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Neutrino Scattering Experiments at NUMI and Booster and J-PARC (Oh my). Kevin McFarland University of Rochester NUFACT 10 June 2003. Outline. What are the physics topics? Neutrinos Beyond Oscillations Neutrino beams: Now: FNAL Booster, KEK Future: FNAL NUMI, J-PARC n Detectors
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Neutrino Scattering Experiments atNUMI and Booster and J-PARC(Oh my) Kevin McFarland University of Rochester NUFACT 10 June 2003
Outline • What are the physics topics? • Neutrinos Beyond Oscillations • Neutrino beams: • Now: FNAL Booster, KEK • Future: FNAL NUMI, J-PARC n • Detectors • Some expected sample sizes • Thanks to: K2K, J-PARC n, MINERvA, FINeSE collaborations, A. Bodek, B. Fleming, C. Keppel, J. Morfin, T. Nakaya Kevin McFarland: Future Neutrino Scattering
Physics Motivation Kevin McFarland: Future Neutrino Scattering
Low Energy n Cross-Sections Neutrino interactions • Plausible models exist to describe some aspects of data in each region • Transitions between regions? • A dependence, final-state interactions, etc. • Quasi-Elastic / Elastic nmn→m-p (x =1, W=Mp) • Resonance nmp→m-pp (low Q2, W) • Deep Inelastic nmN→m-X (high Q2, W) Kevin McFarland: Future Neutrino Scattering
Sign of dm23 Sign of dm23 d d |Ue3| |Ue3| Precision P(nm→ne) and P(nm→nm) • Comparison of two precise measurements of nm→necan untangle magnitude and phase of Ue3 and mass hierarchy • n and anti-n measurements • or two n measurements at different E or L/E • This is not easy • low statistics and incoherent systematic uncertainties (Minakata et al.) Kevin McFarland: Future Neutrino Scattering
JHF->SK, 0.8MW-yr, 1ring FC m-like (JHFnu LOI) Reconstructed En (MeV) Where do Cross-Sections matter? • nm→nm, dm223, q23 • Signal is suppression in 600-800 MeV bin (peak of beam) • Dominated by non-QE background • 20% uncertainty in non-QE is comparable to statistical error • Non-QE background feeds down from En>Epeak • Quantitatively different for MINOS, NUMI-OA Oscillation with Dm2=3×10-3 sin22q=1.0 Non-QE No oscillation Kevin McFarland: Future Neutrino Scattering
sin22qme=0.05 (sin22qme0.5sin22q13) NUMI 0.7° OA, No NC/ne discrimination (detector indep.) (plot courtesy D. Harris) Where do Cross-Sections matter? • nm→ne, q13 • Shown at right is most optimistic q13; we may instead be fighting against background • NC p0 and beam ne background both in play • NC p0 cross-section poorly known • We can model sCC(ne)/sCC(nm). Is it right? • Precision measurement is the endgame Kevin McFarland: Future Neutrino Scattering
nm nm 50×nm 5×nm Where do Cross-Sections matter? NUMI 0.7° OA, 3.8E20 POT • nm→ne vs nm→ne, d • Cross-sections very different in two modes • “Wrong sign” background only relevant in anti-neutrino • Crucial systematic in comparing neutrino to anti-neutrino • Need sCC(n)/sCC(n) at high precision in sub- to few-GeV region Kevin McFarland: Future Neutrino Scattering
n–p0 nn+ Status of Cross-Sections • Not well-known at 1-few GeV • Knowledge of exclusive final states particularly poor • Understanding of backgrounds requires differential cross-sections for these processes! • A dependence? Kevin McFarland: Future Neutrino Scattering
Appealing to describe cross-sections in terms of quark-parton picture PDFs relate neutrino and charged-lepton cross-sections But wait… what about resonances? And what about non-perturbative region?(more later) F2 Understanding scattering for all Q2 Kevin McFarland: Future Neutrino Scattering
Quark-Hadron Duality • Duality between quark and hadron descriptions • relationship between confinement and asymptotic freedom • intimately related to nature and transition from non-perturbative to perturbative QCD Kevin McFarland: Future Neutrino Scattering
Duality in Structure Functions QPM predictions 2xF1 FL Resonance Data Kevin McFarland: Future Neutrino Scattering
Duality and Neutrino Scattering • Quark-Parton picture modulated by resonances • It seems so simple… but there is much to learn • Isospin selection of resonances in neutrino CC • Sum rules and incorporating the elastic peak • No information about axial contribution at low Q2 except from neutrino scattering program • Physics program tying together the electron and neutrino scattering communities Kevin McFarland: Future Neutrino Scattering
How well do we know quarks at high-x? • Ratio of CTEQ5M (solid) and MRST2001 (dotted) to CTEQ6 for the u and d quarks at Q2 = 10 GeV2. The shaded green envelopes demonstrate the range of possible distributions from the CTEQ6 error analysis. Kevin McFarland: Future Neutrino Scattering
Why is this? Isn’t there data? • Discrepancy between global fits and data • driven by differences between DIS and Drell-Yan • issues: non-PQCD to pQCD transition; d/u ratio Kevin McFarland: Future Neutrino Scattering
Higher Twist Effects • Higher Twist Effects are terms in the structure functions that behave like a power series in (1/Q2 ) or [Q2/(Q4+A)] • While pQCD predicts terms inas2 ( ~1/[ln(Q2/ L2)] )… as4 etc… • In the few GeV region, the termsof the two power series cannot be distinguished, experimentally or theoretically • Comparison of low and high Q2 data “measure” HTYang and Bodek: PRL 82, 2467 (1999) ;PRL 84, 3456 (2000); EPJ C13, 241 (2000); hep-ex/0203009 (2002) • Neutrino data: new vector in isospace (d/u), axial current Kevin McFarland: Future Neutrino Scattering
Nuclear Effects in Axial Current? Fermi motion Anti-shadowing “EMC” effect Shadowing • F2 / nucleon changes as a function of A. • Vector current measured (with high statistics) in -A • Axial current effects not well known; could, in principle, be different • Agreement between F2 and F2 … Kevin McFarland: Future Neutrino Scattering
Nuclear Effects • CCFR F2 and F2 … • high Q2 data • corrected for “5/18” • heavy flavor production implies ratio is not one • model predictions shown • high precision (1-2%) agreement at high x • not tightly constrained for x<<0.1 Kevin McFarland: Future Neutrino Scattering
Nuclear Effects in Axial Current? Fermi motion Anti-shadowing “EMC” effect Shadowing • F2 / nucleon changes as a function of A. • Vector current measured (with high statistics) in -A • Axial current effects not well known; could, in principle, be different • Agreement between F2 and F2 limits differences at high x • but effects in shadowing region low x possible? • Need improved measurements in - A Kevin McFarland: Future Neutrino Scattering
Nuclear Effects in Scattering in Shadowing Region • S.A.Kulagin has calculated shadowing for F2 • and xF3 in -A interactions. Stronger effect • than for m-A interactions • Shadowing in the low Q2 (A/VMD dominance) • region is much stronger than at higher Q2. Q2 = 15 GeV2 m-Ca/m-D Kevin McFarland: Future Neutrino Scattering
Higher Q2: Flavor Separated SFs Recall that Neutrinoshave the ability to directly resolve flavor of the nucleon’s constituents: interacts with d, s, u, and c while interacts with u, c, d and s. Using Leading order expressions: • Does s = s-bar and c = c-bar over all x? • If so..... Kevin McFarland: Future Neutrino Scattering
A Very Strange Asymmetry • Non-perturbative QCD effects could generate a strange vs. antistrange momentum asymmetry in the nucleon • decreasing at higher Q2 Brodsky and Ma, Phys. Let. B392 • At high Q2, can produce charm from scattering from strange sea • E.g., fits to NuTeV and CCFR n and dimuon data measure the strange and antistrange seas separately ( n s m c but ns mc ) Kevin McFarland: Future Neutrino Scattering
Laundry List: Other n-Scattering Physics • Quasi-elastic neutrino scattering and associated form-factors. • Contribution of the strange quark to proton spin through n elastic scattering. • sin2qW to check the recent surprising NuTeV result • ratio of NC / CC • as well as ds/dy from n-e scattering? • Strange particle production for Vus, flavor-changing neutral currents and measurements of hyperon polarization • important for atmospheric neutrino backgrounds to nucleon decay experiments! Kevin McFarland: Future Neutrino Scattering
Neutrino Beams: Now and Later K2K • K2K taking data now Kevin McFarland: Future Neutrino Scattering
n flux and direction K2K near detector suite 300m from the target (SciFi) (1Kton) (MRD) 312 ton (1ev / 20spills) Fid. Vol.: 6 ton 25 ton Kevin McFarland: Future Neutrino Scattering
New K2K Fine Grained Detector Fully active Large Volume: (300×300×166) cm3 ~15tons Finely segmented: 2.5×1.3×300 cm3 #channels : ~15,000 Kevin McFarland: Future Neutrino Scattering
miniBoonE detector horn to focus mesons towards detector 450 m baseline Decay region: mesons decay to neutrinos 8 GeV protons from FNAL Booster MiniBooNE detector FNAL Booster Neutrino Beamline Kevin McFarland: Future Neutrino Scattering
Status Booster Neutrino Beamline began delivering beam in August 2002 design intensity: 5 x 1020 protons per year 8 GeV beamline Be target Kevin McFarland: Future Neutrino Scattering
FINeSE at FNAL Booster • The Beam • New hall 100m from Target on-axis • <En >~0.9 GeV • 3×104/ton/3E20 POT (B. Fleming, NP02 talk) (Fleming, NP02) Kevin McFarland: Future Neutrino Scattering
NuMI Beamline at Fermilab MINERvA Main Injector ExpeRiment v-A Kevin McFarland: Future Neutrino Scattering
NuMI Neutrino Beam Configurations • Horn 1 position fixed; target and horn 2 moveable • Three “nominal” configurations: low-, medium-, high energy. Kevin McFarland: Future Neutrino Scattering
NuMI Near Hall ≈ 100 m underground Length: 45mHeight: 9.6mWidth: 9.5m Lots of real estate available… 26m upstream section Kevin McFarland: Future Neutrino Scattering
Off-Axis Beams • Exploits kinematics of meson decay to produce a narrow-band beam • To 0th order, beam spectrum is function of angle and meson count • Straightforward prediction of relative flux at different angles (energies) • ABSOLUTE flux contained by production data • E910, HARP, MIPP Kevin McFarland: Future Neutrino Scattering
Off-Axis Beams • Illustration at NUMI near detector site • Can scan through energies by changing detector angle • Width decreases • “quasi-monochromatic” • Rate significantly decreased at high angle On Axis 5m 10m NUMI LE Configuration 20m On Axis 5m NUMI ME 10m NUMI Near On and Off-Axis Beams (beam sim. courtesy M. Messier) 20m Kevin McFarland: Future Neutrino Scattering
Possible Sites • On-axis (near hall) andoff-axis sites at NUMI Kevin McFarland: Future Neutrino Scattering
Ditch 6m 10m 5m 4.5m Tunnel Dwelling • Not as nasty as one might think • Wide with high ceilings • separate personnel access to near hall • Flat floor, easy access to shaft • Relatively easy to bring utilities to site Kevin McFarland: Future Neutrino Scattering
Shaft Absorber Near Hall 15m Near (LE) Near (LE) Near (LE) 10m 5m Easy to go 5-15 meters Off-Axis • Detector can be moved around to vary energy Kevin McFarland: Future Neutrino Scattering
Rates at NUMI Near Hall • Expect 2.5 x 1020 pot per year of NuMI running. • Low E-configuration: • Events- (Em >0.35 GeV) Epeak = 3.0 GeV, <En> = 10.2 GeV, rate = 200 K events/ton - year. • Med E-configuration: • Events- Epeak = 7.0 GeV, <En> = 8.5 GeV, rate = 675 K events/ton - year • High E-configuration: • Events- Epeak = 12.0 GeV, <En> = 13.5 GeV, rate = 1575 K events/ton - year Kevin McFarland: Future Neutrino Scattering
Short Runs at High Energy Productive! • For example, 1 month neutrino plus 2 months anti-neutrino would yield: • 0.15 M n - events/ton • 0.08 M nbar - events/ton • DIS (W > 2 GeV, Q2 > 1.0 GeV2): • 70K n events / ton • 30K n-bar events / ton • Shadowing region (x < 0.1): • 25K events/ton Kevin McFarland: Future Neutrino Scattering
Low Energy NUMI Near Hall Kinematics Events / ton Q2 x W2 x (Q2>1, W>2 GeV) elastic + resonance Kevin McFarland: Future Neutrino Scattering
J-PARC neutrino and Near Detector HERE Kevin McFarland: Future Neutrino Scattering
J-PARC Neutrino Detector Hall (280m) 20mf Ground Level 11m target position 6.2m SK direction HK 3.7m 36m beam center with 3 off-axis. 6m Kevin McFarland: Future Neutrino Scattering
ND280off SK En (GeV) Far/Near ND280 Spectrum off-axis (2 degrees) similar spectrum as SK • measure n flux and the spectrum: selection of CC-QE • study n interaction • nonQE, p0, etc. • measure ne flux • measure nm flux (?) 2 degree off-axis w/ 50GeV 3.31014ppp ~4 events/100ton/spill 0.5 events/100ton/bunch Kevin McFarland: Future Neutrino Scattering
K2K SciBar Event Rates ~20K Events/10 tons fid. NUMI Near Off-Axis Event Rates/ton (courtesy C. McGrew) Comparisons • K2K vs NUMI off-axis • Lower rates by about an order of magnitude at <En>~1.2 GeV Kevin McFarland: Future Neutrino Scattering
NUMI Near Off-Axis Event Rates/ton Comparisons (Con’t) • FINeSE vs NUMI Off-Axis • at <En >~0.9 GeV • 100m from Target on-axis, rates and energies similar to NUMI at 1km from target, 20m OA • but 20m OA at NUMI requires a new (short) tunnel Kevin McFarland: Future Neutrino Scattering
Detectors for Neutrino Scattering Kevin McFarland: Future Neutrino Scattering
Detector: Physics Requirements • Good separation of NC and CC events • Good identification and energy measurement of m- and e± • Identification and separation of exclusive final states • Quasi-elastic mn–p, ene–p - observe recoil protons • Single0, ± final states - reconstruct 0 • Multi-particle final-state resonances • Reasonable EM and hadronic calorimetry for DIS • Accurate measurements of xBj, Q2 and W. • Multiple targets of different nuclei Kevin McFarland: Future Neutrino Scattering
Conceptual Design • Scintillator (CH) strips with fiber readout. Fully Active • (lint = 80 cm, X0 = 44 cm) • Add nuclear material with 2 cm thick planes of C, Fe and Pb. • 11 planes C = 1.0 ton (+Scintillator) • 3 planes Fe = 1.0 ton (+MINOS) • 2 planes Pb = 1.0 ton • Muon catcher: ideally magnetized m identifier / spectrometer • MINOS near detector is great for this! • Considering the use of side detectors for low-energy m-ID and shower energy. Kevin McFarland: Future Neutrino Scattering
Why plastic scintillator? Scintillator/Fiber R&D at Fermilab • Scintillation detector work at Fermilab • Scintillation Detector Development Laboratory • Extruded scintillator • Fiber characterization and test • Thin-Film facility • Fiber processing: Mirroring and coatings • Photocathode work • Diamond polishing • Machine Development • Diamond polishing • Optical connector development • High-density Photodetector packaging (VLPC) Scintillator Cost < $ 5 / kg Polymer Dopant • Triangles:1 cm base and transverse segmentation. • Yields about 1 mm position resolution for mips • From D0 pre-shower test data Kevin McFarland: Future Neutrino Scattering
Events in Scintillator Detector (courtesy David Potterveld) CC: En = 4.04 GeV, x = .43, y = .37 CC: En = 11.51 GeV, x = ..34, y = .94 “Elastic”: En = 3.3 GeV, x = .90, y = .08 NC: En = 29.3 GeV, x = ..25, y = .46 Kevin McFarland: Future Neutrino Scattering