KOPIO Catcher System RSVP Preliminary Baseline Review Brookhaven National Laboratory April 6, 2005 Tadashi Nomura (Kyoto U.)

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review2 Scope of Catcher System TASK –Detect photons passing through the beam hole –Be insensitive to a vast amount of neutrals in the beam In order to avoid false vetoes by beam neutrons and surviving K L s Required photon efficiency –99% for photons with E>300MeV From the spectrum of photons into the catcher after kinematical cuts (dominated by K  2 odd pairing events) Sensitivity to neutrons –<0.3% for neutrons with Ekin=800MeV SCOPE

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review3 Concept of Catcher System SOLUTION –Utilize Cherenkov radiation Lead and aerogel tile sandwich counter inside the beam named “Aerogel Catcher” Lead and acrylic slab sandwich counter near the beam named “Guard Counter ” aerogel mirror Cerenkov light lead sheet 5inch PMT Aerogel Catcher Module Winston-type funnel Guard Counter Concept SCOPE

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review4 Principle of Aerogel Catcher AEROGEL CATCHER Lead and aerogel tile counter Avoid detection of slow particles from neutron interactions Distributed arrangement Coincidence along the beam helps us catch forward  only aerogel flat mirror Cerenkov light lead sheet 5inch PMT Module funnel  red: e + /e -, blue: photon Photon’s EM shower in the module array AEROGEL CATCHER

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review5 Principle of Guard Counter GUARD COUNTER Lead and acrylic slab counter Slow particle doesn’t emit Cherenkov light Utilize the total reflection angle in light transportation Cherenkov lights from slow particles don’t fulfill the total reflection condition PhotonNeutron GUARD COUNTER

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review6 Aerogel Counter (WBS ) In-beam Pb-Aerogel Sandwich –Module size: 30cm x 30cm –Pb converter: 2mm per layer –Number of modules: in horizontal with beam divergence 25 layers along beam (8.3 X 0 in total) –Z gap between layers: 35cm –Coincidence condition >= 4 p.e. in 1 st layer (A) >= 2 p.e. in 2 nd layer (B) Top view 12m downstream of main detector Beam envelope AEROGEL CATCHER Module

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review7 Guard Counter (WBS ) Pb-Acrylic sandwich to cover the halo region Many soft neutrons around the beam Lead & acrylic slab sandwich –Size: 15cm x 15cm –8 layers of 2mm Pb + 10mm acrylic –Read by 5 inch PMT –3 modules along the beam –Number of modules: 144 Side View Front View beam Module GUARD COUNTER

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review8 Expected Photon Efficiency EXPECTED PERFORMANCE Aerogel Catcher Efficiency Y position dependence 300MeV

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review9 Efficiencies for Other Neutrals EXPECTED PERFORMANCE Hit probability for Neutrons 800MeV Hit probability for KLs Dominated by decays in the Catcher

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review10 Proof of Principle Prototype 1 (2001-2) –1/4 size, flat mirror light yield Prototype 2 (2002-3) –1/4 size, parabolic mirror light yield response to proton (as substitute for neutron)  Check single layer eff. / two-layers’ coincidence  Good agreement with MC (with gas scintillation) PT2 PT1 PROOF OF PRINCIPLE

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review11 Cost Summary COST Catcher System covered by the contribution from Japan Japan-US fund Labor provided by graduate students

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review12 Costs of Key Components (1) Aerogel tile –WBS k$  Catalog price by Matsushita  Risk The price of new, transparent tiles (YI-50) not fixed yet COST

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review13 Costs of Key Components (2) 5 inch Photomultiplier –WBS for Aerogel Catcher 735 k$ –WBS for Guard Counter 252 k$  Catalog price with usual discount for mass production (quoted by Hamamatsu) COST

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review14 Costs of Key Components (3) Winston-type funnel –WBS k$  Unofficial quotation by Vendor (Yokohama Kikou Co.Ltd.) communication  Test Production Done in March COST

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review15 Schedule SCHEDULE

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review16 Schedule Summary Schedule and Milestones (2006/07 – 2009/07) –2006/07 – 2008/09 … Aerogel Counter (WBS ) 2008/06/30 Aerogel tile production completed 2007/09/27 Delivery of inch PMTs completed 2008/04/01 Winston-type funnel completed –2007/10 – 2008/09 … Guard Counter (WBS ) 2008/06/30 Delivery of 144 PMTs completed –2008/04 – 2009/01 … Front End Electronics (WBS ) 2009/01/30 WFD fabrication completed –2007/12 – 2008/12 … Shipping (WBS ) –2008/10 – 2009/04 … Installation (WBS ) 2009/04/30 Installation completed –2009/06 – 2009/07 … Commissioning (WBS ) SCHEDULE

April 6-8, 2005 Tadashi Nomura (Kyoto U.) RSVP Preliminary Baseline Review17 Cost Profile FY2005 FY k$1/6 of AC PMT FY k$ 829k$ 551k$ 5/6 of AC PMT Half of Aerogel/optical components FY k$ 655k$ 421k$ 245k$ Half of Aerogel/optical components Guard Counter Half of Front End Electronics FY k$ 188k$Half of FEE COST & SCHEDULE