1.         PMT Liquid Scintillator Gadolinium Loaded Lead Veto Hadronic Shower Liberated Neutrons High Energy Neutron No Veto, Small Prompt Energy Deposit   Capture on Gd, Gammas (spread over 40 μs) 40 cm 50 cm 200 cm One of four in depth

2.         PMT Liquid Scintillator Gadolinium Loaded Lead Veto Hadronic Shower Liberated Neutrons   Capture on Gd, Gammas (spread over 30 μs)             Muon Veto, Large Energy Deposit High Energy Neutron No Veto, Small Prompt Energy Deposit

3. time40 μs PMT Signal Neutron Event Muon Event dE/dx Shower Initiation, backsplash, proton recoil Neutron captures

4. Neutron Multiplicity Counter 440 kg Gd/Liquid Scintillator in box 200 cm 50 cm PMT/Base 35 cm PMT/Base Winston Cone Mirror

5. 50 cm 200 cm Top/Bottom/Sides: ¼” thick Acrylic or PVC; if opaque line with Chemflour white plastic (see MACRO paper) Ends…clear… Acrylic, mirrors inside or out (?) Bottom… need strongback (?), levelling feet… want top scint surface to not touch the box top Scintillator Box

6. PMT Amp Waveform Digitizer VME Discrim Neutron Detectors OR First Pulse Stretch (30 μs) Gated Scaler ≥n Trigger DAQ Computer Data Acquisition Veto Detectors History Buffer

7. Organization 1.Simulation / Physics Design (CWRU) 2.Neutron Detectors 1.Design (UCSB) 2.Prototype (UCSB) 3.Fabrication (UCSB) 4.Testing (UCSB) 5.Soudan Commissioning (CWRU/UCSB) 3.Veto Detectors (UCSB(?)… FNAL?) 4.Calibration System 5.Electronics 6.DAQ 7.Data Analysis