Workshop 5 minutes by Peter Denton SK/HK-Gd: Yasuhiro Nakajima 1. Gd loaded into SK 0.02% this year (50% neutron capture), final goal of 0.2% (90% neutron capture). 2. Physics goals: Primary: DSNB. Secondary: pointing for galactic SN, proton decay, nu/nubar discrimination, reactor. 3. Successfully observed neutron capture on Gd. Consistent with loading plan. 4. DSNB backgrounds: Li9, atmospheric NC 5. Current limits within factor of 2 of optimistic DSNB models 6. HK pure water: search is limited to E>16 MeV due to spallation. HK is shallower than SK (less overburden). 7. HK-Gd: reduce backgrounds, measure the DSNB spectrum with 100s events, study the SN rate to z~1. 8. Gd can separate nu/nubar and improve energy reconstruction. This will improve cpv, mass ordering, theta23, and Dmsq32 with LBL and atmospheric. 9. Things to check: Water leaks. Gd purity. Soak test of components. Optical properties. Radio-impurity. Event rates. Background reductions. Event reductions. First three are confirmed, rest are ongoing. Soak test is ongoing for HK. 10. Dedicated water purification for SK-Gd, 120 m^3/hr. Tests are just starting. 11. Radio impurity affects the important up turn region of the solar neutrino spectrum. 12. Have a NCQE measurement from beam to cross-callibrate for atmospheric to differentiate from DSNB. Still stat limited. 13. Neutron multiplicity at GeV energies (T2K) has a slight disagreement with MC. Maury: how do you choose Gd concentration? Yasuhiro: budget. Optical, radio quality. Peter: uncertainty on Gd cross section efficiency? Yasuhiro: Gd cross section uncertainty. Callibration source. Mark: explain the numbers on slide 11. Yasuhiro: nubar ID in atmospheric improves NuSTORM: Kenneth Long 1. nuSTORM is an entry level nu fact. Proton on target. Select pions. Transport to muon storage ring in race track configuration. 2. Goals: % level cross sections, ideally double differential over different materials. Allows for good high energy nu_e cross sections. Precise beam allows for good BSN constraints such as steriles. 3. Think can get normalization to <1%. 4. Provides a test bed for more muon collider physics. 5. Feasibility study of nuSTORM at CERN. Have a location in mind. ND hall at 50m, FD is farther. 6. Estimates for 3.8 GeV stored muon beam. 7. Enough precision such that LSND/MiniBooNE region can be excluded at 10sig. 8. CCQE nu_e measurement at GeV energies 9. Positive cross talk with Enubet 10. Feasibility study to appear very soon. 11. European strategy: have a suitable location. 12. Challenges: acceptance of storage ring needs to be large. Need a detailed evaluation of proton beam extraction. 13. European strategy output: bright muon beams mentioned as well as nu cross section measurements for DUNE/HK. 14. The muon is a fundamental particle. 15. Can build a large muon collider which has many benefits for HE physics. Peter Shanahan: what's the newest it could operate? Ken: break into tunnels no earlier than 2030 due to LHC schedule. Then at Peter: Quantitative improvement of DUNE/HK physics with nuSTORM? Ken: In progress. Peter: Target materials? Ken: Nothing is excluded. Water, Ar, 2H, ... Mark: Progression in muon storage ring? g-2 to nuSTORM is how big? What is the Livingston plot? Ken: muon accelerator staging facility study.