Neutrinos from STORed Muons, nuSTORM

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Neutrinos from STORed Muons,

nuSTORM

JB. Lagrange

Imperial College, UK/Fermilab, USA

On behalf of nuSTORM collaboration

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JB Lagrange - ICHEP 14 - July 14

Overview!

Facility!

Neutrino flux

Outline

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Overview!

Facility!

Neutrino flux

Outline

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Overview

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1. Facility to provide a muon beam for precision neutrino interaction physics (GeV-scale high-statistics νe & νe data for the first time)!

!

2. Study of sterile neutrinos (appearance &

disappearance for ν & ν)!

!

3. Accelerator & Detector technology test bed!

Introduction

The nuSTORM Facility

120 GeV proton beam incident on a graphite target produce pions.

Pions are horn captured, transported, and injected into ring.

52% of pions decay to muons before first turn

Muons within momentum acceptance circulate in ring.

Muon lifetime is 27 orbits of decay ring.

Schematic representation of nuSTORM

Ryan Bayes (University of Glasgow) nuSTORM Interaction Physics 28 May, 2014 4 / 14

!

Potential for intense low energy muon beam!

Enables μ decay ring R&D (instrumentation) & technology demonstration platform ! Provides a neutrino Detector Test Facility!

Test bed for a new type of conventional neutrino beam

⇡ ! µ + ¯ ⌫

_µ

⇡

⁺

! µ

⁺

+ ⌫

_µ

µ ! e + ¯ ⌫

_e

+ ⌫

_µ

µ

⁺

! e

⁺

+ ⌫

_e

+ ¯ ⌫

_µ

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Implementation,,at,FNAL:,

Benefits,from,existing,extraction,tunnel;,

Ideal,baseline,from,storage,ring,to,D0,assembly,building:,

Space,and,infrastructure,for,SuperBIND,and,LAr,detector;,

Space,and,access,for,near,detector,

,

Implementation at FNAL

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Scope:

nuSTORM Facility near site

Alan Bross nuSTORM Workshop, Fermilab November 21st, 2013 4

µ decay ring: P = 3.8 GeV/c ± 10%

Near site view

Implementation at FNAL (2)

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Implementation at CERN

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Implementation,,at,CERN:,

Principal,issue:,

SPS,spill,is,10, :,

Implies,bend,for,proton,or,pion,beam,

Or,development,of,fast,extraction, ,

Two,options:,

NA,implementation:,

Possible,exploitation,of,synergies,with,ICARUS/NESSiE,

NAHtoHWA,implementation:,

Advantage,is,proton/pion,bend,not,required;,

Longer,baseline,must,be,tuned,to,larger,muon,energy, (possible),

,

Implementation,,at,CERN:,

Principal,issue:,

SPS,spill,is,10, :,

Implies,bend,for,proton,or,pion,beam,

Or,development,of,fast,extraction, ,

Two,options:,

NA,implementation:,

Possible,exploitation,of,synergies,with,ICARUS/NESSiE,

NAHtoHWA,implementation:,

Advantage,is,proton/pion,bend,not,required;,

Longer,baseline,must,be,tuned,to,larger,muon,energy, (possible),

,

Proposed by E. Wildner.

SPS

ISR

Decay ring

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Overview!

Facility!

Neutrino flux

Outline

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Facility

100 kW target station (designed for 400 kW)!

120 GeV protons from MI (FNAL), or 100 GeV protons from SPS (CERN)!

Horn to collect pions (π⁺ or π^-)!

Target material Carbon or Inconel!

10²¹ protons on target over 4-5 years (3x10¹⁸ useful muon decays)!

Collection and transport!

Chicane to select charge of pions!

Stochastic injection!

Racetrack decay ring!

large aperture FODO or FFAG.

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Stochastic injection

concept from D. Neufer*: injection of pions at the Beam Combination Section (BCS) that decay in the

straight section in muons.!

No kicker!

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Injection scheme

!  π’s are on an injection orbit

!  separated by chicane

!  µ’s are in ring circulating orbit

!  lower p ~3.8 GeV/c

!  ~30cm separation between

Alan Bross NuFact 2013 - IHEP August 24th, 2013 22

!  Concept works for FODO lattice

!  Now detailed by Ao Liu

!  Beam Combination Section (BCS)

David Neuffer’s original concept from 1980

Fermilab, Indiana University

Ao Liu

Pion Beamline Definition

• The pion beamline consists of the transport beamline, the beam combination section (BCS), and the storage ring production straight shared by π and µ.

• The pion beamline is designed with reference momentum P₀=5 GeV/c, the simulation was initially done using π+ collected by a NuMI-like horn with slightly different lengths and target position, no full optimization.

5/28/14 ₉

Pion Beamline

BCS

*Telmark Conference on neutrino mass, 1980

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Decay ring: FODO

FODO ring based on SC separated function

magnets in the arcs.!

Only quadrupoles in the straight sections.!

zero dispersion kept in the straight section.

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FODO ring design for nuSTORM

Ring Layout

Optics in the FODO ring

FODO ring design is based on SC separated function magnets in the arc

Only quads are used in the straight sections

Zero dispersion is kept in straight section.

FODO ring design for nuSTORM

Ring Layout

Optics in the FODO ring

FODO ring design is based on SC separated function magnets in the arc

Only quads are used in the straight sections

Zero dispersion is kept in straight section.

muon 3.8 GeV/c ± 10% (no chromatic correction)!

Circumference: 480 m, straight section length: 180 m

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Decay ring: RFFAG

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muon 3.8 GeV/c ± 16% (zero-chromatic system)!

Circumference: 500 m, straight section length: 175 m

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Overview!

Facility!

Neutrino flux

Outline

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Hybrid facility

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Stochastic injection gives access to a pion beam decaying in the straight section as well as muon beam decay.

⇡ ! µ + ¯ ⌫

_µ

⇡

⁺

! µ

⁺

+ ⌫

_µ

µ ! e + ¯ ⌫

_e

+ ⌫

_µ

µ

⁺

! e

⁺

+ ⌫

_e

+ ¯ ⌫

_µ

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Flux from muon decays at near detector

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Flux at a near detector 50m from the end of the decay straight with a 3m radius

μ+ μ-

νμ NC 1,174,710 νe NC 1,002,240 νe NC 1,817,810 νμ NC 2,074,930 νμ CC 3,030,510 νe CC 2,519,840 νe CC 5,188,050 νμ CC 6,060,580

Rates / 100T for 10

²¹

POT

50 m from the end of the decay straight with a 3 m radius.

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2 km from the end of the decay straight with a 3 m radius. !

Full muon simulation and decays!

Shift to higher energy due to kinematics effect

Flux at a fr detector 2km from the end of the decay straight with a 3m radius – full muon simulation and decays

* far detector performance for sterile neutrino searches documented:

Light sterile neutrino sensitivity at the nuSTORM facility Phys. Rev. D 89, 071301(R)

Far detector performance for sterile neutrino searches:

Light sterile neutrino sensitivity at the nuSTORM facility, Phys. Rev. D 89, 071301(R)

Flux from muon decays at !

far detector

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Sterile neutrinos studies

Assume sample of 10¹⁸ useful µ⁺ decays!

1.3 kTon iron-scintillator calorimeter detector.!

Assume a 0.5% rate and 0.5% cross-sectional systematic.!

In absence of interaction studies 0.5%→5%

17 Physics Case for Neutrino Interactions at nuSTORM

Sterile Neutrino Studies

¹

Assume sample of 1⇥10¹⁸ useful µ⁺ decays.

1.3 kTon iron-scinitillator calorimeter detector.

Assume a 0.5% rate and 0.5% cross-sectional systematic.

In absence of interaction studies 0.5%!5%.

⌫_e ! ⌫_µ Appearance Search

0.1 1 10

0.0001 0.001 0.01 0.1

∆m2 [ev2 ]

sin²2θ_eµ

10σ, 1% Sys 99% C.L., 1% Sys 10σ, 5% Sys 99% C.L., 5% Sys 99% C.L. Fit to Evid.

99% C.L. Fit to App.

99% C.L. Icarus

¯

⌫_µ ! ⌫¯_µ Disappearance Search

0.1 1 10

0.01 0.1

∆m2 [ev2 ]

sin²2θ_µµ 99%, 1% Sys., Dis.

99%, 5% Sys., Dis.

99% Fit to Dis. Data

1D. Adey et. al. Phys. Rev. D 89, 071301(R)

10σ

99% C.L.

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Interaction studies

Interaction rates must be understood by type.

(Dictate significance of

systematics in oscillations)!

Many interaction types only accessible with

nuSTORM.!

Very little data in ν

e

interactions.

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Physics Case for Neutrino Interactions at nuSTORM

Interaction Specific Studies at nuSTORM

Interaction rates must be understood by type.

Dictates significance of systematic effects in oscillations.

Many interaction types only accessible with

nuSTORM beams Data deficient in ⌫

_e

interactions.

Muon storage ring the best known

method to fill this gap.

, GeV

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5E

/nucleon2 cm-38 10 CCQE

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

2 _MiniBooNE

ANL BNL GGM SERP SKAT

-p n µ

µ

, GeV E

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

+n e

ep

ID Stored µ⁺ Stored µ

1 ⌫¯_µp ! µ⁺n ⌫_µn ! µ⁺p 2 ⌫_en ! e p ⌫¯_ep ! e⁺n 3 ⌫¯_µn ! µ⁺⇡ n ⌫_µn ! µ ⇡⁺n 4 ⌫¯_µp ! µ⁺⇡⁰p ⌫_µn ! µ ⇡⁰p 5 ⌫¯_µp ! µ⁺⇡ p ⌫_µp ! µ ⇡⁺p 6 ⌫_en ! e ⇡⁺n ⌫¯_en ! e⁺⇡ n 7 ⌫_ep ! e ⇡⁰p ⌫¯_ep ! e⁺⇡⁰n 8 ⌫_ep ! e ⇡⁺p ⌫¯_ep ! e⁺⇡ p 9 ⌫¯_µ,⌫_e ! X ⌫_µ,⌫¯_e ! X

¯

⌫_µp ! µ⁺n

⌫_µn ! µ ⇡⁺n

⌫_µn ! µ ⇡⁰p

⌫_µp ! µ ⇡⁺p

⌫_µn ! µ p

Interaction channels ^{data exist}

Gargamelle data from 70s, !

New results coming T2K and Minerνa

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Beam uncertainty study

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nuSTORM Near Detector Physics Potential

Beam Uncertainty Study

Generated muon beam with dispersion inflated by 2%.

Expect transverse µ beam uncertainty of < 1%.

Rate Difference

nue2pc

Entries 3

Mean 3917

RMS 976.9

Energy MeV

0 1000 2000 3000 4000

Divergence (102% - 100%) / 102% -0.1 -0.05 0 0.05 0.1

nue2pc

Entries 3

Mean 3917

RMS 976.9

Divergence (1.02 - 1.00 / 1.02) ν

-0.02 -0.01 0 0.01 0.02

N

0 1000 2000 3000 4000 5000 6000 7000 8000

9000 _Entries ^df ₇₀

Mean -0.001335 RMS 0.005517

Bin errors from 2% divergence error

RMS of bin-to-bin change less than 0.6%

Expect less than 0.3% uncertainty

Beam divergence errors Muon beam divergence inflated by 2% and

compared with nominal case – less than 1% bin errors

Divergence resolution of 1% achievable with

diagnostics

Muon beam divergence inflated by 2% and compared with nominal case.

<1% bin errors.

Divergence resolution of 1%

achievable with diagnostics in the ring.

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Near detector flux from ! pion/kaon decay

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Energy (MeV)

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000

POT @ 50m20 / 102 / 50MeV / mν

1011

1012

1013

1014

1015

νµ + → π

νµ + → K

νµ + → µ

νe

→

+

µ

νe + → K

νe + → π

νµ - → π

µ⁺ ! ⌫_e µ⁺ ! ⌫¯_µ

⇡⁺ ! ⌫_µ

⇡ ! ⌫¯_µ

⇡⁺ ! ⌫_e K⁺ ! ⌫_e K⁺ ! ⌫_µ

One path in the straight section, at 50 m

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Cross-section measurement

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nuSTORM Near Detector Physics Potential

Potential for Cross-Section Measurement

Flux uncertainties a significant contribution to cross-sections

Experiment Flux Error MiniBooNE 6.7—10.5%

T2K 10.9%

Minerva 12%

nuSTORM <1%

Event Rate per 10²¹ POT, 100 tonnes at 50 m

µ⁺ µ

Channel N_evts Channel N_evts

¯

⌫_µ NC 1,174,710 ⌫¯_e NC 1,002,240

⌫_e NC 1,817,810 ⌫_µ NC 2,074,930

¯

⌫_µ CC 3,030,510 ⌫¯_e CC 2,519,840

⌫_e CC 5,188,050 ⌫_µ CC 6,060,580

⇡⁺ ⇡

⌫_µ NC 14,384,192 ⌫¯_µ NC 6,986,343

⌫_µ CC 41,053,300 ⌫¯_µ CC 19,939,704

nuSTORM measurements limited by detector systematics.

Energy (MeV) ν

0 1000 2000 3000 4000 5000

POT @ 50m21 Events / 50MeV / 10ν 0

2000 4000 6000 8000 10000 12000 14000

Decay in 100 t Argon

+

Events from µ νe

Energy (MeV) ν

0 1000 2000 3000 4000 5000

1000 2000 3000 4000 5000 6000 7000 8000

+

Events from µ

µ

ν

Energy (MeV)

0 1000 2000 3000 4000 5000

POT @ 50m20 / 102 / 50MeV / mν

0 50 100 150 200 250

3

10

× Events from π⁺ decay in 100 t Argon

µ

ν

Ryan Bayes (University of Glasgow) nuSTORM Interaction Physics 28 May, 2014 9 / 14 nuSTORM Near Detector Physics Potential

Potential for Cross-Section Measurement

Experiment Flux Error MiniBooNE 6.7—10.5%

T2K 10.9%

Minerva 12%

nuSTORM <1%

Event Rate per 10²¹ POT, 100 tonnes at 50 m

µ⁺ µ

Channel N_evts Channel N_evts

⌫¯_µ NC 1,174,710 ⌫¯_e NC 1,002,240

⌫_e NC 1,817,810 ⌫_µ NC 2,074,930

¯

⌫_µ CC 3,030,510 ⌫¯_e CC 2,519,840

⌫_e CC 5,188,050 ⌫_µ CC 6,060,580

⇡⁺ ⇡

⌫_µ NC 14,384,192 ⌫¯_µ NC 6,986,343

⌫_µ CC 41,053,300 ⌫¯_µ CC 19,939,704

Energy (MeV) ν

0 1000 2000 3000 4000 5000

2000 4000 6000 8000 10000 12000 14000

+

Events from µ νe

Energy (MeV) ν

0 1000 2000 3000 4000 5000

1000 2000 3000 4000 5000 6000 7000 8000

+

µ Events from

µ

ν

Energy (MeV)

0 1000 2000 3000 4000 5000

POT @ 50m20 / 102 / 50MeV / mν

0 50 100 150 200 250

3

×10 Events from π⁺ decay in 100 t Argon

µ

ν

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Summary

nuSTORM produces a new type of conventional neutrino beam from pion decay!

Facility with a strong physics interest:!

Sterile neutrino search!

Cross-section measurements!

long-baseline oscillation search!

Accelerator and detector R&D test bed

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Thank you for your attention

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