Slide from Marco Martini) a New Concept to Measure, and Report Neutrino Cross Section Data, Now the Standard of the Community

1. MiniBooNE 2. Beam Observation of a Significant Excess of Electron-Like Events3. Detector 4. Oscillation in the MiniBooNE Short-Baseline Neutrino Experiment5. Discussion arXiv:1805.12028 outline 1. MiniBooNE neutrino experiment 2. Booster Neutrino Beamline (BNB) 3. MiniBooNE detector 4. Oscillation candidate search 5. Discussion

Teppei Katori for the MiniBooNE collaboration Queen Mary University of London HEP seminar, UCL, UK, June 14, 2018 13/06/18 1 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion 1. MiniBooNE neutrino experiment

2. Booster Neutrino Beamline (BNB)

3. MiniBooNE detector

4. Oscillation candidate search

5. Discussion

13/06/18 2 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion

13/06/18 3 PHYSICAL REVIEW LETTERS 120, 141802 (2018) signature of dark matter annihilation in the Sun [5,6]. 1. MiniBooNE Despite the importance of the KDAR neutrino, it has never MiniBooNE 2. Beam been isolated and identified. 3. Detector 86 m 4. Oscillation In the charged current (CC) interaction of a 236 MeV νμ background KDAR 12 − NuMI 5. Discussion (νμ C → μ X), the muon kinetic energy (Tμ) and closely beam decay pipe related neutrino-nucleus energy transfer (ω E − E ) horns ν μ target distributions are of particular interest for benchmarking¼ absorber neutrino interaction models and generators, which report widely varying predictions for kinematics at these tran- 5 m 675 m sition-region energies [7–14]. Traditionally, experiments 40 m are only sensitive, at best, to total visible hadronic energy FIG. 1. The NuMI beamline and various sources of neutrinos since invisible neutrons and model-dependent nucleon that reach MiniBooNE (dashed lines). The signal KDAR neu- removal energy corrections prevent the complete trinos (solid line) originate mainly from the absorber. reconstruction of energy transfer [16]. The measurements reported here, therefore, provide a unique look at muon kinematics and the relationship to neutrino energy in the antineutrino modes, since KDAR production from the few hundreds of MeV range, highly relevant for both absorber is not dependent on the polarization of the horns. elucidating the neutrino-nucleus interaction and performing However, the background νμ and ν¯μ event rate is predicted low energy precision oscillation measurements at short to be about 30% lower in the antineutrino mode. We use data taken in this configuration from 2009 2011, corre- [17–19] and long baselines [20]. – sponding to 2.62 × 1020 protons on the NuMI target. The MiniBooNE detector uses 445 tons (fiducial volume) PRL120(2018)141802 of mineral oil and 1280 photomultiplier tubes (PMTs), with The focus of this analysis is on reconstructing KDAR- an additional 240 PMTs instrumenting a veto region, to like low energy νμ CC events. A simple detector observ- identify neutrino events originating from the Booster able, PMThits5ns, defined as the number of PMT hits Neutrino Beamline (BNB) and Neutrinos at the Main multiplied by the fraction of light detected in the first 5 ns Injector (NuMI) neutrino sources. The experiment has after correcting for vertex position, is used to reconstruct Tμ reported numerous oscillation and cross section measure- in selected events featuring (1) an electron from muon ments and new physics searches since data taking began in decay, noting that about 7.8% of μ− capture on nuclei [26], 2002 [17]. For this analysis, we consider the charge and time (2) a lack of veto activity, and (3) a reconstructed distance data of PMT hits collected during the NuMI beam spill. NuMI between the end point of the primary track and the muon provides an intense source of KDAR neutrinos at MiniBooNE decay vertex of < 150 cm. This detector observable is in a somewhat indirect way. The 96 cm, 2.0 interaction length meant to isolate the muon via its characteristic prompt NuMI target allows about 1=6 of the primary NuMI protons Čerenkov light, as compared to the delayed scintillation- (120 GeV) to pass through to the beam absorber [21], 725 m only light (τ 18 ns) from the below-threshold hadronic ¼ downstream of the target and 86 m from the center of part of the interaction. According to the NUWRO neutrino MiniBooNE. The aluminum-core absorber, surrounded by event generator [12], only 14% of muons created in concrete and steel, is nominally meant to stop the remnant 236 MeV νμ CC events are expected to be produced with hadrons, electrons, muons, and gammas that reach the end of MiniBooNEenergy less than keep 39 MeV, providing the Čerenkov threshold for 13/06/18 4 the decay pipe. Interactions of primary protons with the highmuons impact in MiniBooNE results! mineral oil. KDAR-induced muons PRL118(2017)221803 absorber provide about 84% of the total KDAR neutrinos are expected to populate a “signal region,” defined as from NuMI that reach MiniBooNE. Predictions from FLUKA 0–120 PMThits5ns and representing Tμ in the range [22,23], MARS [24],andGEANT4 [25] for kaon production at 0–115 MeV. Because of the kinematics of 236 MeV νμ the absorber vary significantly, from 0.06–0.12 KDAR CC events, no signal is expected elsewhere, which is con- νμ/proton on target. The background to the KDAR signal, sidered the “background-only region” (>120 PMThits5ns). νμ and ν¯μ CC events which produce a muon in the 0–115 MeV Although the signal muon energy range considered for this range, originates mainly from pion and kaon decay in flight measurement is lower than past MiniBooNE cross section near the target station and in the upstream-most decay pipe. analyses featuring νμ=ν¯μ [27–33], the energy and timing The non-KDAR νμ and ν¯μ flux from the absorber, dominated distributions of MiniBooNE’s vast calibration sample of by decay-in-flight kaons (Kμ3 and Kμ2) with a comparatively 0–53 MeV electrons from muon decay provide a strong small charged pion component, is expected to contribute at benchmark for understanding the detector’s response to the few-percent level based on a GEANT4 simulation of the low energy muons in terms of both scintillation and beamline. Figure 1 shows a schematic of the NuMI beamline Čerenkov light. Further, a scintillator “calibration cube” in and its relationship to MiniBooNE. the MiniBooNE volume at a 31 cm depth, used to form a very The KDAR event rate at MiniBooNE is expected to be pure sample of tagged 95 4 MeV cosmic ray muons, similar in both NuMI’s low-energy neutrino and shows excellent agreement betweenÆ data and Monte Carlo

141802-2 LSND, PRD64(2002)112007 1. MiniBooNE � 2. Beam � � ⟶ � = ��2�� 1.27Δ� 3. Detector 1. LSND experiment 4. Oscillation � 5. Discussion LSND experiment at Los Alamos observed excess of anti-electron neutrino events in the anti-muon oscillation + n µ ¾¾¾¾®n e + p ® e + n neutrino beam. n + p ® d + g 87.9 ± 22.4 ± 6.0 (3.8.s) L/E~30m/30MeV~1 LSND signal

+ + p ®n µ + µ + + µ ® e +n e +n µ

13/06/18 5 LSND, PRD64(2002)112007 1. MiniBooNE 2. Beam 3. Detector 1. LSND experiment 4. Oscillation 5. Discussion

3 types of neutrino oscillations are found:

LSND neutrino oscillation: Dm2~1eV2 Atmospheric neutrino oscillation: Dm2~10-3eV2 Solar neutrino oscillation : Dm2~10-5eV2

But we cannot have so many Dm2!

2 2 2 Dm13 ≠ Dm12 + Dm23

ns nt nµ ne

LSND signal indicates 4th generation neutrino, but we know there is no additional flavor from Z-boson decay, so it must be sterile neutrino MiniBooNE is designed to have same L/E~500m/500MeV~1 to test LSND Dm2~1eV2

16/07/18 6 1. MiniBooNE � 2. Beam � � ⟶ � = ��2�� 1.27Δ� 3. Detector 1. MiniBooNE experiment 4. Oscillation � 5. Discussion Keep L/E same with LSND, while changing systematics, energy & event signature;

MiniBooNE is looking for the single isolated electron like events, which is the signature of ne events

oscillation − νµ    → νe + n → p + e oscillation p n e+ ν µ    → νe + → + FNAL Booster target and horn decay region absorber dirt detector

€ K+ p+ ??? Booster nµ ® ne

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos) MiniBooNE has; - higher energy (~500 MeV) than LSND (~30 MeV) - longer baseline (~500 m) than LSND (~30 m)

13/06/18 7 1. MiniBooNE 2. Beam 3. Detector 1. MiniBooNE is extremely influential! – Tools 4. Oscillation 5. Discussion

MiniBooNE: NIMA608(2009)206 fitQun: Flux systematic error: MiniBooNE: PRD79(2009)072002 Likelihood-based Cherenkov ring - Errors are derived directly from hadron production fitter, the main reconstruction data (spline fit), not any flux model. used by Super-Kamiokande - Event weighted with multiverse simulation to make (LSNDàMiniBooNEàSuperK). a smooth covariance matrix with taking account all correlations correctly.

Sanford-Wang fit error data error

Online remote shift: - <1 event per minute - Even ACNET became web interface after this! - Almost all neutrino experiments at Fermilab adapted online remote shift, including NOvA, MicroBooNE, MINERvA, etc

13/06/18 8 1. MiniBooNE 2. Beam 3. Detector 1. MiniBooNE is extremely influential! – Offsprings 4. Oscillation 5. Discussion

Argonne: Zelimir MSU: Kendall Djurcic (PD) Mahn (PhD) Lancaster: Jarek Nowak (PD) Fermilab: Chicago: Dave Yale: Bonnie Jen Raaf (PhD) Schmitz (PhD) Fleming (PD) Fernanda Garcia (PD) Zarko Pavlovic (PD) Royal Holloway: Chris Polly (PD) Jocelyn Monroe (PhD) Sam Zeller (PD) Columbia: Georgia Karagiorgi (PhD) Queen Mary: Teppei Katori (PhD) SLAC: Hiro Tanaka (PD) IHEP: Jun Stony Brook: Mike Cao (PD) Wilking (PhD) Imperial: Morgan Caltech: Ryan Wascko (PD) Patterson (PhD) Pittsburgh: Brian Batell (PD) IFIC: Michel NMSU: Robert Sorel (PhD) Cooper (PD) Virginia Tech: Jon Link (PD) Colorado: Eric Zimmerman (PD) LSU: Martin Florida: Heather Tzanov (PD) Ray (PD) UNAM: Alexis Aguilar Arevalo (PhD)

…and more are coming!

13/06/18 9 MiniBooNE: PRD81(2010)092005 1. MiniBooNE Martini et al,PRC80(2009)065501 2. Beam 3. Detector 1. MiniBooNE is extremely influential! – Cross Sections 4. Oscillation 5. Discussion

Flux-integrated differential cross section: (Slide from Marco Martini) A new concept to measure, and report neutrino cross section data, now the standard of the community.

Discovery of nucleon correlation in neutrino scattering: - Significant enhancement of cross section (10-30%) - modify lepton kinematics and final state hadrons - the hottest topic for T2K, MINERvA, MicroBooNE, etc Particle Data Group - Section 42, “Monte Carlo Neutrino Generators” (Hugh Gallagher, Yoshinari Hayato) - Section 50, “Neutrino Cross-Section Measurements” (Sam Zeller)

On going effort from MiniBooE initiative! The first textbook of neutrino interaction physics! “Foundation of Nuclear and Particle Physics” - Cambridge University Press (2017), ISBN:13/06/180521765110 10 - Authors: Donnelly, Formaggio, Holstein, Milner, Surrow 1. MiniBooNE 2. Beam 3. Detector 1. NuInt18 and nuS&DIS workshop, GSSI, Italy 4. Oscillation 5. Discussion NuInt18, Oct 15-19 GSSI (Italy) https://indico.cern.ch/event/703880/ Register now! - the biggest conference on neutrino interaction physics for oscillations

Neutrino Shallow and Deep-Inelastic scattering, Oct 11-13 GSSI (Italy) http://nustec.fnal.gov/nuSDIS18/ - a dedicated workshop for physics related to DUNE, NOvA, etc

13/06/18 11 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion 1. MiniBooNE neutrino experiment

2. Booster Neutrino Beamline (BNB)

3. MiniBooNE detector

4. Oscillation candidate search

5. Discussion

13/06/18 12 MiniBooNE, PRD79(2009)072002 1. MiniBooNE 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion

MiniBooNE extracts beam from the 8 GeV Booster FNAL Booster

Booster Target Hall

FNAL Booster target and horn decay region absorber dirt detector

K+ p+ ??? Booster nµ ® ne

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos)

13/06/18 13 MiniBooNE, PRD79(2009)072002 1. MiniBooNE 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion

MiniBooNE extracts beam from the 8 GeV Booster FNAL Booster

Booster Target Hall

FNAL Booster target and horn decay region absorber1.5ns dirt x82detector …... 19ns

K+ Beam bunch structure p+ ??? Booster nµ ® ne 1.6µs

primary beam secondary beam tertiary beam 20µs (trigger) (protons) (mesons) (neutrinos) Beam spill structure 13/06/18 14 MiniBooNE, PRD79(2009)072002 1. MiniBooNE 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion Magnetic focusing horn 8GeV protons are delivered to a 1.7 l Be target

within a magnetic horn (2.5 kV, 174 kA) that increases the flux by ´ 6

By switching the current direction, the horn can focus either positive (neutrino mode) or negative (antineutrino mode) mesons.

FNAL Booster target and horn decay region absorber dirt detector

p- p+

K+ p+ ??? Booster nµ ® ne p+ p-

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos)

13/06/18 15 MiniBooNE, PRD79(2009)072002 1. MiniBooNE HARP, Eur.Phys.J.C52(2007)29 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion

HARP experiment (CERN) Modeling of meson production is based on the measurement done by HARP collaboration. - Identical, but 5% l Beryllium target - 8.9 GeV/c proton beam momentum - >80% coverage for p+

FNAL Booster target and horn decay region absorber dirt detector

K+ p+ ??? Booster nµ ® ne

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos)

13/06/18 16 MiniBooNE, PRD79(2009)072002 1. MiniBooNE HARP, Eur.Phys.J.C52(2007)29 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion

HARP kinematic coverage FNAL Booster target and horn decay region absorber dirt detector

K+ p+ ??? Booster nµ ® ne

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos)

13/06/18 17 MiniBooNE, PRD79(2009)072002 1. MiniBooNE 2. Beam 3. Detector 2. Neutrino beam 4. Oscillation 5. Discussion Neutrino flux from simulation by GEANT4 p ® µ nµ

MiniBooNE is the ne (anti ne) appearance oscillation experiment, so we need to know the distribution of beam origin ne and anti ne (intrinsic ne) K® µ nµ neutrino mode antineutrino mode intrinsic ne 0.6% 0.6% contamination

intrinsic ne from µ decay 49% 55%

µ ® e nµ ne intrinsic ne from K decay 47% 41% others 4% 4% K® p e ne wrong sign fraction 6% 16% FNAL Booster target and horn decay region absorber dirt detector

K+ p+ ??? Booster nµ ® ne

primary beam secondary beam tertiary beam (protons) (mesons) (neutrinos) 18 13/06/18 Huang, Neutrino 2018 1. MiniBooNE 2. Beam 3. Detector 3. Data taking 4. Oscillation 5. Discussion

13/06/18 19 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion 1. MiniBooNE neutrino experiment

2. Booster Neutrino Beamline (BNB)

3. MiniBooNE detector

4. Oscillation candidate search

5. Discussion

13/06/18 20 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

The MiniBooNE Detector - 541 meters downstream of target - 12 meter diameter sphere (10 meter “fiducial” volume)

- Filled with 800 t of pure mineral oil (CH2) Booster (Fiducial volume: 450 t) - 1280 inner phototubes, - 240 veto phototubes

13/06/18 21 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

The MiniBooNE Detector - 541 meters downstream of target - 12 meter diameter sphere (10 meter “fiducial” volume)

- Filled with 800 t of pure mineral oil (CH2) (Fiducial volume: 450 t) - 1280 inner phototubes, - 240 veto phototubes

13/06/18 22 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

The MiniBooNE Detector - 541 meters downstream of target - 12 meter diameter sphere (10 meter “fiducial” volume)

- Filled with 800 t of pure mineral oil (CH2) (Fiducial volume: 450 t) - 1280 inner phototubes, - 240 veto phototubes

13/06/18 23 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

Times of hit-clusters (subevents) Beam spill (1.6µs) is clearly evident Beam and simple cuts eliminate cosmic Cosmic BG backgrounds

Neutrino Candidate Cuts <6 veto PMT hits Gets rid of muons

>200 tank PMT hits Gets rid of Michels

Only neutrinos are left!

13/06/18 24 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

Times of hit-clusters (subevents) Beam spill (1.6µs) is clearly evident Beam and simple cuts eliminate cosmic Michels backgrounds

Neutrino Candidate Cuts <6 veto PMT hits Gets rid of muons

>200 tank PMT hits Gets rid of Michels

Only neutrinos are left!

13/06/18 25 MiniBooNE,NIM.A599(2009)28 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 3. Events in the Detector 5. Discussion

Times of hit-clusters (subevents) Beam spill (1.6µs) is clearly evident Beam simple cuts eliminate cosmic Only backgrounds

Neutrino Candidate Cuts <6 veto PMT hits Gets rid of muons

>200 tank PMT hits Gets rid of Michels

Only neutrinos are left!

13/06/18 26 MiniBooNE collaboration, 3. Events in the Detector NIM.A599(2009)28 Muons - Long strait tracks à Sharp clear rings

Electrons - Multiple scattering - Radiative processes à Scattered fuzzy rings

Neutral pions - Decays to 2 photons à Double fuzzy rings

NC elastic scattering - No Cherenkov radiation

à13/06/18Isotropic scintillation hits 27 MiniBooNE collaboration, 3. Events in the Detector NIM.A599(2009)28 Muons - Long strait tracks à Sharp clear rings

Electrons - Multiple scattering - Radiative processes à Scattered fuzzy rings

Neutral pions - Decays to 2 photons à Double fuzzy rings

NC elastic scattering - No Cherenkov radiation

à13/06/18Isotropic scintillation hits 28 MiniBooNE collaboration, 3. Events in the Detector NIM.A599(2009)28 Muons - Long strait tracks à Sharp clear rings

Electrons - Multiple scattering - Radiative processes à Scattered fuzzy rings

Neutral pions - Decays to 2 photons à Double fuzzy rings

NC elastic scattering - No Cherenkov radiation

à13/06/18Isotropic scintillation hits 29 MiniBooNE collaboration, 3. Events in the Detector NIM.A599(2009)28 Muons - Long strait tracks à Sharp clear rings

Electrons - Multiple scattering - Radiative processes à Scattered fuzzy rings

Neutral pions - Decays to 2 photons à Double fuzzy rings

NC elastic scattering - No Cherenkov radiation

à13/06/18Isotropic scintillation hits 30 MiniBooNE: PRL100(2008)032301 1. MiniBooNE 2. Beam 3. Detector 3. QE kinematics based energy reconstruction 4. Oscillation 5. Discussion

Event reconstruction from Cherenkov ring profile for PID - scattering angle q and kinetic energy of charged lepton T are estimated

Charged Current Quasi-Elastic (CCQE) interaction The simplest and the most abundant interaction around ~1 GeV. Neutrino energy is reconstructed from the observed lepton kinematics “QE assumption” 1. assuming neutron at rest � � 2. assuming interaction is CCQE � + � ⟶ � + � (� + � ⟶ � + � ) � X T � µ µ � n -beam cosq �� − 0.5� � = n � − � + �� p CCQE is the most important channel of neutrino oscillation physics for MiniBooNE, T2K, microBoonE, SBND, etc (also important for NOvA, Hyper-Kamiokande, DUNE, etc)

13/06/18 31 1. MiniBooNE 2. Beam 3. Detector 3. Detector stability 4. Oscillation 5. Discussion Event rate look consistent from expectations - Antineutrino mode (factor 5 lower event rate) - factor ~2 lower flux - factor ~2-3 lower cross section - Dark matter mode (factor 50 lower event rate) MiniBooNE, PRL118(2017)221803 - factor ~40 lower flux

32 13/06/18 1. MiniBooNE 2. Beam 3. Detector 3. Detector stability 4. Oscillation 5. Discussion Old and new data agree within 2% over 8 years separation.

Michel electron spectrum peak 38

32 All Mean E (MeV) 30

26 01 04 12 05 01 08 12 09 01 12 12 13 01 16

0.05 0 -0.05 -0.1 -0.15 -0.2 -0.25 2% energy shift is applied to the new data set Fractional deviation from average 01 04 12 05 01 08 12 09 01 12 12 13 01 16

33 13/06/18 1. MiniBooNE 2. Beam 3. Detector 3. Detector stability 4. Oscillation 5. Discussion Old and new data agree within 2% over 8 years separation.

EnQE from nµCCQE sample po mass peak from NCpo sample

34 13/06/18 1. MiniBooNE 2. Beam 3. Detector 3. Data-Simulation comparison 4. Oscillation 5. Discussion Old and new data agree within 2% over 8 years separation. - Excellent agreements with MC. EnQE from nµCCQE sample po mass peak from NCpo sample

35 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion 1. MiniBooNE neutrino experiment

2. Booster Neutrino Beamline (BNB)

3. MiniBooNE detector

4. Oscillation candidate search

5. Discussion

13/06/18 36 1. MiniBooNE 2. Beam 3. Detector 4. Internal background constraints 4. Oscillation misID 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E intrinsic

37 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from -decay constraint 4. Oscillation ne µ 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

ne from µ decay is constrained from nµCCQE measurement

38 13/06/18 1. MiniBooNE 2. Beam measured 3. Detector 4. n from µ-decay constraint 4. Oscillation e 5. Discussion � ⟶ � + � � ⟶ � + �̅ + � All backgrounds are internally constrained

à intrinsic (beam ne) = flat guessed à misID (gamma) = accumulate at low E � ⟶ � + �̅ � ⟶ � + � + �̅

They are large background, but we have a good control of �&�̅ background by joint �&�(�̅ &�̅ ) fit for oscillation search.

En-Ep space (GeV) n E

p ® µ nµ

µ ® e nµ ne

Ep(GeV)

39 13/06/18 MiniBooNE, PRD84(2011)072005 1. MiniBooNE 2. Beam 3. Detector 4. Anti-neutrino mode flux tuning 4. Oscillation 5. Discussion

�̅ &�̅ flux are harder to predict due to larger wrong sign (�&�) background, and measured lepton kinematics and p+ production are used to tune flux à they consistently suggest we overestimate antineutrino flux around 20%

Michel electron counting is sensitive to � contamination in �̅ beam

40 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from -decay constraint 4. Oscillation ne µ 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

En-Ep (GeV) n space p ® µ nµ E

ne from µ decay is constrained from nµCCQE µ ® e nµ ne measurement Ep(GeV)

41 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from K+-decay constraint 4. Oscillation ne 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

ne from µ decay is constrained from nµCCQE measurement

ne from K decay is constrained from SciBooNE high energy nµ event measurement

42 13/06/18 SciBooNE,PRD84(2011)012009 1. MiniBooNE 2. Beam 3. Detector 4. from K+-decay constraint 4. Oscillation ne 5. Discussion

SciBooNE is a scintillator tracker located on BNB (detector hall is used by ANNIE now) - neutrinos from kaon decay tend to be higher, and tend to make 3 tracks - from 3 track analysis, kaon decay neutrinos are constrained (0.85±0.11, prior is 40% error)

SciBooNE 3 track event

SciBooNE,PRD84(2011)012009

43 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from K+-decay constraint 4. Oscillation ne 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

SciBooNE 3 track event

ne from µ decay is constrained from nµCCQE measurement

SciBooNE,PRD84(2011)012009

ne from K decay is constrained from SciBooNE high energy nµ event measurement

44 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from K+-decay constraint 4. Oscillation ne 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement

ne from K decay is constrained from SciBooNE high energy nµ event measurement

45 13/06/18 MiniBooNE, PLB664(2008)41 1. MiniBooNE 2. Beam 3. Detector 4. from o constraint 4. Oscillation g p 5. Discussion

poàgg - not background, we can measure poàg - misID background, we cannot measure

The biggest systematics is production rate of po, because once you find that, the chance to make a single gamma ray is predictable.

We measure po production rate, and correct simulation with function of po momentum Asymmetric decay po po

NCpo event MiniBooNE, 46 PLB664(2008)4113/06/18 1. MiniBooNE 2. Beam 3. Detector 4. from o constraint 4. Oscillation g p 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement Asymmetric decay ne from K decay is po constrained from pSciBooNEo high energy nµ event NCpo measurement event MiniBooNE, 47 PLB664(2008)4113/06/18 1. MiniBooNE 2. Beam 3. Detector 4. NC constraint 4. Oscillation g 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement D resonance rate is constrained

from measured ne from K decay is NCpo rate constrained from SciBooNE high energy nµ event measurement

48 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. NC constraint 4. Oscillation g 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

�(∆→ ��) 3Γ = �(Δ → �� ) 2Γ� Asymmetric po Gg/Gp: NCg to NCp branching ratio po fraction (=2/3) decay is constrained n from µ decay e: p escaping factor e from measured is constrained CCpo rate (po®g) from nµCCQE measurement D resonance rate is constrained

from measured ne from K decay is NCpo rate constrained from SciBooNE high energy nµ event measurement

49 13/06/18 Lasorak, arXiv:1602.00084 1. MiniBooNE 2. Beam T2K, to be published (2018) 3. Detector 4. Neutrino NC single gamma production 4. Oscillation 5. Discussion radiative D-decay generalized Compton scattering anomaly mediated triangle diagram n n n n n n Z Z g g Z g D N w N N N N N N

A lot of new calculations T2K near detector measurement - all theoretical models and generators - T2K can only set a limit. Waiting more or less agree. NEUT has been fixed. Fermilab SBN to measure this channel.

Preliminary Pierre Lasorak 50 Queen Mary (T2K) 13/06/18 à Sussex (DUNE) 1. MiniBooNE 2. Beam 3. Detector 4. NC constraint 4. Oscillation g 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

from measured ne from K decay is NCpo rate constrained from SciBooNE high energy nµ event measurement

51 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. External constraint 4. Oscillation g 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement D resonance rate is constrained

from measured ne from K decay is NCpo rate constrained from SciBooNE high dirt rate is energy nµ event measured from measurement dirt data sample

52 13/06/18 MniBooNE, PRD82(2010)092005 1. MiniBooNE 2. Beam 3. Detector 4. External constraint 4. Oscillation g 5. Discussion

MiniBooNE detector has a simple geometry - Spherical Cherenkov detector - Homogeneous, large active veto We have number of internal measurement to understand distributions of external events.

e.g.) NC elastic candidates with function of Z Mis-modelling of external background is visible e.g.) Time of Flight Dirt related events is consistent with ToF data including oscillation hypothesis

misID (gamma)

intrinsic ne Dirt event (µ&K-decay) (external) Oscillation candidate (electron) 53 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. External constraint 4. Oscillation g 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement D resonance rate is constrained

from measured ne from K decay is NCpo rate constrained from SciBooNE high dirt rate is energy nµ event measured from measurement dirt data sample

54 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. Internal background constraints 4. Oscillation 5. Discussion

All backgrounds are internally constrained à intrinsic (beam ne) = flat à misID (gamma) = accumulate at low E

Asymmetric po decay is constrained ne from µ decay from measured is constrained CCpo rate (po®g) from nµCCQE measurement D resonance rate is constrained

from measured ne from K decay is NCpo rate constrained from SciBooNE high dirt rate is energy nµ event measured from measurement dirt data sample

Major backgrounds are all measured in other data 55 sample and their errors are constrained! 13/06/18 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion 1. MiniBooNE neutrino experiment

2. Booster Neutrino Beamline (BNB)

3. MiniBooNE detector

4. Oscillation candidate search

5. Discussion

13/06/18 56 1. MiniBooNE 2. Beam 3. Detector 5. Oscillation candidate event excess 4. Oscillation 5. Discussion

200 < EnQE < 1250 MeV - neutrino mode: Data = 1956 events Bkgd = 1577.8 ± 39.7(stat) ± 75.4(syst) à 381.2 ± 85.2 excess (4.5s)

Old data (50.3%) 162.0 event excess

New data (49.7%) 219.2 event excess

KS test suggests they are compatible P(KS)=76%

57 13/06/18 1. MiniBooNE 2. Beam 3. Detector 5. Oscillation candidate event excess 4. Oscillation 5. Discussion

200 < EnQE < 1250 MeV - neutrino mode: Data = 1959 events Bkgd = 1577.8 ± 39.7(stat) ± 75.4(syst) à 381.2 ± 85.2 excess (4.5s) - antineutrino mode: Data = 478 events Bkgd = 398.7 ± 20.0(stat) ± 20.3(syst) à 79.3 ± 28.6 excess (2.8s)

58 13/06/18 1. MiniBooNE 2. Beam 3. Detector 5. Oscillation candidate event excess 4. Oscillation 5. Discussion

Compatible with LSND excess within 2-neutrino oscillation hypothesis

However, appearance and disappearance data have a strong tension (Maltoni, Neutrino 2018)

59 13/06/18 1. MiniBooNE 2. Beam 3. Detector 5. Alternative photon production models? 4. Oscillation 5. Discussion

Excess look like more photons (misID) than electrons - peaked forward direction - shape match with po spectrum

Any misID background missing? - Internal po? - external po? - New NCg process? - New g production process?

60 13/06/18 Harvey,Hill,Hill, PRL99(2007)261601 n 1. MiniBooNE 2. Beam 3. Detector 5. Anomaly mediated production Z 4. Oscillation g 5. Discussion

A process within SM, but not considered. Z-boson omega n n meson Z g w N w Photon X X g Particle Zoo, http://www.particlezoo.net/ Later study found the contribution is small.

Hill, PRD84(2011)017501 Zhang and Serot, PLB719(2013)409 Wang et al, PLB740(2015)16

It looks it’s easy to forget any processes with s ~ 10-41 cm2 (e.g., diffractive po production s ~ 10-41 cm2 was identified very recently by MINERvA) MINERvA, PRL117(2016)111801 61 13/06/18 Gninenko, PRL103(2009)241802;PRD83(2011)015015 1. MiniBooNE 2. Beam 3. Detector 5. Heavy neutrino decay production 4. Oscillation g 5. Discussion

Carefully designed to avoid Karmen constraint. - The model works, but there are many “tricks” to avoid existing constraints, making the model bit artificial.

This model motivated NOMAD to look for such process. They didn’t find it and set limit. But this limit is higher energy region and below 3 GeV is still unknown. NOMAD, PLB706(2012)268 4m

T2K limit

3m NOMAD limit

SBND limit? NOMAD limit 2.7 ton fiducial mass Expected cross section

Pierre Lasorak Preliminary Queen Mary (T2K) 62 à Sussex (DUNE) 13/06/18 TK,Kostelecky,Tayloe,PRD74(2006)105009 1. MiniBooNE Diaz and Kostelecky, PLB700(2011)25 2. Beam 3. Detector 5. Alternative neutrino oscillation model? 4. Oscillation 5. Discussion tandem model effective Hamiltonian e.g.) Lorentz violation motivated neutrino oscillation model Making a new texture in Hamitonian to control oscillations. - my “tandem” model reproduce all data and LSND at the time of 2006 à not really reproduce details. puma model effective Hamiltonian

Advanced “puma” model was proposed, but this doesn’t reproduce long-baseline ne appearance data.

MiniBooNE (�) MiniBooNE (�̅)

KamLAND Solar

Atmospheric

Alternative oscillation models were popular in the beginning of oscillation physics time, but after Super-K’s L/E oscillatory shape measurement (2004), possible phenomenological models are extremely limited and all survived models have lots of “tricks” to avoid all constraints. Super-Kamiokande, PRL(2004)101801 63 13/06/18 1. MiniBooNE 2. Beam 3. Detector Conclusion 4. Oscillation 5. Discussion

MiniBooNE is the short-baseline neutirno oscillation experiments

After 15 years of running - neutrino mode: 381.2 ± 85.2 excess (4.5s) - antineutrino mode: 79.3 ± 28.6 excess (2.8s)

MiniBooNE has many legacies in this community - Many useful tools - Many useful people - Many new topics – Neutrino cross section measurements – Dark Matter production/detection search with neutrino detector MiniBooNE, PRL118(2017)221803 (ongoing) But the biggest legacy is the short-baseline anomaly

Thank you for your attention! 13/06/18 64 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 5. Discussion

backup

13/06/18 65 1. MiniBooNE 2. Beam 3. Detector 4. Oscillation 1. Cross section model 5. Discussion

Predicted event rates before cuts (NUANCE Monte Carlo) Casper, Nucl.Phys.Proc.Suppl.112(2002)161

Event neutrino energy (GeV)

13/06/18 66 1. MiniBooNE 2. Beam 3. Detector 4. PID cuts Oscillation candidate events 4. Oscillation 5. Discussion

4 PID cuts (a) Before PID cuts (b) After L(e/mu) cut (c) After L(e/po) cut (d) After mgg cut

Old and new data agree within 2% over 8 years separation.

67 13/06/18