Akimov, DAn, PAwe, CBarbeau, PSBecker, BBelov, VBernardi, IBlackston, MABolozdynya, ACabrera-Palmer, BChernyak, DConley, EDaughhetee, JDay, EDetwiler, JDing, KDurand, MREfremenko, YElliott, SRFabris, LFebbraro, MGallo Rosso, AGalindo-Uribarri, AGreen, MPHeath, MRHedges, SHoang, DHughes, MJohnson, TKhromov, AKonovalov, AKoros, JKozlova, EKumpan, ALi, LLink, JMLiu, JMann, KMarkoff, DMMastroberti, JMueller, PENewby, JParno, DSPenttila, SIPershey, DRapp, RRay, HRaybern, JRazuvaeva, OReyna, DRich, GCRoss, JRudik, DRunge, JSalvat, DJSalyapongse, AMScholberg, KShakirov, ASimakov, GSinev, GSnow, WMSosnovstsev, VSuh, BTayloe, RTellez-Giron-Flores, KTolstukhin, IUjah, EVanderwerp, JVarner, RLVirtue, CJVisser, GWard, EMWiseman, CWongjirad, TYen, YRYoo, JYu, CHZettlemoyer, J2021-11-172021-11-172021-08-011748-02211748-0221https://hdl.handle.net/10161/23992We report on the technical design and expected performance of a 592 kg heavy-water-Cherenkov detector to measure the absolute neutrino flux from the pion-decay-at-rest neutrino source at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The detector will be located roughly 20 m from the SNS target and will measure the neutrino flux with better than 5% statistical uncertainty in 2 years. This heavy-water detector will serve as the first module of a two-module detector system to ultimately measure the neutrino flux to 2-3% at both the First Target Station and the planned Second Target Station of the SNS. This detector will significantly reduce a dominant systematic uncertainty for neutrino cross-section measurements at the SNS, increasing the sensitivity of searches for new physics.Membrane-coveredGas emissionBacterial communityAerobic compostingCherenkov and transition radiationCherenkov detectorsNeutrino detectorsJournal article2021-11-17