Latest Oscillation Results from NOvA Diana Patricia Mendez - PowerPoint PPT Presentation

Latest Oscillation Results from NOvA Diana Patricia Mendez University of Sussex on behalf of the NOvA Collaboration � 1

Neutrino oscillations ν e ν 1 θ 12 , θ 13 , θ 23 Mixing angles ν μ ν 2 = U PMNS δ CP CP phase ν 3 ν τ m 2 ν 2 ν 3 ν e ν µ ν τ ν µ ν τ Δ m 2 21 ν 1 ν e µ τ Δ m 2 32 Mass squared ν 2 ν e ν µ ν τ Δ m 2 21 , Δ m 2 Δ m 2 difference 32 32 Δ m 2 21 ν 1 ν µ ν τ ν 3 ν e µ τ Normal Inverted Hierarchy Hierarchy Moriond EW 2019 Diana Mendez � 2

Muon neutrino disappearance Δ m 2 32 L Prediction P ( ν μ → ν μ ) ≃ 1 − sin 2 (2 θ 23 )sin 2 ( ) No oscillation 80 4 E Events / 0.1 GeV 60 40 20 NOvA Simulation 1 Oscillation/No oscillation Ratio 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 Reconstructed Neutrino Energy (GeV) Moriond EW 2019 Diana Mendez � 3

Muon neutrino disappearance Δ m 2 32 L Prediction P ( ν μ → ν μ ) ≃ 1 − sin 2 (2 θ 23 )sin 2 ( ) No oscillation 80 4 E Events / 0.1 GeV Amplitude 60 40 20 NOvA Simulation 1 Oscillation/No oscillation Ratio 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 Reconstructed Neutrino Energy (GeV) Moriond EW 2019 Diana Mendez � 4

Muon neutrino disappearance Δ m 2 32 L Prediction P ( ν μ → ν μ ) ≃ 1 − sin 2 (2 θ 23 )sin 2 ( ) No oscillation 80 4 E Events / 0.1 GeV Frequency 60 40 20 NOvA Simulation 1 Oscillation/No oscillation Ratio 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 Reconstructed Neutrino Energy (GeV) Moriond EW 2019 Diana Mendez � 5

Muon neutrino disappearance Δ m 2 32 L Prediction P ( ν μ → ν μ ) ≃ 1 − sin 2 (2 θ 23 )sin 2 ( ) No oscillation 80 4 E Events / 0.1 GeV 60 θ 23 < π /4 40 Lower octant 20 θ 23 = π /4 Maximal mixing NOvA Simulation 1 Oscillation/No oscillation Ratio 0.8 θ 23 > π /4 0.6 Upper octant 0.4 0.2 0 0 1 2 3 4 5 Reconstructed Neutrino Energy (GeV) Moriond EW 2019 Diana Mendez � 6

Electron neutrino appearance No matter effects NOvA: L=810 km, E=2.0 GeV 8 Neutrino-antineutrino No difference in vacuum 6 % e ν 4 → µ ν P 2 0 0 2 4 6 8 P % ν → ν µ e Moriond EW 2019 Diana Mendez � 7

Electron neutrino appearance NOvA: L=810 km, E=2.0 GeV 8 Neutrino-antineutrino Opposite effects 6 % δ CP CP phase e ν 4 → µ ν P 2 =0 = /2 δ δ π = =3 /2 δ π δ π 0 0 2 4 6 8 P % ν → ν µ e Moriond EW 2019 Diana Mendez � 8

Electron neutrino appearance NOvA: L=810 km, E=2.0 GeV NOvA: L=810 km, E=2.0 GeV 8 Neutrino-antineutrino Inverted Hierarchy Opposite effects 6 % δ CP CP phase e ν 4 → NH, IH Hierarchy µ ν P 2 =0 = /2 δ δ π Normal Hierarchy = =3 /2 δ π δ π 0 0 2 4 6 8 P % ν → ν µ e Moriond EW 2019 Diana Mendez � 9

Electron neutrino appearance NOvA: L=810 km, E=2.0 GeV NOvA: L=810 km, E=2.0 GeV 8 Neutrino-antineutrino Inverted Hierarchy Opposite effects 6 % Upper δ CP CP phase octant e ν 4 → NH, IH Hierarchy µ ν P Lower 2 octant Similar effects =0 = /2 δ δ π Normal Hierarchy = =3 /2 δ π δ π θ 23 Symmetry 0 0 2 4 6 8 P % ν → ν µ e Moriond EW 2019 Diana Mendez � 10

The NOvA Experiment NuMI Off-axis Electron Neutrino Appearance Neutrino oscillation experiment • and disapperance ν μ ν μ ¯ • and appearance ν e ν e ¯ Far Detector Two detectors separated by 810 km MN • Near detector (underground): Beam WI composition, unoscillated flux MI • Far detector (surface): Oscillated spectra NOvA Preliminary Near Detector POT / 0.1 GeV Data 200 Predicted Events IL 1- σ syst. range Wrong Sign CC ν µ Total Background Area Normalised 150 Neutrino beam Neutrino (antineutrino) 20 10 × 100 source: Fermilab’s NuMI Events / 8.03 • 14 mrad off-axis beam 50 • Narrow energy spectrum 3 10 0 1 2 3 4 5 Reconstructed Neutrino Energy (GeV) Moriond EW 2019 Diana Mendez � 11

The NOvA Detectors 60 m Far Detector 15.6 m 14 kton 896 layers Near Detector 0.3 kton 214 layers 16 m 4.1 m y Beam 3.9 x 6.6 cm direction z x Moriond EW 2019 Diana Mendez � 12

Neutrino Beam Focusing Horns Target 2 m π -(+) ν µ ( ν µ ) 120 GeV ν µ ( ν µ ) π +(-) p + from MI NuMI: Neutrinos at the Main Injector (Fermilab) Most powerful beam in the World. Constantly operating at ~725 kW Moriond EW 2019 Diana Mendez � 13

New for 2018 analysis • First antineutrino data: Total analysis exposure 6.90x10 20 (antineutrino) + 8.85x10 20 (neutrino) POT • Updated particle classifier • Neutron uncertainty • Cross section ¯ ν ν Moriond EW 2019 Diana Mendez � 14

Event topology ν μ CC p ν μ μ Long straight track ν e CC p ν e e Short wide fuzzy shower NC π γ π 0 ν p γ 1m Gap between vertex and shower 1m 10 2 3 10 10 q (ADC) Moriond EW 2019 Diana Mendez � 15

Classifier CVN Algorithm based on CNNs to classify interactions Treats events as images to extracts features Multilayer classifier used between analyses New • Simpler architecture • Updated simulation • Separate training for antineutrino and neutrino beams A. Aurisano et. al, JINST 11 P0001 (2016) Moriond EW 2019 Diana Mendez � 16

Systematic uncertainties NOvA Preliminary NOvA Preliminary Detector Calibration Near-Far Differences Neutrino Cross Sections Detector Calibration Muon Energy Scale Neutrino Cross Sections Neutron Uncertainty Detector Response Detector Response Normalization Normalization Muon Energy Scale Near-Far Differences Beam Flux Beam Flux Neutron Uncertainty Systematic Uncertainty Systematic Uncertainty Statistical Uncertainty Statistical Uncertainty 0.05 0 0.05 0.5 0 0.5 − − -3 2 2 Uncertainty in / δ π Uncertainty in m ( 10 eV ) Δ × CP 32 NOvA Preliminary Largest New Neutron Uncertainty • Detector • Neutron Detector Calibration Calibration uncertainty Neutrino Cross Sections • Neutrino cross Limitations Muon Energy Scale sections • Statistics Normalization Detector Response Near-Far Differences • Data collection up to 2024 Beam Flux • Test beam program will improve Systematic Uncertainty calibration and detector response Statistical Uncertainty 20 0 20 − -3 2 Uncertainty in sin ( 10 ) θ × 23 Moriond EW 2019 Diana Mendez � 17

ν μ + ¯ ν μ Disappearance 4000 4500 5000 5500 6000 800 600 x (cm) 400 200 y (cm) 0 − 200 4000 4500 5000 5500 6000 z (cm) NOvA - FNAL E929 hits hits 2 10 2 10 Run: 23630 / 39 10 10 Event: 240802 / -- 1 1 UTC Mon Jul 25, 2016 218 220 222 224 226 228 2 3 10 10 10 04:23:7.211474672 t ( sec) q (ADC) µ � 18