LBNE 35 ton prototype Phase 1 summary

1. LBNE 35 ton prototypePhase 1 summary Terry Tope Fermi National Accelerator Laboratory tope@fnal.gov All Experimenters’ Meeting – Fermilab – May 19, 2014

2. Background and Phase 1 Goals • LBNE wants to build a 10 kton Fiducial Mass Liquid Argon detector (two 5/9.3 kton FM/TM for a total of 19.8 kton ). • Membrane cryostat technology with passive insulation (Polyurethane foam). • We have built the LBNE 35 ton prototype (the first and only membrane cryostat for scientific purpose and available to scientists) with the Phase 1 goals of: • demonstrating the contractual business model with membrane cryostat supplier for the design and construction of a membrane cryostat  DONE. • demonstrating the membrane cryostat technology (thermal performance, feasibility for LAr, leak tightness)  DONE. • demonstrating that we can achieve the purity requirements in a membrane cryostat W/O evacuation  DONE. • equivalent O2 contamination 229 ppt, -> 1.4ms e- lifetime • from 9 to 1 Signal/Noise Requirement for minimum ionizing particle at a 3.48m drift distance and 500V/cm drift field. • achieving and maintaining purity requirements during filling, purification and maintenance mode  DONE. LBNE35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

3. Tank Interior Purity monitors (drift chambers) Liquid argon pumps Cool-down liquid sprayers 4 meters Argon purge distribution 2.7 meters LBNE35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

4. Room Temperature Argon Gas Purification “Dry Air” Piston Purge Recirculation ~32hrs N2 not removed by Filters H20, limited by outgassing Gas vented to atmosphere ~7days Plot by Alan Hahn LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

5. Liquid Argon Cryogenic Purification 12/18--Initial Fill (70%) 12/20—Pump “A” Starts Various Studies 2/7—Turn off Pumping 1/6—Top off LAr (100%) 12/30—Switch to Pump “B” 1/31—Switch Back to Pump “A” 2/13—Begin Pump out of LAr sent to MicroBooNE Lifetime (s) 100 ppt O2equiv Bottom Long PrM2 Top Short PrM4 LBNE e- lifetime requirement First e- lifetime measured, 460us, 41 hr after start of pumping Plot by Alan Hahn 2 filtration volume changes per day LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

6. Phase 2 Goals – Operation Winter 2014 • Build a complete functional reduced-scale sized TPC with Photon Detectors inside the 35-ton cryostat. • TPC components will closely resemble the full size counterparts. • Anode Plane Assemblies (APA) will incorporate functional photon detectors • Goals of this prototype TPC • Validate the design of nearly all Detector components (at a small scale); testing the integrity of all components and their interconnects in LAr. • Study the performance of the wire wrapping readout scheme, and the impact of the gaps between APA modules. • Study the electronics noise contribution from potential sources: acoustic, pump, flow driven wire or field cage motion, high voltage ripple coupling, coupling between digital and analog circuits, etc. LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

7. LBNE Style TPC in 35T Cryostat Cosmic Ray Counters (CRCs) 20 cm short drift region CRCs ~2m drift region CRCs Photon Detectors (8 total) in 4 APAs Cathode Plane Cathode Plane Field Cage not shown J. Fowler LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab