GTK GAS COOLING SYSTEM Marco Statera, Vittore Carassiti, Ferruccio Petrucci, Luca Landi, Stefano Chiozzi, Manuel Bolognesi NA62 - GTK working group meeting

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera1

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera2

DESIGN REQUIREMENT THE DESIGN OF THE DETECTOR REQUIRES TO MINIMIZE THE MATERIAL BUDGET THE COOLING SYSTEM CONCEPT DESIGN FOLLOWS THE SAME REQUIREMENT Na62 GTK working group meeting, CERN Marco Statera3 Cooling system Supporting plate Heat flux HEAT FLUX UNIFORM: HF = 2 W/cm 2 TEMPERATURE GRADIENT > 30° C CYLIDRICAL WALL 40  m FLAT WALL 10  m SHARING THE JOBS : CYLINDRICAL WALLS SUPPORTING THE PRESSURE FLAT WALLS DEFINING THE FLOW CROSS SECTION MATERIAL BUDGET X 0 = %

MAKING THE PARTS Na62 GTK working group meeting, CERN Marco Statera4 ALL PARTS MADE BY FERRARA WORKSHOP

MECHANICAL TESTS KAPTON CREEP – working pressure Wp = 1 bar – Test pressure Tp = 2Wp = 2 bar – AFTER TWO Tp NO EVIDENCE OF CREEP KAPTON FAILURE PRESSURE – safety factor (40  m) Wp QUALITY OF THE JOINT KAPTON-RESIN-ALUMINUM – safety factor 1.9 Na62 GTK working group meeting, CERN Marco Statera5

OPTIMIZATION Na62 GTK working group meeting, CERN Marco Statera6 injection channels : share the flow rate & avoid the temperature drop on the inner edge of the detector lateral channels : the flow is injected cooled until the exit

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera7

ROOM TEMPERATURE MEASUREMENT Na62 GTK working group meeting, CERN Marco Statera8 THERMO-CAMERA SILICON WINDOW DETECTOR MOCK UP & DISTRIBUTING CHANNELS

THERMAL MODEL VALIDATION Na62 GTK working group meeting, CERN Marco Statera9 THERMOCAMERA IMAGE THERMAL MODEL

TEST BENCH AND READOUT Na62 GTK working group meeting, CERN Marco Statera10 FLOW RATE POWER & TEMPERATURES VACUUM TEMPERATURES VS TIME FLOW

TEMPERATURE SENSORS Na62 GTK working group meeting, CERN Marco Statera11 FLOW T0 T10 T4T3T2 T1 T9 T5 T6T7T8 T11 T12 T13 T14

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera12

RESULTS - 1 Na62 GTK working group meeting, CERN Marco Statera13 T0T1T2T3T4T5T6T7T8T9T10T11T12T13T14W Flow l/min 11,715,30,71,013,818,5 26,034,015,50,41,81,00,3-1, ,020,00,31,218,523,223,432,644,019,3-0,70,0-1,6-3,2-4, ,733,52,64,627,534,436,248,667,833,22,81,9-0,6-1,8-1, ,323,4-6,4-4,917,423,224,837,056,322,0-6,4-8,0-11,3-12,7-12, ,02,0-25,0-24,3-4,10,83,315,334,53,0-26,0-27,5-30,8-31,7-31, ,044,38,59,935,442,345,860,082,543,68,35,92,40, ,5 32 W – 48 W – 56 W results Pdigital/Psensor = W: different sensor temperatures regulating the flow (4 l/min)

RESULTS- 2 Na62 GTK working group meeting, CERN Marco Statera14 measured temperatures of the sensor area (T10-T14) ΔT < 6° C average temperature regulated by flow (+5° C ÷ -30° C )

RESULTS - 3 Na62 GTK working group meeting, CERN Marco Statera15 measured temperatures of digital area (T0-T4 and T5-T9) and sensor area (T10-T14) set sensor and digital nominal power flow regulation reduce max temperature and gradient

TYPICAL MEASUREMENT - 1 Na62 GTK working group meeting, CERN Marco Statera16 sensor temperature regulation by flow at different powers

TYPICAL MEASUREMENT - 2 Na62 GTK working group meeting, CERN Marco Statera17 4 W -> 56 W Pdig/Psens= W Pdig/Psens=3.7 the system is optimized for the asymmetric power distribution T0T1T2T3T4T5T6T7T8T9T10T11T12T13T14Wl/min ,5-45,4-45,6-36,4-31, ,3-16,7-31,86,31, ,532136

HEATERS & MATERIAL 18 beforeafter digital resistance measured values [Ω] before and after the test of mockup #11 avg = 55.3 Ω std = 6.3 Ω Na62 GTK working group meeting, CERN Marco Statera effect on temperature distribution local power distribution material thermal properties

EXTRAPOLATION Na62 GTK working group meeting, CERN Marco Statera19 resistor spread increases longitudinal and trasversal gradient given a flow and power T i = T x R i / 60 R i measured; 60 Ω nominal R; correction (extrapolation) up to 20° C

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera20

THE SYSTEM COOLING: – GAS FROM LIQUID THE SYSTEM – how it works and costs RUN AND MAINTENANCE PROCEDURES – pumpdown, cooldown, time constants : fast ramp up/down, emergency warm up, 1 heater broken INTERLOCK Na62 GTK working group meeting, CERN Marco Statera21

GAS FROM LIQUID Na62 GTK working group meeting, CERN Marco Statera22 Pro liquid is a reserve of gas fast restart time after an emergency stop cooling power: K safe shut off: the emergency valve reduces the dewar pressure Cons needs cryogenic liquid pumping vapor COST 4 systems: 370 k€ the gas above a liquid bath is forced into the cooling pipes and cooled down by a cold head the pressure of the dewar is kept constant; a heater at the cold head also prevents low pressures the flow is regulated by the valve additional relief valve

THE SYSTEM gas from liquid solution is proposed three stations: one coling station is not cheaper since the cost of the cryogenic lines. Three pumping/cooling systems are required each station is independent (no crosstalks) Installation side: Jura or Saleve 20 m of cryogenic lines: – the cooling station few meters far from the beampipe – the outer diameter is about 35 mm, we asked for a 100x100 mm 2 cross section in the trench the control system (PLC) is outside the cavern Na62 GTK working group meeting, CERN Marco Statera23

RUN AND MAINTENANCE RUN refill liquid nitrogen start the coldhead emergency stop -> some nitrogen gas lost; the liquid is a reserve. NO access required 6 months running SAFETY cryostat: pressurized vessel cold nitrogen standard issues to be discussed with lab safety staff MAINTENANCE every 9000 hrs (12 months run) coldhead maintenance (2 skilled persons for 2 days): head o-ring kit and compressor filters valves check (emergency test) Na62 GTK working group meeting, CERN Marco Statera24

PROCEDURES pumpdown cooldown turning on and regulation warmup one chip failure emergency Na62 GTK working group meeting, CERN Marco Statera25

PUMPDOWN Na62 GTK working group meeting, CERN Marco Statera26 turbopump nominal pumping speed: 70 l/s (N 2 ) typical working pressure < 1 E-5 mbar Improve vacuum performance: faster pumpdown and lower ultimate pressure accurate handling/cleaning UHV materials vacuum before installing

COOLDOWN Na62 GTK working group meeting, CERN Marco Statera27 stable cooldown conditions set temperature and cooling speed by flow regulation i.e. regualting the valve COOLDOWN TEMPERATURES AND FLOW

TURN ON AND REGULATION Na62 GTK working group meeting, CERN Marco Statera W (16 –> 24 W) ΔT 25 °C in 35 s the full digital power on (48 W) requires control (heater) regulating the flow 10 seconds compatible with a few seconds full on/off valve

TURN ON PROCEDURE a heater resistor is required (on the N 2 line) use of an additional temperature sensor (a TC not on the sensor) increase the flow regulating the board temperature by the heater -> nominal flow (sensor temperature > -20 Celsius) turn on the sensors and turn off the heater regulate the SENSOR temperature by the valve (flow) Na62 GTK working group meeting, CERN Marco Statera29

WARM UPAND CHIP FAILURE Na62 GTK working group meeting, CERN Marco Statera30 self warm up – cooling turned off max warming speed about 40 K/h external heating not required temperature drop in case the heater (chip) fails is about 10 power 32 W the system reads one temperature, may change the flow and/or set an allarm

EMERGENCY Na62 GTK working group meeting, CERN Marco Statera31 about 25 seconds with the valve closed: temperature rise 4 seconds power is stopped no need of very fast interlock: about 1 second May 2011

INTERLOCK INPUT (4) – sensor temperature (average or 1 point) – TC on the board (requested) – chip power supply current – emergency signal CONTROL – regulating valve opening (flow) – gas heater – bypass valve (cryostat) – coldhead + coldhead heater OUTPUT (3) – sensor temperature (crosscheck) – regulating valve opening – status (OK/alarm) PLC (fully hardware – interlock & control) – outside the cavern – no interaction during run – RATE: about 1Hz (typical 10Hz) Na62 GTK working group meeting, CERN Marco Statera32

PROGRAMS COOLDOWN – stable flow (i.e. valve opening) – regulating temperature by TC on the board STANDBY – preparation before run and after run – TC on the board useful RUN – control loop: Si temperature valve opening WARM UP EMERGENCY – close the regulating valve (normally closed) – open the safety valve of the dewar (1 atm in seconds) – turn off the cryohead (and heating to room temperature if possible) – emergency signal output Na62 GTK working group meeting, CERN Marco Statera33

OUTLINE DESIGN CONCEPT AND OPTIMIZATION TEST SETUP RESULTS SYSTEM ASSEMBLY PROCEDURE CONCLUSIONS Na62 GTK working group meeting, CERN Marco Statera34

INTEGRATION – PHASE 1 TEFLON MASK ALIGNER SLIDING SUPPORT GUIDES FIXED SUPPORT mask aligner : the supports are inserted in the reference places UNDERCUT FITTING THE PCB THICKNESS 35Na62 GTK working group meeting, CERN Marco Statera

TEFLON MASK ALIGNER PCB SUPPORTING PLATE REFERENCE PINS Mounting the mask aligner in the PCB supporting plate TEFLON MASK ALIGNER SEAT SLIDING SUPPORT GUIDES & FIXED SUPPORT 36Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 2

REFERENCE PINS MASK ALIGNER Glueing the sliding support guides and the fixed support on the PCB PCB SUPPORTING PLATE 37Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 3

SLIDING SUPPORTS PCB inserting the sliding support after the resin curing 38Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 4

PCB SUPPORT PLATE PCB mounting PCB & detector supports on The PCB support plate DETECTOR SUPPORTS 39Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 5

gluing the detector on the detector supports PCB SUPPORT PLATE PCB DETECTOR REFENCE UNDERCUT REFERENCE PINS DETECTOR SUPPORTS DETECTOR 40Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 6

41Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 7 INNER REFERENCE CENTRE OF THE DETECTOR OUTHER REFERENCE CENTRE OF THE DETECTOR The centre of the detector is referred outside the vacuum vessel DETECTOR CENTRE (NOMINAL)

bonding the wires WIRE BONDS 42Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 8

ASSEMBLING THE TWO HALF VESSELS 43Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 9

MOUNTING THE TUBES 44Na62 GTK working group meeting, CERN Marco Statera INTEGRATION – PHASE 10

THERMAL SHOCK ROOM TEMPERATURE TO 77 K 45Na62 GTK working group meeting, CERN Marco Statera TEST OF THE PCB & DETECTOR ASSEMBLY PROCEDURE

TEAM Na62 GTK working group meeting, CERN Marco Statera46 Ferruccio PETRUCCI Vittore CARASSITI (mech. service) Marco STATERA (vacuum & cryo service) Manuel BOLOGNESI (electr. service) Stefano CHIOZZI (electr. service) Angelo COTTA RAMUSINO (electr. service) Luca LANDI (mech. service) Roberto MALAGUTI (electr. service) Michele MELCHIORRI (mech. service) Claudio PADOAN (electr. service) Stefano SQUERZANTI (mech. service) design, simulation, tests, development & construction

CONCLUSIONS -1 design concept and optimization – mechanical design and test: safety factor >2 – material budget X o = % optimization – room temperature and working condition test benches – FEM flow simulation validated the results we have shown – the final prototype tested in working conditions: power, power distribution, temperature and vacuum – the system has been tested up to 56 W (actual power distribution) – regulation of the sensor temperature by the flow rate: 0 ÷ -20° 48 W – the system can work with different power distributions: 32 W homogeneus power distribution results Na62 GTK working group meeting, CERN Marco Statera47

CONCLUSIONS - 2 system overview – cooling method: gas from liquid nitrogen – installation requirements – no access required during a full run – measured parameters for different working states control and interlock – input/output defined – running programs defined – interlock conceptual design for different working states integration – realistic integration sequence – three points holder assembled and tested in severe thermal conditions Na62 GTK working group meeting, CERN Marco Statera48