MEG – PMT cryogenic test: PURPOSES

1. MEG – PMT cryogenic test: PURPOSES • - SYSTEMATIC TEST OF THE PMT’s FOR MEG IN OPERATING CONDITIONS • BUILD AN EVOLUTIVE CRYOSTAT: • PHASE 1 MANUAL OPERATION WITH LXe EMPTING/FILLING FOR EACH PMT • PHASE 2 MANUAL OPERATION WITHOUT LXe EMPTING • PHASE 3 TEST OF CARTRIDGE OF PMT’s WITHOUT LXe EMPTING • - SETUP A CRYOGENIC LABORATORY AT INFN-PISA • - GET EXPERIENCE IN HANDLING LXe • - OTHER MEASUREMENTS ON LXe • - TESTS ON OTHER PMT’s AND OTHER DEVICES (APD’s, …) • FOR THE MOMENT … PHASE 1 •  1

2. MEG – PMTct – Cryogenic/Vacuum Diagram 2

3. MEG – PMTct - Cryostat 3

4. MEG – PMTct - Cryostat REFERENCE PMT HAMAMATSU R6041Q 4

5. MEG – PMTct - Cryostat TRIGGER PMT HAMAMATSU R7400U-09 a, b SOURCE HOLDER 5

6. MEG – PMTct - Cryostat FIXED SUPPORT FLANGE FOR REFERENCE PMTAND SOURCE HOLDER REFERENCE PMT HAMAMATSU R6041Q SOURCE AND TRIGGER PMT HOLDER 6

7. MEG – PMTct - Cryostat REMOVABLE SUPPORT FLANGE FOR PMTUNDER TEST INSERT HERE GATE VALVES + LINEAR VERTICAL MOVEMENT (PHASE 2-3) TEST PMT HAMAMATSU R6041Q REFERENCE PMT HAMAMATSU R6041Q SOURCE AND TRIGGER PMT HOLDER 7

8. MEG – PMTct - Cryostat CRYOSTAT HEAD FLANGE 8

9. MEG – PMTct - Cryostat INNER VESSEL (LIQUID Xenon) 9

10. MEG – PMTct - Cryostat HEAT EXCHANGER COPPER BODY 10

11. MEG – PMTct - Cryostat N2 OUT LN2 IN LXe TEMPERATURE CONTROLLED HEATING RESISTORS LN2 HEAT EXCHANGER COIL 11

12. MEG – PMTct - Cryostat VACUUM CHAMBER 12

13. MEG – PMTct - Cryostat 13

14. MEG – PMTct – Status of Phase 1 Cryostat • - FULL DESIGN AND MECHANICAL DRAWINGS COMPLETED • - CALL FOR TENDERS MADE AND JOB ASSIGNED TO THE COMPANY CINEL-Vigonza (PD), Italy • - CRYOSTAT DELIVERY EXPECTED BY THE END OF FEBRUARY • ORDERS MADE FOR DRY UHV PUMPING GROUP, LEAK DETECTOR, UHV COMPONENTS, CRYOGENIC BOTTLE, PMT’s … • LABORATORY PREPARATION UNDER WAY 14