Summary Near Detector at IDS Meeting in FNAL EuroNu Annual General Meeting, Strasbourg 3 June 2010 Paul Soler.

Summary Near Detector at Summary Near Detector at IDS Meeting in FNALIDS Meeting in FNAL

Summary Near Detector at Summary Near Detector at IDS Meeting in FNALIDS Meeting in FNAL

EuroNu Annual General Meeting, Strasbourg

3 June 2010Paul Soler

EuroNu AGM Strasbourg, 2 June 2010

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Near Detector AimsNear Detector Aims Currently there is no near detector baseline So far, we know that we need a near detector but not what it

looks like, nor how far away it should be from the decay ring We have decided on some of the essential measurements

that a Near Detector needs to do to reduce the neutrino oscillation systematics:– Measurement of neutrino flux and extrapolation to Far Detector– Measurement of charm (main background to oscillation signal)– Cross-section measurements: DIS, QEL, RES scattering

Other desirable measurements with Near Detector – Fundamental electroweak and QCD physics (ie PDFs)– Search for Non Standard Interactions (NSI) from taus

Have established links with LBNE near detector since many of the issues are similar


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Near Detector RationaleNear Detector Rationale Importance of Near Detector for systematics 2.5% error on flux makes big difference in CP coverage

Winter, Tang


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High Resolution Low Mass Near High Resolution Low Mass Near Detector Detector

Simulation near detector by Sofia group (Tsenov/Kharadzhov): GENIE+GEANT4, simple digitization, smearing but no reconstruction yet


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Flux Measurement at Near Detector Flux Measurement at Near Detector Tsenov/Kharadzhov showed how Inverse Muon Decay (IMD) can be

used for flux measurement: μ+e+ e

Best assumption for simulation: δθ~0.1mrad δp/p~1% δE/E~1%Shows parameters that we should strive for in the detector

1 hour NF!!!3.1x106 /year

Is ~1% flux error achievable?


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Flux extrapolation to far detector Flux extrapolation to far detector

• Hardly any change in error contours by adding ND information. • Still need to extract systematic error as function of and 13 from method

Flux extrapolation method based on matrix propagation.

Laing, PS


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Charm measurement Charm measurement Motivation: measure charm cross-section to

validate size of charm background in wrong-sign muon signature

Charm cross-section and branching fractions poorly known, especially close to threshold

Semiconductor vertex detector only viable option in high intensity environment (emulsion would perish)

CHORUS 2008


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Cross section measurementsCross section measurements Measurement of cross sections in DIS, QEL and RES. Coherent and diffractive Different nuclear targets: H2, D2

Nuclear effects, nuclear shadowing, reinteractions

At NUFACT, with modest

size targets can obtain very

large statistics, but is <1%

error achievable?

What is expected cross-

section errors from

MiniBoone, SciBoone,

T2K, Minerva, before

Neutrino Factory?


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Number Near DetectorsNumber Near Detectors Might need more than one detector at each decay ring straight sections

– While magnetic field not essential, it is preferable

Two detectors allows one also to measure divergence of beam ~0.1/, without Cherenkov monitor along decay straight


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Flux Observed by Near Detector Flux Observed by Near Detector

e

Near Detector sees a line source (755 long decay straight) Far Detector sees a point source

ee

130 m 1 km

130 m 1 km 2500 km

2500 kmNDND

NDND FD

FD


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Near Detector DesignNear Detector Design Overall design of near detector(s):

– We need near detector(s)– We don’t know what it/they should look like– However, we probably need:

• Vertex detector for charm and tau interactions for NSI (but beware of tau production from Ds decay!!)

• Low Z high resolution target (ie scintillating fibre tracker or capillary tube tracker) for flux and cross-section measurement (and e)

• Magnetic field for muon momentum measurement (δp/p~1%)

• Need muon catcher and electron identification• Good energy resolution for flux extrapolation (better than Far Detector) – aspire to

δE/E~1%

• Magnetic fields not essential for two (or more) detectors at each ring, but I think needed for momentum resolution

5th Neutrino Factory International Design Study Meeting FNAL, 9 April 2010

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Near Detector DesignNear Detector Design Near Detector elements:

– Vertex detector: Choice of Pixels (eg. Hybrid pixels, Monolithic Active Pixels …) or silicon strips

– Tracker: scintillating fibres, gaseous trackers (TPC, Drift chambers, straw tubes …)

– Other sub-detectors: PID, muon ID, calorimeter, …

Joint meeting of LBNE near detector proponents and IDS-NF near detector effort showed that there are areas of overlap and obvious synergies between both detector communities

Need to adapt these ideas for near detector at a neutrino factory.


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Bradford showed that a recycled Minerva detector could serve as near detector for LBNE: ideas also for neutrino factory

Minerva-like detectorMinerva-like detector

Outer calorimetry

Tracking volume of fine-grained scintillator

Readout PMT’s

LHe

Veto Wall

Cryotarget


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Hybrid design based around Minerva technology:

Hybrid Minerva designHybrid Minerva design

Tracking/calorimetry units: Minimize distance travels before hitting calorimetry (sign discrimination threshold ~200 MeV). Repeated units increase fiducial volume/statistics.

Side calorimetry Bradford


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Mishra argued strongly that identical near/far detectors are insufficient, so need high resolution near detector

High resolution near detectorHigh resolution near detector

Mishra


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High resolution magnetised detector (HiResM)

High resolution near detectorHigh resolution near detectorMishra


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NOMAD-like resolution in HiRes detector allows to:– Measure flux (low 0 method):

– Compare to Inverse Muon Decay– Measure absolute flux using -e

elastic scattering– Measure quasi-elastic scattering– Fermi motion– NC vs CC events (NOMAD with 90%

purity)– Coherent 0 – Measure A dependence in nuclear

targets

– Comparison sin2W from DIS and

– 77 different physics topics!

High resolution near detectorHigh resolution near detector

302000 1)():(

E

OA

C

EA

B

EEAEEN had

Mishra

ee)()(


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Muon chambers

EM calorimeter

HadronicCalorimeter

The previous design already looks like the detector configuration

that I have shown in the past (based on NOMAD and T2K): – Need also to add vertex detector in front

One possible designOne possible design


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Make design more similar to Far Detector:– Can have a high resolution Mini-TASD for leptonic

measurement and a mini-MIND for flux and muon measurement

– Vertex detector for charm measurement at the front.– Need to study options with detailed simulations

Another possibilityAnother possibility

beam3 m

3 m

B=1 T

~20 m

Mini-TASDMini-TASD95 t95 t

Mini-MINDMini-MIND460 t460 t

VertexVertexDetectorDetector

5th Neutrino Factory International Design Study Meeting FNAL, 9 April 2010

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Tasks and conclusionsTasks and conclusions Tasks:

– Simulation of near detector and optimisation of layout: benefit from common software framework for Far Detector

– Flux determination with inverse muon decays, etc.– Analysis of charm using near detector– Determination of systematic error from near/far

extrapolation– Expectation of cross-section measurements– Test beam activities to validate technology (eg. vertex

detectors, tracking detectors)– Construction of beam diagnostic prototypes– Other physics studies: PDFs, etc. (engage with theory

community for interesting measurements)

Summary Near Detector at IDS Meeting in FNAL EuroNu Annual General Meeting, Strasbourg 3 June 2010 Paul Soler.

Documents

near detector baseline

near detector tsenovkharadzhov

detector simulation

systematics o

euronu agm strasbourg

taus o

charm measurement o

flux measurement