Data 23

24

24

25

25

New Neutron BG Measurement • Multiple locations with different detectors (Pi. E 5 in

New Neutron BG Measurement • Multiple locations with different detectors (Pi. E 5 in Dec/2006) – – C Bonner Sphere Na. I activation method with Cd foil wrapping Total flux 3. 7 n /sec/cm 2, Thermal flux 0. 5 n /sec/cm 2 Small enough for Xe Detector PMT operation A B m beam • 4” x 4” cylinder; • activation technique • thermal and non-thermal separattion by using Cd-wrapping method • Precise measurement of thermal neutron flux and estimate of non thermal neutron flux. • 3 He counter • 2”, 3”, 5”, 8”, 10”, 12” spheres • Neutron energy spectrum determination: • sphere response functions • numerical unfolding codes. 26

m radiative decay e Lower beam intensity < 10 Is necessary to reduce pilem

m radiative decay e Lower beam intensity < 10 Is necessary to reduce pilem ups n n Better s , makes it possible 7 t to take data with higher beam intensity (rough) relative timing calib. < 2~3 nsec A few days ~ 1 week to get enough statistics p 0 LED Laser PMT Gain Higher V with light att. p- + p p 0 + n Can be repeated frequently p 0 (55 Me. V, 83 Me. V) p- + p + n (129 Me. V) Laser 10 days to scan all volume precisely alpha (faster scan possible with less points) LH 2 target e+ Xenon Calibration PMT QE & Att. L Cold GXe LXe e- Proton Acc Li(p, )Be Nickel Generator Li. F target at COBRA center K 17. 6 Me. V Bi Tl F Li(p, 1) at 14. 6 Me. V Li(p, 0) at 17. 6 Me. V New ~daily calib. Can be used also for initial setup off 9 Me. V Nickel γ-line on quelle Illuminate Xe from the back Source (Cf) transferred by comp air on/off 3 cm 20 cm Na. I Polyethylene 0. 25 cm Nickel plate 27

Schedule • Available online at – http: //meg. web. psi. ch/subprojects/install/xenon. html • April

Schedule • Available online at – http: //meg. web. psi. ch/subprojects/install/xenon. html • April • Cryostat delivery to PSI • Alignment at Pi. E 5 • Start of PMT installation • May • Complete PMT installation • Check electrical connection • Start evacuation • June • Pre-cooling • Liquefaction • Purification • Liquefaction (liquid transfer) will end on 17/June After the detector is ready, 1. PMT HV adjust, gain calibration, and a-source (and Cosmic-Ray) data acquisition (2 Weeks) 2. Proton Acc DAQ (2 Weeks) 3. p 0 run (3 Weeks, 10 Days full DAQ) 17/June End of Liquefaction 4. Radiative m decay run with lower beam intensity (2 Weeks) 28

Summary • Cryostat construction – Many problems occurred, but they are getting solved one

Summary • Cryostat construction – Many problems occurred, but they are getting solved one by one – Honeycomb panel will be delivered to Pisa in this week and tested before bringing it to SIMIC – Cryostat delivery to PSI in April after a cryogenic test • Detector preparation is in good condition – Calibration procedures • pi 0 • C-W Acc • Nickel – Neutron measurement performed again • BG level is expected to be small enough for the xenon detector operation 29