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

2. 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 O 2 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. 2 Background and Phase 1 Goals LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

3. 3 Tank Interior LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab Liquid argon pumps Purity monitors (drift chambers) 2.7 meters 4 meters Cool-down liquid sprayers Argon purge distribution

4. LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab 4 Gas vented to atmosphere H 2 0, limited by outgassing N 2 not removed by Filters ~32hrs ~7days Piston Purge Recirculation Room Temperature Argon Gas Purification “Dry Air” Plot by Alan Hahn

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

6. 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. 6 Phase 2 Goals – Operation Winter 2014 LBNE 35 ton prototype – All Experimenters’ Meeting – May 19, 2014 – Fermilab

7. 7 LBNE Style TPC in 35T Cryostat ~2m drift region 20 cm short drift region Photon Detectors (8 total) in 4 APAs J. Fowler Cosmic Ray Counters (CRCs) Field Cage not shown Cathode Plane CRCs