status of the nova experiment - osaka university · 2016-11-09 · beam performance dbd16 -osaka,...

StatusoftheNOvAExperimentERIKACATAÑO-MUR (�� )

IOWA STATEUN IVERS ITY

FORTHENOVA COLLABORATION

DBD16 , NOVEMBER 9 , 2 016

NOvAoverview

2DBD16- OSAKA,JAPAN

§ NOvA isalong-baselineneutrinooscillationexperiment

§ StudyneutrinosfromNuMI beamatFermilab

§ 14mrad offthebeamaxis§ Twofunctionallyidenticalliquidscintillatordetectors:

§ FarDetector(FD)14kton;onthesurface

§ NearDetector(ND)0.3kton;undergroundMN WI

IL

MI

Near Detector

Far Detector

DBD16- OSAKA,JAPAN E.CATANO-MUR [ISU]– STATUSOFTHENOVAEXPERIMENT 3

20m

70m

Amonumentalexperiment…

ToweroftheSun


NOvA FD

(rotated)

NOvA ND

(rotated)

NOvA

collaborator

60m

15.6m

Amonumentalexperiment…

810km

NOvA’s physicsprogramOscillationchannels

!" → !$ !" → !$ “appearance”!" → !" !" → !" “disappearance”


§ Neutrino masshierarchy?§ %&' octant?§ Allowedrangeof()*?§ Precisionmeasurementsofsin. 2%&'

andΔ1'&& Otheranalyses:

§ Sterileneutrinos§ Crosssections§ Supernovae,

monopoles,etc.

§ 2015!$ analysisresults:PRL.116.151806§ 2015!" analysisresults:Phys.Rev.D93.051104§ 2016results:tobepublished

NuMI muonneutrinobeam

§ NuMI: neutrinosfromtheMainInjector

§ PartofFermilab’s acceleratorcomplex

DBD16- OSAKA,JAPAN 6

Maininjector(MI)

LinacBooster

NuMI

Neutrino

Beam

§ Linac: H- ions,400MeV

§ Booster:

protons,8GeV§ MainInjector:

protons,120GeV

§ TheseprotonsareusedtomaketheNuMI

beam

NuMI target

NuMI off-axis


§ MIprotonbeamissteeredontoanarrowgraphitetarget approx.1minlength

§ Producedhadronsarefocusedinandcharge-sign-selectedbytwomagnetichorns

§ 675mdecaypipe§ Predominantlypions andkaons,decaymodes34 → 54 + !" ,74 → 54 + !" ⟹ 9: beam

§ Smallcontamination:!$ , !

[GeV]νE0 5 10 15

CC

/ 6E2

0 PO

T / k

ton

/ 0.1

GeV

µν 0

5

10

15

On-Axis

7 mrad Off-Axis

A)ν14.6 mrad Off-Axis (NO

21 mrad Off-Axis

FLUKA11

A SimulationνNO

At14.6mrad off-axis,NOvA observesanarrowbandbeampeakedat2GeV§ Optimalfor!" → !$

BeamPerformance


§ Accumulatedexposure:6.05x1020 POTin14kton equivalentdetector§ Morethandoubleexposureof2015analysis§ ByJuly2016:runningat560kW(before3monthshutdown)§ Achieved700kWdesigngoalintestsonJune13!§ HighintensitybeamreturnsthisFriday

07/02/14 12/31/14 07/02/15 01/01/16 07/01/16

Bea

m P

ower

per

cal

enda

r hou

r (kW

)

0

100

200

300

400

500

600

700

Tota

l Pro

tons

(E20

)

0

2

4

6

8

10

12

14

DetectorCommissioning(ReducedMass)

FirstAnalysis2.74x1020 POT-equiv.

TotalExposure6.05x1020 POT-equiv.

POT=ProtonsOnTarget

NOvADetectors


§ PVC+LiquidScintillator§ MineralOil§ 5%pseudocumene

§ ReadoutviawavelengthshiftingfibertoAPD

§ Layeredplanesoforthogonalviews

§ ND:214layers,18000channels§ FD:896layers,344000channels

Findingneutrinoevents

DBD16- OSAKA,JAPAN 10 E.CATANO-MUR [ISU]– STATUSOFTHENOVAEXPERIMENT

§ Detectorsarefine-grained,low-Z,highly-activetrackingcalorimeters

§ Orthogonallayersà topandsideviewsforeachevent

§ Timeanddirectionhelptoidentifybeamevents

Findingneutrinoevents

Slicing:Coarseevent-leveltime-spaceclustering

Allhitsrecordedin550μsec(beam:~10μsec)

Selectedslicewithbeamcandidate

Vertexing:Findlinesofenergydepositions(CCevents:11cmresolution)

Clustering:Findclustersinangularspacearoundvertex.MergeviewsviatopologyandprongdE/dx

Tracking:Traceparticletrajectories

DBD16- OSAKA,JAPAN 11E.CATANO-MUR [ISU]– STATUSOFTHENOVAEXPERIMENT

q (ADC)10 102 310

q (ADC)10 102 310

q (ADC)10 102 310

νμ

eνe

p

μ

p

1m

1m

ν

νµ CC

νe CC

NC

Long,straighttrack

Shorter,wider,fuzzyshower

Hadronicactivityfromnuclearrecoilsystem

Eventtopologies


CC=chargedcurrent;NC=neutralcurrent

Eventselection(particleID)


§ !" selection:kNN basedonmuon tracklength,scattering,planefraction,dE/dx.RemovesmostNCbackgroundevents

§ !$ selection:featuresanewtechniquebasedonideasfromcomputervisionanddeeplearning

o “ConvolutionalVisualNetwork”(CVN)

o Input:Calibratedhitmapso Imageprocessing

transformationsà abstractfeatures

o Networkdecidesimportantfeatures+correlations

o Output: eventclassifier

A. Aurisano etal.,2016JINST11P09001

FEATURE MAPS

::

FEATURE MAPS

::

Muonneutrinodisappearance

1. Identifycontained!" CCeventsineachdetector

2. MeasureNearandFarenergyspectra

3. Extractoscillationinformationfromdifferencesbetweenbothenergyspectra


(simulated!5 CCevent)Ehad

Ltrack

!5 selectedeventsintheND


§ Reconstructed!5 energyisE! =E5 +Ehad

Hadronic energy (GeV)0 0.5 1 1.5 2 2.5 3

Eve

nts

310

0

100

200

300 Simulated selected eventsSimulated backgroundData

syst. rangeσShape-only 1- POT20 10×ND area norm., 3.72

NOvA Preliminary

Reconstructed muon energy (GeV)0 1 2 3 4 5

Eve

nts

310

0

20

40

60

80



NOvA Preliminary

Reconstructed neutrino energy (GeV)0 1 2 3 4 5

Eve

nts

310

0

100

200



NOvA Preliminary

§ UseNDdatatoimprovetheFDprediction:Unfoldthereconstructedneutrinoenergy+usethetrueFar/Nearratiofromthesimulation

Hadronic systemEvisible� Ehad

Reconstructedmuon tracklength� E5

!5 selectedeventsintheFD


§ PredictionusingNDdata:473±30withnooscillation

§ 78eventsobservedinFD


Ratio

with

uno

sc. (

bkg

subt

ract

ed)

0

0.5

1

1.5 POT-equiv.2010×NOvA 6.05

Data

Best fit prediction

NOvA Preliminary


Even

ts /

0.25

GeV

0

20

40

60

80

100

120 POT-equiv.2010×A 6.05νNO

Best fit prediction

Unoscillated prediction

Data

NOvA Preliminary

§ 82eventsatbestoscillationfit§ 3.7beambkgd.+2.9cosmic

Disappearanceresults


BestFit(inNH):

23θ2sin0.3 0.4 0.5 0.6 0.7

)2 e

V-3

(10

322m

∆

2

2.5

3

3.5

NOvA Preliminary

Normal Hierarchy POT-equiv.2010×NOvA 6.05

90% C.L. NOvA 2016

90% C.L. NOvA 2015

��m232

�� = 2.67± 0.12⇥ 10�3eV2

sin2 ✓23 = 0.40+0.03�0.02(0.63

+0.02�0.03)

Comparedto lastyearNOvA’s results

NoFeldman-CousinsCorrection

§ FitforΔm2 andsin2θ23§ Using2DGaussianC.L.(FCcorrected:tobepublished)

§ Maximalmixingexcludedat2.5σ

§ Dominantsystematiceffectsincludedinfit:§ Normalization§ NCbackground§ Flux§ Muon andhadronicenergyscales§ Crosssection§ Detectorresponseandnoise

Loweroctant Upperoctant

23θ2sin0.3 0.4 0.5 0.6 0.7

)2 e

V-3

(10

322m

∆

2

2.5

3

3.5

NOvA PreliminaryNormal Hierarchy, 90% CL

NOvA 2016

T2K 2014MINOS 2014

Disappearanceresults


BestFit(inNH):��m232

�� = 2.67± 0.12⇥ 10�3eV2

sin2 ✓23 = 0.40+0.03�0.02(0.63

+0.02�0.03)

Comparedtootherexperiments


§ FitforΔm2 andsin2θ23§ Using2DGaussianC.L.(FCcorrected:tobepublished)

§ Maximalmixingexcludedat2.5σ

§ Dominantsystematiceffectsincludedinfit:§ Normalization§ NCbackground§ Flux§ Muon andhadronicenergyscales§ Crosssection§ Detectorresponseandnoise

Electronneutrinoappearance


1. Identifycontained!$ (!")CCcandidatesineachdetector.

2. Usedatatoimprovethepredictionfromthesimulation:

• ND!" candidatesà !$ signalintheFD• ND!$ candidatesà FDbeambackgrounds

• FDdataoutsideofthebeamtimewindowàFDcosmicraybackground

3. InterpretanyFDdataexcessoverpredictedbackgroundsas!$ appearance

(simulated!e CCevent)

!eselectedeventsintheND

DBD16- OSAKA,JAPAN

E.CATANO-MUR [ISU]– STATUSOFTHENOVAEXPERIMENT 20

§ ND:select3components:beam!$CC,!"CC,NC

§ Correspondto3FDbackgrounds§ Beam!$CC:intrinsic!$ componentin

thebeam.IntheFD,!$ → !$ isabackgroundto!" → !$.Actual!$ eventsà scorehighonclassifier

§ !"CC,NC:eventsthataremisidentifiedas!$CCineitherdetector

§ TranslateNDdatatoaFDbkgd.expectation inenergyxPIDbinsusingFar/Nearratiosfromsimulation

§ ~10%excessofdataoverMC.Howtodivideamongcomponents?

classifiereνCVN 0.75 0.80 0.85 0.90 0.95 1.00

PO

T20

10

×Ev

ents

/ 3.

72

200

400

600

800

1000 ND dataTotal MCFlux Uncert.NC

CCeνBeam CCµν

NOvA Preliminary

Mostsignallike

Reconstructed neutrino energy (GeV)

PO

T20

10×Ev

ents

/ 3.

72

0

1000

2000

3000

NOvA Preliminary0.75 < CVN < 0.87 0.87 < CVN < 0.95 0.95 < CVN < 1

0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 5

Data

eνMC Beam

CCµνMC

MC NC

(Sameevents)

Data-drivenbackground(I)


§ Recall:dominantdecaymodes–NuMI beam:34 → 54 + !"74 → 54 + !"

§ Small!$ contamination“beam!$”54 → <4 + !$ + !"74 → <4 + !$

§ Wecanuse!"-selectedsamples(morestatistics,fewbackgrounds)tocorrectthenumbersofpionandkaon ancestors,andthusconstrainthebeam!$ CC

§ Usingdata:wefindcorrections~-2%forpions,+17%forkaons

True Neutrino Energy (GeV)0 5 10 15 20

Even

ts /

Bin

/ 6E2

0 PO

T

0

5

10

15

20

310×

All AncestorsOther Ancestor

Ancestor0LK Ancestor+K Ancestor+π

True!$ intheND

True Neutrino Energy (GeV)0 5 10 15 20

Even

ts /

Bin

/ 6E2

0 PO

T

0

1

2

3

4

610×

All AncestorsOther Ancestor

Ancestor0LK Ancestor+K Ancestor+π

True!" intheND

34

74

Data-drivenbackground(II)


Number of Michels0 1 2+

PO

T20

10×Ev

ents

/ 3.

72

0

5000

10000

15000

NOvA Preliminary

Data CCµνMC

MC NC

eνMC Beam

§ !"CC backgrounds:CCeventsthatdocontainamuon,butitstrackisnotclearlydefinedandit’smistakenfora!$ event

§ Containedevent:themuon decaysinsidethedetector.Dominantmodeis5= → <= + !$ + !"“Michel”electron

§ LookingforMichel-likeactivity,wecangetahandleonthe!"CC

§ Combiningthebeam!$ resultsandafittothenumberofMichels indataà all3componentsarecorrected

Averagecorrections:beam!$ upby4%,NCupby10%,!"CCupby17%


PO

T20

10×Ev

ents

/ 3.

72

0

1000

2000

3000

NOvA Preliminary0.75 < CVN < 0.87 0.87 < CVN < 0.95 0.95 < CVN < 1

0 1 2 3 4 0 1 2 3 4 0 1 2 3 4 5

Data

eνBeam CCµν

NCUncorrected MC

ElectronneutrinoFDprediction


TotalBG NC Beamνe νµ CC ντ CC Cosmics

8.2 3.7 3.1 0.7 0.1 0.5

NH,3π/2, IH,π/2,

28.2 11.2

Signalevents(±5%systematicuncertainty):

Backgroundbycomponent(±10%systematicuncertainty):

§ FDbeambkgd.estimatedusingNDdata

§ FDsignalexpectationispinnedtotheND-selected!"CCspectrum

§ FDcosmicbkgd. estimatedusingν? selectedFDdataoutsideofthebeamtimewindow

§ Expectedeventcountsdependonoscillationparameters

CPδ

Tota

l eve

nts

expe

cted

0

10

20

30

40

50

02π π

2π3 π2

POT equiv.2010×6.05NOvA FD =0.4-0.623θ2sin

NHIH

NOvA Simulation

ElectronneutrinoFDdata


NOvA - FNAL E929Run: 22242 / 18Event: 232856 / --UTC Mon Feb 15, 201604:36:13.437062336 sec)µt (

218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−


218 220 222 224 226 228

hits

110

210

q (ADC)10 210 310

hits

110

210

5000 5200 5400 5600 5800 6000

x (c

m)

500

600

700

z (cm)5000 5200 5400 5600 5800 6000

y (c

m)

600−

500−

400−

Observe33eventsinFD§ background8.2±0.8§ >8@ significanceof

appearance

CVN=0.991E=1.63GeV


Even

ts /

0.5

GeV

Bin

0

5

10

15

20

1 2 3 1 2 3 1 2 3

0.75 < CVN < 0.87 0.87 < CVN < 0.95 0.95 < CVN < 1NH

NOvA Preliminary

FD DataBest Fit Prediction Total BackgroundCosmic Background

POT equiv.2010×6.05

Appearanceresults


Fitforhierarchy,ACP,sin2θ23§ Using2DGaussianC.L.

(FCcorrected:tobepublished)§ Reactorconstraint(PDG2015)

sin2(2θ13)=0.085±0.05§ Δm2constraint(PDG2015)Δm2=2.44±0.06x10-3 eV2(-2.49±0.06x10-3 eV2, IH)

§ Systematiceffectsincludedasnuisanceparameters§ Normalization§ Flux§ Calibration§ Crosssection§ Detectorresponse

CPδ

23θ2sin

0

0.2

0.4

0.6

0.8

1

02π π

2π3 π2

NOvA Preliminary

σ1 σ2 σ3 NH

CPδ

23θ2sin

0

0.2

0.4

0.6

0.8

1

02π π

2π3 π2

NOvA Preliminary

σ1 σ2 σ3 IH


Appearanceresults


Fitforhierarchy,ACP,sin2θ23§ Reactorconstraint(PDG2015)

sin2(2θ13)=0.085±0.05§ ConstrainΔm2andsin2θ23with

NOvAdisappearanceresults*Notafulljoint fit,systematicsandotheroscillationparametersnotcorrelated

GlobalbestfitNormalHierarchy

§ 3σ exclusioninIH,loweroctantaroundACP=π/2

§ bestfitIH-NH,ΔB2=0.47§ bothoctantsandhierarchies

allowedat1σ CPδ

23θ2sin

0.2

0.3

0.4

0.5

0.6

0.7

02π π

2π3 π2

NOvA Preliminary

σ1 σ2 σ3 IH

CPδ

23θ2sin

0.2

0.3

0.4

0.5

0.6

0.7

02π π

2π3 π2

NOvA Preliminary

σ1 σ2 σ3 NH

�CP = 1.49⇡sin2(✓23) = 0.40


Anti-neutrinorunningà helpremovedegeneracies

Outlook


§ Below:sensitivitiesvstime,assumingfavoredoscillationparametersandmodestimprovementsintheanalysis

§ Startanti-neutrinorunningin2017;run50%neutrino50%anti-neutrinoafter2018

§ Inthenearterm(2018-19)expecttorejectWronghierarchyat>95%CLWrongoctantat>95%CLMax-mixingat>3sigma

Year2016 2018 2020 2022 2024

)σ

Sign

ifican

ce (

0

1

2

3

4

5

=0.02213θ2, sin2eV-310×=2.5322m∆

=0.40323θ2/2, sinπ=3CPδNormal

systematic uncertainty improvements2016 analysis techniques with projected

µν+eνNOvA joint Max. mixingHierarchyOctantCPV

NOvA Simulation

NH33/2Loweroctant

Year2016 2018 2020 2022 2024

)σ

Sign

ifican

ce (

0

1

2

3

4

5

=0.02213θ2, sin2eV-310×=2.5322m∆

=0.62523θ2/2, sinπ=3CPδNormal

systematic uncertainty improvements2016 analysis techniques with projected

µν+eνNOvA joint Max. mixingHierarchyOctantCPV

NOvA Simulation

NH33/2Upperoctant

Summary


§ With6.05x1020 POT,NOvA finds:§ Muonneutrinosdisappear:Bestfitisnon-maximal

§ Electronneutrinosappear:DataprefersNHatlowsignificance

§ Excellentdetectorandbeamperformance§ Lookingforwardtomoreneutrinodata+antineutrinorunningstartinginspring2017!§ %&' non-maximal?Octant?§ Masshierarchy?

§ Broadphysicsprogram!Sterileneutrinos,cross-sectionmeasurements,exoticsearches...


Even

ts /

0.5

GeV

Bin

0

5

10

15

20

1 2 3 1 2 3 1 2 3

0.75 < CVN < 0.87 0.87 < CVN < 0.95 0.95 < CVN < 1NH

NOvA Preliminary

FD DataBest Fit Prediction Total BackgroundCosmic Background

POT equiv.2010×6.05


Even

ts /

0.25

GeV

0

20

40

60

80

100

120 POT-equiv.2010×A 6.05νNO

Best fit prediction

Unoscillated prediction

Data

NOvA Preliminary

Thankyou!


Argonne,Atlantico,BanarasHinduUniversity,Caltech,Cochin,InstituteofPhysicsandComputerscienceoftheCzechAcademyofSciences,CharlesUniversity,Cincinnati,ColoradoState,CzechTechnicalUniversity,Delhi,JINR,Fermilab,Goiás,IITGuwahati,Harvard,IITHyderabad,U.Hyderabad,Indiana,IowaState,Jammu,Lebedev,MichiganState,Minnesota-TwinCities,Minnesota-Duluth, INRMoscow,Panjab,South Carolina,SDSchoolofMines,SMU,Stanford,Sussex,Tennessee,Texas-Austin,Tufts,UCL,Virginia,WichitaState,WilliamandMary,WinonaState

status of the nova experiment - osaka university · 2016-11-09 · beam performance dbd16 -osaka,...

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