DUNE as the Next-Generation Solar Neutrino Experiment Shirley Li Collaborators: Francesco Capozzi, Guanying Zhu, John Beacom NUFACT, August 2018
Why haven’t we resolved this? Outline Data from SK 2016 DUNE comes to rescue! What is this? Why haven’t we resolved this? Shirley Li (SLAC) 2/28
Why haven’t we resolved this? Outline Data from SK 2016 DUNE comes to rescue! What is this? Why haven’t we resolved this? Shirley Li (SLAC) 3/28
Solar neutrino spectra 0.1 MeV 1 MeV 10 MeV Borexino 2014 8B: used for oscillation study hep: haven’t been detected Shirley Li (SLAC) 4/28
Solar neutrino oscillation The survival probability Vacuum oscillation 1− 1 2 sin 2 2 𝜃 12 Matter effect sin 2 𝜃 12 Borexino 2014 Good agreement? Shirley Li (SLAC) 5/28
Oscillation phenomena Two matter-induced effects Upturn Day-night effect Vissani 2017 Both effects depend on neutrino energy Shirley Li (SLAC) 6/28
Current status Solar & reactor tension Reactor: vacuum oscillation Data from SK 2016 Reactor: vacuum oscillation Solar: matter effect Capozzi et al, in prep Tension driven by day-night effect Shirley Li (SLAC) 7/28
New physics? Maltoni & Smirnov, 2015 Shirley Li (SLAC) 8/28
Why haven’t we resolved this? Outline Data from SK 2016 DUNE comes to rescue! What is this? Why haven’t we resolved this? Shirley Li (SLAC) 9/28
𝜙 𝜈 𝑒 / 𝜙 𝜈 as a function of neutrino energy What we want to measure 𝜙 𝜈 𝑒 / 𝜙 𝜈 as a function of neutrino energy Upturn Day-night effect Vissani 2017 Shirley Li (SLAC) 10/28
SNO: 1999 -- 2006 Both NC and CC channel 𝜈 𝑥 +𝑑→ 𝜈 𝑥 +𝑝+𝑛 𝜈 𝑒 +𝑑→𝑒+𝑝+𝑝 sno.phy.queensu.ca 𝜈 𝑥 +𝑑→ 𝜈 𝑥 +𝑝+𝑛 𝜈 𝑒 +𝑑→𝑒+𝑝+𝑝 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 Provides 8B 𝜈 flux: 4% Shirley Li (SLAC) 11/28
SNO: 1999 -- 2006 Both NC and CC channel Provides 8B 𝜈 flux: 4% 12/28 sno.phy.queensu.ca Provides 8B 𝜈 flux: 4% Shirley Li (SLAC) 12/28
ES channel only: 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 Super-K: 1996 -- present ES channel only: 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 𝜈 𝑒 𝑒 𝜈 𝑒, 𝜇, 𝜏 𝜈 𝑒, 𝜇, 𝜏 𝑊 𝑍 𝑒 𝜈 𝑒 𝑒 𝑒 Shirley Li (SLAC) 13/28
Super-K: 1996 -- present ES channel only: 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 Li 2017 𝑓 𝑒 +1/6( 𝑓 𝜇 + 𝑓 𝜏 ) sin 2 𝜃 limited by SNO flux Shirley Li (SLAC) 14/28
Super-K: 1996 -- present ES channel only: 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 Li 2017 Neutrino energy dependence washed out Smear 𝛿 𝑚 2 Shirley Li (SLAC) 15/28
Why haven’t we resolved this? Outline Data from SK 2016 DUNE comes to rescue! What is this? Why haven’t we resolved this? Shirley Li (SLAC) 16/28
4 10-kton liquid argon TPC module DUNE 4 10-kton liquid argon TPC module Trigger 𝑇 𝑒 >5 MeV Energy resolution 7% Angular resolution 25∘ sciencemag.org Shirley Li (SLAC) 17/28
Unique advantage of DUNE CC channel: 𝜈 𝑒 +Ar→𝑒+ K ∗ 𝜈 𝑒 𝑒 𝑊 Ar K* 𝛾 Shirley Li (SLAC) 18/28
Unique advantage of DUNE CC channel: 𝜈 𝑒 +Ar→𝑒+ K ∗ Combine with: 𝜈 𝑥 +𝑒→ 𝜈 𝑥 +𝑒 Improve on sin 2 𝜃 Capozzi et al, in prep Shirley Li (SLAC) 19/28
Unique advantage of DUNE CC channel: 𝜈 𝑒 +Ar→𝑒+ K ∗ 𝐸 𝑒 = 𝐸 𝜈 −𝑄−ΔE Improve on 𝛿 𝑚 2 Shirley Li (SLAC) 20/28
Event rate in DUNE 100 kton-year exposure 21/28 Capozzi et al, in prep Shirley Li (SLAC) 21/28
In addition, 8B flux 2.5%, hep flux 10% Results Capozzi et al, in prep In addition, 8B flux 2.5%, hep flux 10% Shirley Li (SLAC) 22/28
Solar neutrino in DUNE Program Shirley Li (SLAC) 23/28
Trigger Shirley Li (SLAC) 24/28
Backgrounds Three options: ~ 40 cm of water/plastic shielding Capozzi et al, in prep Three options: ~ 40 cm of water/plastic shielding Double the exposure Separating gamma from electron Shirley Li (SLAC) 25/28
Threshold Depends on reconstruction & background level Capozzi et al, in prep Can be compensated by larger exposure Shirley Li (SLAC) 26/28
Current uncertainty: a few % Cross section Current uncertainty: a few % Capozzi et al, in prep Shirley Li (SLAC) 27/28
Conclusions Shirley Li (SLAC) 28/28
Back up
Measured metallicities Shirley Li (SLAC) 24/24
Cross section Shirley Li (SLAC) 24/24
Cross section Shirley Li (SLAC) 24/24
Cross section Shirley Li (SLAC) 24/24
Mass square sensitivity Shirley Li (SLAC) 24/24