Neutrino Scattering Experiments at NUMI and Booster and J-PARC (Oh my) Kevin McFarland University of Rochester NUFACT 10 June 2003

Kevin McFarland: Future Neutrino Scattering 2 Outline  What are the physics topics? t Neutrinos Beyond Oscillations  Neutrino beams: t Now: FNAL Booster, KEK t Future: FNAL NUMI, J-PARC   Detectors  Some expected sample sizes  Thanks to: K2K, J-PARC, MINERvA, FINeSE collaborations, A. Bodek, B. Fleming, C. Keppel, J. Morfin, T. Nakaya

10 June 2003Kevin McFarland: Future Neutrino Scattering 3 Physics Motivation

10 June 2003Kevin McFarland: Future Neutrino Scattering 4 Low Energy Cross-Sections Neutrino interactions  Plausible models exist to describe some aspects of data in each region t Transitions between regions? t A dependence, final-state interactions, etc.  Quasi-Elastic / Elastic  n→  - p (x =1, W=M p )  Resonance  p→    p (low Q 2, W)  Deep Inelastic  N→  - X (high Q 2, W)

10 June 2003Kevin McFarland: Future Neutrino Scattering 5 Precision P(  → e ) and P(  →  )  Comparison of two precise measurements of  → e can untangle magnitude and phase of U e3 and mass hierarchy t and anti- measurements t or two measurements at different E or L/E t This is not easy »low statistics and incoherent systematic uncertainties Sign of  m 23  U e3 |  Sign of  m 23  U e3 |  (Minakata et al.)

10 June 2003Kevin McFarland: Future Neutrino Scattering 6 Where do Cross-Sections matter?   → ,  m 2 23,  23 t Signal is suppression in MeV bin (peak of beam)  Dominated by non-QE background t 20% uncertainty in non-QE is comparable to statistical error  Non-QE background feeds down from E >E peak  Quantitatively different for MINOS, NUMI-OA Oscillation with  m 2 =3×10 -3 sin 2 2  =1.0 No oscillation Non-QE JHF->SK, 0.8MW-yr, 1ring FC  -like Reconstructed E (MeV) (JHFnu LOI)

10 June 2003Kevin McFarland: Future Neutrino Scattering 7 Where do Cross-Sections matter?   → e,  13 t Shown at right is most optimistic  13 ; we may instead be fighting against background  NC  0 and beam e background both in play t NC  0 cross-section poorly known t We can model  CC ( e )/  CC (  ). Is it right?  Precision measurement is the endgame sin 2 2   e =0.05 (sin 2 2   e  0.5sin 2 2  13 ) NUMI 0.7° OA, No NC/ e discrimination (detector indep.) (plot courtesy D. Harris)

10 June 2003Kevin McFarland: Future Neutrino Scattering 8 Where do Cross-Sections matter?   → e vs  → e,  t Cross-sections very different in two modes t “ Wrong sign ” background only relevant in anti-neutrino »Crucial systematic in comparing neutrino to anti-neutrino  Need  CC ( )/  CC ( ) at high precision in sub- to few-GeV region 50×   5×   NUMI 0.7° OA, 3.8E20 POT

10 June 2003Kevin McFarland: Future Neutrino Scattering 9 Status of Cross-Sections  Not well-known at 1-few GeV t Knowledge of exclusive final states particularly poor t Understanding of backgrounds requires differential cross-sections for these processes! t A dependence? n  – p  0 n  n  +

10 June 2003Kevin McFarland: Future Neutrino Scattering 10 Understanding scattering for all Q 2  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) F2F2

10 June 2003Kevin McFarland: Future Neutrino Scattering 11  Duality between quark and hadron descriptions t relationship between confinement and asymptotic freedom t intimately related to nature and transition from non-perturbative to perturbative QCD Quark-Hadron Duality

10 June 2003Kevin McFarland: Future Neutrino Scattering 12 Duality in Structure Functions 2xF 1 FLFL QPM predictions Resonance Data

10 June 2003Kevin McFarland: Future Neutrino Scattering 13 Duality and Neutrino Scattering  Quark-Parton picture modulated by resonances  It seems so simple… but there is much to learn t Isospin selection of resonances in neutrino CC t Sum rules and incorporating the elastic peak t No information about axial contribution at low Q 2 except from neutrino scattering program  Physics program tying together the electron and neutrino scattering communities

10 June 2003Kevin McFarland: Future Neutrino Scattering 14 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 Q 2 = 10 GeV 2. The shaded green envelopes demonstrate the range of possible distributions from the CTEQ6 error analysis.

10 June 2003Kevin McFarland: Future Neutrino Scattering 15 Why is this? Isn’t there data?  Discrepancy between global fits and data t driven by differences between DIS and Drell-Yan t issues: non-PQCD to pQCD transition; d/u ratio

10 June 2003Kevin McFarland: Future Neutrino Scattering 16 Higher Twist Effects  Higher Twist Effects are terms in the structure functions that behave like a power series in (1/Q 2 ) or [Q 2 /(Q 4 +A)]  While pQCD predicts terms in  s 2 ( ~1/[ln(Q 2 /  2 )] )…  s 4 etc…  In the few GeV region, the terms of the two power series cannot be distinguished, experimentally or theoretically  Comparison of low and high Q 2 data “measure” HT Yang and Bodek: PRL 82, 2467 (1999) ;PRL 84, 3456 (2000); EPJ C13, 241 (2000); hep-ex/ (2002)  Neutrino data: new vector in isospace (d/u), axial current

10 June 2003Kevin McFarland: Future Neutrino Scattering 17  F 2 / nucleon changes as a function of A. t Vector current measured (with high statistics) in  -A t Axial current effects not well known; could, in principle, be different t Agreement between F 2 and F 2  … Shadowing Anti-shadowing “EMC” effect Fermi motion Nuclear Effects in Axial Current?

10 June 2003Kevin McFarland: Future Neutrino Scattering 18  CCFR F 2 and F 2  … t high Q 2 data  corrected for “5/18”  heavy flavor production implies ratio is not one t model predictions shown  high precision (1-2%) agreement at high x t not tightly constrained for x<<0.1 Nuclear Effects

10 June 2003Kevin McFarland: Future Neutrino Scattering 19  F 2 / nucleon changes as a function of A. t Vector current measured (with high statistics) in  -A t Axial current effects not well known; could, in principle, be different t Agreement between F 2 and F 2  limits differences at high x »but effects in shadowing region low x possible? t Need improved measurements in  Shadowing Anti-shadowing “EMC” effect Fermi motion Nuclear Effects in Axial Current?

10 June 2003Kevin McFarland: Future Neutrino Scattering 20 Q 2 = 15 GeV 2 S.A.Kulagin has calculated shadowing for F 2 and xF 3 in -A interactions. Stronger effect than for  -A interactions Shadowing in the low Q 2 (A/VMD dominance) region is much stronger than at higher Q 2.  -Ca/  -D Nuclear Effects in Scattering in Shadowing Region

10 June 2003Kevin McFarland: Future Neutrino Scattering 21 Higher Q 2 : Flavor Separated SFs  Does s = s-bar and c = c-bar over all x?  If so..... Using Leading order expressions: Recall that Neutrinos  have 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.

10 June 2003Kevin McFarland: Future Neutrino Scattering 22 A Very Strange Asymmetry  Non-perturbative QCD effects could generate a strange vs. antistrange momentum asymmetry in the nucleon t decreasing at higher Q 2 Brodsky and Ma, Phys. Let. B392  At high Q 2, can produce charm from scattering from strange sea  E.g., fits to NuTeV and CCFR  and  dimuon data measure the strange and antistrange seas separately (  s  c but   s   c )

10 June 2003Kevin McFarland: Future Neutrino Scattering 23  Quasi-elastic neutrino scattering and associated form-factors.  Contribution of the strange quark to proton spin through elastic scattering.  sin 2  W to check the recent surprising NuTeV result t ratio of NC / CC t as well as d  /dy from -e scattering?  Strange particle production for V us, flavor-changing neutral currents and measurements of hyperon polarization t important for atmospheric neutrino backgrounds to nucleon decay experiments! Laundry List: Other -Scattering Physics

10 June 2003Kevin McFarland: Future Neutrino Scattering 24 Neutrino Beams: Now and Later K2K  K2K taking data now

10 June 2003Kevin McFarland: Future Neutrino Scattering 25 K2K near detector suite flux and direction 312 ton (1ev / 20spills) 6 ton25 tonFid. Vol.: (MRD) (SciFi) (1Kton) 300m from the target

10 June 2003Kevin McFarland: Future Neutrino Scattering 26 New K2K Fine Grained Detector Large Volume: (300×300×166) cm 3 ~15tons Finely segmented: 2.5×1.3×300 cm 3 #channels : ～ 15,000 Fully active

10 June 2003Kevin McFarland: Future Neutrino Scattering 27 miniBoonE detector 450 m baseline 8 GeV protons from FNAL Booster horn to focus mesons towards detector Decay region: mesons decay to neutrinos MiniBooNE detector FNAL Booster Neutrino Beamline

10 June 2003Kevin McFarland: Future Neutrino Scattering 28 8 GeV beamline Booster Neutrino Beamline began delivering beam in August 2002 design intensity: 5 x protons per year Be target Status

10 June 2003Kevin McFarland: Future Neutrino Scattering 29 FINeSE at FNAL Booster  The Beam t New hall 100m from Target on-axis t ~0.9 GeV t 3×10 4 /ton/3E20 POT (B. Fleming, NP02 talk) (Fleming, NP02)

10 June 2003Kevin McFarland: Future Neutrino Scattering 30 NuMI Beamline at Fermilab MINERvA Main Injector ExpeRiment v-A

10 June 2003Kevin McFarland: Future Neutrino Scattering 31 NuMI Neutrino Beam Configurations  Horn 1 position fixed; target and horn 2 moveable  Three “nominal” configurations: low-, medium-, high energy.

10 June 2003Kevin McFarland: Future Neutrino Scattering 32 NuMI Near Hall ≈ 100 m underground Length: 45m Height: 9.6m Width: 9.5m Lots of real estate available… 26m upstream section

10 June 2003Kevin McFarland: Future Neutrino Scattering 33 Off-Axis Beams  Exploits kinematics of meson decay to produce a narrow-band beam  To 0 th order, beam spectrum is function of angle and meson count t Straightforward prediction of relative flux at different angles (energies) t ABSOLUTE flux contained by production data »E910, HARP, MIPP

10 June 2003Kevin McFarland: Future Neutrino Scattering 34 Off-Axis Beams  Illustration at NUMI near detector site t Can scan through energies by changing detector angle t Width decreases »“quasi-monochromatic” t Rate significantly decreased at high angle On Axis 5m 10m 20m On Axis 5m 10m 20m NUMI Near On and Off-Axis Beams (beam sim. courtesy M. Messier) NUMI LE Configuration NUMI ME

10 June 2003Kevin McFarland: Future Neutrino Scattering 35 Possible Sites  On-axis (near hall) and off-axis sites at NUMI

10 June 2003Kevin McFarland: Future Neutrino Scattering 36 Tunnel Dwelling  Not as nasty as one might think t Wide with high ceilings »separate personnel access to near hall t Flat floor, easy access to shaft »Relatively easy to bring utilities to site 10m 5m Ditch 4.5m 6m

10 June 2003Kevin McFarland: Future Neutrino Scattering 37 Easy to go 5-15 meters Off-Axis  Detector can be moved around to vary energy Shaft Near Hall Absorber Near (LE) 10m Near (LE) 5m Near (LE) 15m

10 June 2003Kevin McFarland: Future Neutrino Scattering 38  Expect 2.5 x pot per year of NuMI running.  Low E-configuration: t Events- (E  >0.35 GeV) E peak = 3.0 GeV, = 10.2 GeV, rate = 200 K events/ton - year.  Med E-configuration: t Events- E peak = 7.0 GeV, = 8.5 GeV, rate = 675 K events/ton - year  High E-configuration: t Events- E peak = 12.0 GeV, = 13.5 GeV, rate = 1575 K events/ton - year Rates at NUMI Near Hall

10 June 2003Kevin McFarland: Future Neutrino Scattering 39  For example, 1 month neutrino plus 2 months anti-neutrino would yield: t 0.15 M - events/ton t 0.08 M bar - events/ton  DIS (W > 2 GeV, Q 2 > 1.0 GeV 2 ): t 70K events / ton t 30K  bar events / ton  Shadowing region (x < 0.1): t 25K events/ton Short Runs at High Energy Productive!

10 June 2003Kevin McFarland: Future Neutrino Scattering 40 Events / ton elastic + resonance Low Energy NUMI Near Hall Kinematics x x (Q 2 >1, W>2 GeV) Q2Q2 W2W2

10 June 2003Kevin McFarland: Future Neutrino Scattering 41 J-PARC neutrino and Near Detector HERE

10 June 2003Kevin McFarland: Future Neutrino Scattering 42 J-PARC Neutrino Detector Hall (280m) 20m  36m SK direction beam center with 3  off-axis. 6m Ground Level target position 11m 3.7m 6.2m HK

10 June 2003Kevin McFarland: Future Neutrino Scattering 43 ND280 Spectrum off-axis (2 degrees) similar spectrum as SK measure flux and the spectrum: selection of CC-QE study interaction –nonQE,  , etc. measure e flux measure  flux (?) 2 degree off-axis w/ 50GeV 3.3  ppp ~4 events/100ton/spill  0.5 events/100ton/bunch E (GeV) SK ND280off Far/Near

10 June 2003Kevin McFarland: Future Neutrino Scattering 44 Comparisons  K2K vs NUMI off-axis t Lower rates by about an order of magnitude at ~1.2 GeV K2K SciBar Event Rates ~20K Events/10 tons fid. (courtesy C. McGrew) NUMI Near Off-Axis Event Rates/ton

10 June 2003Kevin McFarland: Future Neutrino Scattering 45 Comparisons (Con’t)  FINeSE vs NUMI Off-Axis t at ~0.9 GeV t 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 NUMI Near Off-Axis Event Rates/ton

10 June 2003Kevin McFarland: Future Neutrino Scattering 46 Detectors for Neutrino Scattering

10 June 2003Kevin McFarland: Future Neutrino Scattering 47 Detector: Physics Requirements  Good separation of NC and CC events t Good identification and energy measurement of  - and e ±  Identification and separation of exclusive final states t Quasi-elastic  n  – p, e n  e – p - observe recoil protons t Single  0,  ± final states - reconstruct  0 t Multi-particle final-state resonances  Reasonable EM and hadronic calorimetry for DIS t Accurate measurements of x Bj, Q 2 and W.  Multiple targets of different nuclei

10 June 2003Kevin McFarland: Future Neutrino Scattering 48 Conceptual Design  Scintillator (CH) strips with fiber readout. Fully Active t ( int = 80 cm, X 0 = 44 cm)  Add nuclear material with 2 cm thick planes of C, Fe and Pb. t 11 planes C = 1.0 ton (+Scintillator) t 3 planes Fe = 1.0 ton (+MINOS) t 2 planes Pb = 1.0 ton  Muon catcher: ideally magnetized  identifier / spectrometer t MINOS near detector is great for this!  Considering the use of side detectors for low-energy  -ID and shower energy.

10 June 2003Kevin McFarland: Future Neutrino Scattering 49 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) Triangles:1 cm base and transverse segmentation. Yields about 1 mm position resolution for mips From D0 pre-shower test data PolymerDopant Scintillator Cost < $ 5 / kg Why plastic scintillator? Scintillator/Fiber R&D at Fermilab

10 June 2003Kevin McFarland: Future Neutrino Scattering 50 Events in Scintillator Detector (courtesy David Potterveld) CC: E = 4.04 GeV, x =.43, y =.37 “Elastic”: E = 3.3 GeV, x =.90, y =.08 CC: E = GeV, x =..34, y =.94 NC: E = 29.3 GeV, x =..25, y =.46

10 June 2003Kevin McFarland: Future Neutrino Scattering 51 Read-out/Photo-Sensors to Consider  MAPMTs - very safe t Well-understood technology, know draw-backs, stable development t Relatively low QE t Not too pricey for M-64 (MINOS price order $20/channel) t Electronics cost non-trivial  CCD + I I - relatively inexpensive t Commercial off-the-shelf with integrated readout - inexpensive/channel t Relatively low QE t Slow device – probably no intra-spill timing

10 June 2003Kevin McFarland: Future Neutrino Scattering 52 Read-out/Photo-Sensors to Consider - continued  VLPC - “Cool” Devices t Not yet commercial but intense R&D development t For D0 cost order $50/channel »Bross speculates $10/channel “soon” t High QE t Requires cryogenic cooling to reduce noise  HPD and APD - Becoming commercial t High QE but low gain t Need high-gain electronics and some cooling (non-cryo) t Less pricey than MAPMT but electronics could cost a bundle

10 June 2003Kevin McFarland: Future Neutrino Scattering 53 Detector: Side  -ID/Spectrometer  These side detectors also function as a calorimeter for particles leaking out the side. t this is common in low energy events t too much plastic is required to contain shower t several schemes for adding absorber to edge and rear

10 June 2003Kevin McFarland: Future Neutrino Scattering 54 Large Volume: (300×300×166) cm 3 ~15tons Finely segmented: 2.5×1.3×300 cm 3 Large Light Yield: 7~20 photo-electrons/cm for MIP Particle ID: p/  : dE/dx  /  : range #channels : ～ 15,000 Proton Momentum: by dE/dx and range (Almost) Working Example:

10 June 2003Kevin McFarland: Future Neutrino Scattering 55 SciBar will be installed in summer 2003 Partial installation (4 layers out of 64) was done in the last December.

10 June 2003Kevin McFarland: Future Neutrino Scattering 56 A partial SciBar detector was installed in January The full installation will be conducted from July to September in (X,Y) layers

10 June 2003Kevin McFarland: Future Neutrino Scattering 57 Beam EventCosmic Ray EventLED Event

10 June 2003Kevin McFarland: Future Neutrino Scattering 58 K2K neutrino beam with ~200 keV threshold. Penetrating events only

10 June 2003Kevin McFarland: Future Neutrino Scattering photo-electrons/cm for one strip Attenuation Length ～ 360cm Fiber attenuation measured by cosmic-ray

10 June 2003Kevin McFarland: Future Neutrino Scattering 60 Event Rates on Nuclear Targets and DIS Kinematics

10 June 2003Kevin McFarland: Future Neutrino Scattering 61 H_2/D_2 MINOS Near Fid. vol: r = 80 cm. l = 150 cm. 350 K CC evts in LH K CC evts in LD 2 per year he- running. Technically easy/inexpensive to build and operate. Meeting safety specifications the major effort. Planes of C, Fe, Pb For part of run After initial (MINOS) run - add a Liquid H 2 /D 2 (/O/Ar) Target

10 June 2003Kevin McFarland: Future Neutrino Scattering 62 (2.5 x protons per year) Low MediumHigh Energy Energy Energy (3 years) (1 year, me- ) (1 year, he- ) (2 year, he - ) CH2.60 M2.10 M4.80 M 2.70 M C0.85 M0.70 M1.60 M 0.90 M Fe0.85 M0.70 M1.60 M 0.90 M Pb0.85 M0.70 M1.60 M 0.90 M LH M 0.20 M LD M 0.45 M NUMI Hall Detector (3 ton): Event Rates (CC w/ E  > 0.35 GeV)

10 June 2003Kevin McFarland: Future Neutrino Scattering 63 Ratio Fe/C: Statistical Errors from low energy Run x B j all DIS % n/a % ( running only) Statistics for Nuclear Effects Q 2 = 0.7 GeV 2

10 June 2003Kevin McFarland: Future Neutrino Scattering 64  Drell-Yan production results ( E-866) may indicate that high-x Bj (valence) quarks OVERESTIMATED.  A Jlab analysis of Jlab and SLAC high x DIS indicate high-x Bj quarks UNDERESTIMATED. ≈ Statistical Errors for 1 year of he- x Bj CHLH 2 LD %2.2%1.5% Measured / CTEQ6 CTEQ6 SLAC points Might be d/u ratio Physics Results: High-x Bj PDFs

10 June 2003Kevin McFarland: Future Neutrino Scattering 65 Conclusions

10 June 2003Kevin McFarland: Future Neutrino Scattering 66 Summary  Exciting possibilities in neutrino scattering physics at upcoming superbeam experiments t joint program between particle and nuclear physics communities  Design/proposal stage: t FINeSE (FNAL Booster) t MINERvA (FNAL NUMI) t J-PARC near detectors  Join us!