1. LAr1-ND Cryogenics Concept David Montanari Neutrino Cryogenics Requirements Meeting 24 September 2014

2. Outline Introduction Building layout Requirements Current concept Outstanding issues Design choices Summary Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept2

3. Introduction The Short-Baseline Neutrino Program (SBN) at Fermilab will study neutrino properties using a combination of detectors: –existing MicroBooNE –new LAr1-ND (Near Detector) –a refurbished ICARUS T600 (Far Detector) These slides describe the current thoughts on the cryogenic system for the LAr1-ND detector. The base design is a membrane cryostat of 129 m 3 (LAr volume) or 180 ton LAr Mass. The cryostat will be housed in a new dedicated building next to the SciBooNE enclosure, where the cryogenic system will be located. The two buildings will be connected with a tunnel through which interconnecting lines will connect the cryostat to the cryogenic system. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept3 Note: it may be possible to increase the sensitivity by increasing the LAr volume. We have looked into extending the width to 5.75 m (from 4.4 m), that is 168 m 3 LAr volume. This will allow the insertion of two (2) 2.5 m wide APAs instead of one (1) 3.65 m wide.

4. Layout for LAr1-ND similar to the LBNE 35 ton prototype 4 LAr/GAr transfer lines Process piping North LAPD LBNE 35 ton Cryostat LAPD/LBNE LAr purification/filtration system LAr/GAr transfer lines Process piping 1.3-2.6 vol change/day David Montanari | LAr1-ND Cryogenics ConceptSep 24, 2014 This is the 3D model of PC-4 with the LBNE 35 ton and LAPD. We plan to do the same with LAr1-ND and the cryogenic system.

5. Near Detector Building – Plan view at detector level Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept5 Wetland Delineation – June 2014 From S. Dixon, Sep 16,2014 Cryogenic System for detector Cryostat

6. Near Detector Building – Section view Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept6 From S. Dixon, Sep 16,2014 Cryogenic System for detector Cryostat

7. ParameterValue LAr purity in cryostat3 ms electron lifetime (100 ppt O2 equivalent) GAr Piston purge rate of rise1.2 m/hr Membrane cool-down rateFrom manufacturer (most likely < 10-15 K/hr) TPCs cool-down rate < 40 K/hr < 10 K/m (vertically) Mechanical load on TPC The LAr or the gas jet pressure shall not apply a mechanical load to the TPC greater than 200 Pascal. Nominal LAr purification flow rate (filling/ops)1 volume change/day All surfaces in the ullage during operations< 100 K Convective currents inside cryostat< 10 cm/s GAr purge within insulation 1 volume change/day of the open space between insulation panels Lifetime of the cryogenic system10 years (5 years of run + 5 years potential upgrade) 7 Portable system(s) lowered through the top in the SciBooNE hall, with quick connections to/from the cryostat. Scalable system(s) to be used for future larger detectors. Cryogenic and GAr/LAr purification systems to LBN design (where possible). Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept Cryogenic system requirements

8. Parameter (SciBooNE)Value Available footprint4.9 m x 5.1 m (To be verified) Available height11.5 m (two catwalks at intermediate levels) AccessibilityAccess from the top through the roof Lifting equipmentJib crane Connection to cryostat buildingUnderground tunnel 8Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept Space constraints See picture and drawing in next slide.

9. 9Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept SciBooNE 8,534 mm 3,048 mm 4,900 mm

10. ParameterValue LAr purification flow rate (filling/ops)1 volume change/day: 5.4 m 3 /hr = 24 gpm (129 m 3 ) Cooling power Cool-down: 14 kW (129 m 3 ) Operations: 2.2 kw (129 m 3 ) + TBD 10 Portable system(s) lowered through the top in the SciBooNE hall, with quick connections to/from the cryostat. Scalable system(s) to be used for future larger detectors. Cryogenic and GAr/LAr purification systems to LBN design (where possible). LN2 refrigeration based on LBN design is not cost effective. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept Cryogenic system current design parameters

11. LAr1-ND PFD of LAr systems (based on 35 ton) Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept11 This is the PFD of the LAr system of LAr1-ND based on the 35 ton concept (but with an external LAr pump and a system to spray clean LAr/GAr on the top to keep the ullage cold, ≤ 100 K). Assumption: 129 m 3 tank (base option).

12. This is the PFD of the LN2 system of LAr1-ND based on the 35 ton concept and CERN initial idea as presented by Johan Bremer on Jun 18, 2014. Assumption: 129 m 3 tank (base option). LAr1-ND PFD of LN2 system (based on 35 ton and Johan B) Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept12

13. 13 129 m 3 231 m 3 Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept Cryogenic LAr filter for LAr1-ND Conceptual (from Mark A.) Old option

14. Purification/Filtration system needs Gas purge/recirculation: GAr purification during initial cleaning. Filling: LAr purification. Operations: LAr + GAr boil off purification. GAr purge inside the insulation. LN2 tanker delivery to onsite LN2 dewar (10,000 gal available from D0): –Five (5) year usage based on estimated heat leak. LN2 Refrigerator based on LBN cycle NOT cost effective: –Estimated Cost of LN2 plant (Design, Procure, Install). –Power + GN2 costs. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept14

15. Cryogenic system capabilities – 1 To purify the LAr (filling and operations). To re-condense and purify the boil off gas. –LAr condenser and LN2 phase separator. –LAr circulation pump to send LAr to purification system To handle the LAr/GAr and LN2/GN2 flows: Initial cleaning  GAr purging and venting, GAr recirculation and purification. Ops  cool down, LAr filling, GAr boil off purification and re-condensation, LAr purification, LAr return to the tank. Make-up GAr. To maintain the top of the cryostat at ≤ 100 K. To monitor and control internal and external pressure: Pressure Control / Vacuum Protection PSV, VSV, Auto/Manual venting. To handle the GAr purge inside the insulation. Instrumentation and diagnostics: T and P sensors, flow meters, liquid level sensors, etc., analytical instruments to measure the contamination, in-line Purity Monitors (??), etc. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept15

16. Cryogenic system capabilities – 2 To sample GAr from the ullage and measure the concentration of contaminants. Control system. Flexibility: new features may be tested (cold roof, LAr external pump). To the extent possible, it is desired to have a flexible system where we can turn on/off the various features for comparison. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept16

17. Current list of penetrations through the top of the cryostat Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept17 Liquid level probe(s). LAr Out (to LAr pump through the side of the tank) LAr In (from pump discharge through purification system) Cool-down ports (depending on cool down method) GAr purge inlet GAr purge outlet GAr to condenser and vent valves Low P make-up GAr PSV VSV LAr cool-down T sensors T sensors Feedthrough Miscellaneous Feedthrough (LED lights, etc.) TPC Signal Feedthroughs (warm or cold ??) TPC HV feedthroughs (on center of cryostat) Photon detectors Calibration(s) Purity Monitor(s)? Glass window view port ?? Sampling ports LN2/GN2 heat exchanger ports Instrumentation & Diagnostics ?? Spare ports

18. Outstanding issues Portability/Scalability: studies on portability and how to design a portable/scalable system that can serve present and future generation detectors of any size. Studies on LN2 system design to be common (to the extent possible) to T600 (FD). Will be different than that of larger systems because of cost of LN2 refrigeration. Studies on how to keep all surfaces at a Temperature lower than 100 K. Studies on how to minimize noise in the vicinity of the wires (may also be coming from piping layout). LAr Pump (Outside): –Need to see how to isolate the pump electrically and mechanically from the TPC. Issues with electronic noise and microphonics. –Check grounding scheme. Ability to make modifications after run for 5 years –Access the tank. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept18

19. Design choices Which LAr filtration system ?? –Molecular sieve + Copper beds. –ICARUS style. Which LAr condenser ?? –Ar in tube and LN2 in shell –Ar in shell and LN2 in tube Which interface with cryostat ?? –Bayonet fittings. –Flanged connections. –Where is the boundary. Process controls strategy. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept19

20. Summary Preliminary thinking has been done on the layout of LAr1-ND cryogenic system for the base design (129 m 3 cryostat). A larger cryostat (231 m 3 ) was analyzed and discarded for cost considerations. The 168 m 3 version is a recent proposal and has not been analyzed yet from the cryogenic system standpoint. The purification flow rate and cooling power will slightly increase. Cryogenically the system ‘feels like’ the 35 ton system at Fermilab’s PC-4 but placed in separate facility. The requirements for the cryogenic system have been developed and are being finalized. LAr cryogenic system is thought to be a scaled-up version of that of 35 ton/LAPD. Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept20

21. Closing remark Fundamentally there are no foreseen issues related to increasing the cryostat size. There are increased costs for the cryogenic system (as well as the cryostat). They will scale with heat leak and the purification flow rate (and the cryostat surface). The design issues which is key: 1) How do we keep the surfaces of the ullage at T ≤ 100 K ? Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept21

22. Thanks! David Montanari Neutrino Cryogenics Requirements Meeting 24 September 2014

23. Backup Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept23

24. Current schedule The goal is to have the detector ready for commissioning in the fall of 2017 and to take beam data in Apr 2018. From the proposal submitted to the PAC in Jul 2014: Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept24 MilestoneDate Cryogenic plant proposal submitted for peer reviewMar 2015 LAr1-ND technical proposal submitted for peer reviewMar 2015 Cryogenics procurement plans released and activeSep 2015 Start cryogenic plant commissioningAug 2017 Start detectors cooling and commissioningNov 2017 Start data taking with beamApr 2018

25. 25Sep 24, 2014David Montanari | LAr1-ND Cryogenics Concept LN2 refrigeration conceptual (From Mark A.)