A High-Statistics Neutrino Scattering Experiment Using an On-Axis, Fine-grained Detector

1. MINERnA (Main INjector ExpeRiment n-A) A High-Statistics Neutrino Scattering Experiment Using an On-Axis, Fine-grained Detector in the NuMI Beam Quantitative Study of Low-energy n - Nucleus Interactions Northwestern University 7 February 2005 Jorge G. Morfín Fermilab

2. Neutrinos Are Everywhere! • Neutrinos outnumber ordinary matter particles in the Universe (electrons, protons, neutrons) by a huge factor. • Depending on their masses they may account for a fraction (few % ?) of the “dark matter” • Neutrinos are important for stellar dynamics: ~6.61010 cm-2s1 stream through the Earth from the sun. Neutrinos also govern Supernovae dynamics, and hence heavy element production. • If there is CP Violation in the neutrino sector, then neutrino physics might ultimately be responsible for Baryogenesis. • To understand the nature of the Universe in which we live we must understand the properties of the neutrino.

3. What are the Open Questions in Neutrino PhysicsFrom the APS Multi-Divisional Study on the Physics of Neutrinos • What are the masses of the neutrinos? • What is the pattern of mixing among the different types of neutrinos? • Are neutrinos their own antiparticles? • Do neutrinos violate the symmetry CP? • Are there “sterile” neutrinos? • Do neutrinos have unexpected or exotic properties? • What can neutrinos tell us about the models of new physics beyond the Standard Model? The answer to almost every one of these questions involves understanding how neutrinos interact with matter! Among the APS study assumptions about the current and future program: “determination of the neutrino reaction and production cross sections required for a precise understanding of neutrino-oscillation physics and the neutrino astronomy of astrophysical and cosmological sources. Our broad and exacting program of neutrino physics is built upon precise knowledge of how neutrinos interact with matter.”

4. The MINERnA Experiment Objectives of the Experiment Bring together the experts from two communities To use a uniquely intense and well-understoodn beam And a fine-grained, fully-activeneutrino detector To collect a large sample of n and nscatteringevents To perform a wide variety of n physics studies 1) The MINERnA Collaboration 2) Beam and Statistics 3) Survey of Physics Topics 4) Description and Performance of the Detector 5) Cost and Schedule 6) Summary

5. Bringing together experts from two communities to study low-energy n - NucleusPhysics G. Blazey, M.A.C. Cummings, V. Rykalin Northern Illinois University, DeKalb, Illinois W.K. Brooks, A. Bruell, R. Ent, D. Gaskell,, W. Melnitchouk, S. Wood Jefferson Lab, Newport News, Virginia S. Boyd, D. Naples, V. Paolone University of Pittsburgh, Pittsburgh, Pennsylvania A. Bodek, R. Bradford, H. Budd, J. Chvojka, P. de Babaro, S. Manly, K. McFarland, J. Park, W. Sakumoto University of Rochester, Rochester, New York R. Gilman, C. Glasshausser, X. Jiang, G. Kumbartzki, K. McCormick, R. Ransome Rutgers University, New Brunswick, New Jersey A. Chakravorty Saint Xavier University, Chicago, Illinois H. Gallagher, T. Kafka, W.A. Mann, W. Oliver Tufts University, Medford, Massachusetts J. Nelson, F.X.Yumiceva William and Mary College, Williamsburg, Virginia D. Drakoulakos, P. Stamoulis, G. Tzanakos, M. Zois University of Athens, Athens, Greece D. Casper, J. Dunmore, C. Regis, B. Ziemer University of California, Irvine, California E. Paschos University of Dortmund, Dortmund, Germany D. Boehnlein, D. A. Harris, M. Kostin, J.G. Morfin, A. Pla-Dalmau, P. Rubinov, P. Shanahan, P. Spentzouris Fermi National Accelerator Laboratory, Batavia, Illinois M.E. Christy, W. Hinton, C.E .Keppel Hampton University, Hampton, Virginia R. Burnstein, O. Kamaev, N. Solomey Illinois Institute of Technology, Chicago, Illinois S.Kulagin Institute for Nuclear Research, Moscow, Russia I. Niculescu. G. .Niculescu James Madison University, Harrisonburg, Virginia Red = HEP, Blue = NP, Black = Theorist

6. To use a uniquely intense andwell-understoodn beam. The NuMI Beam.

7. The NuMI Beam Configurations. For MINOS, the majority of the running will be in the “low-energy” (LE) configuration. There will be shorter runs at higher energies as well.

8. To collect a large sample ofn and nscatteringevents… • LE-configuration: Events- (Em >0.35 GeV) Epeak = 3.0 GeV, <En> = 10.2 GeV, rate = 60 K events/ton - 1020 pot • sME-configuration: Events- Epeak = 6.0 GeV, <En> = 8.0 GeV, rate = 132 K events/ton - 1020 pot (ME = 230 K events/ton - 1020 pot) • sHE-configuration: Events- Epeak = 9.0 GeV, <En> = 12.0 GeV, rate = 212 K events/ton - 1020 pot (HE = 525 K events/ton - 1020 pot) Move Target Only Move Target and Second Horn With E-907 at Fermilab to measure particle spectra from the NuMI target, expect to know neutrino flux to ≈±4 - 5%.

9. MINERnA will have the statistics to cover awide variety of important n physics topics Assume9x1020 POT: MINOS chooses 7.0x1020 in LE n beam, 1.2x1020 in sME and 0.8x1020 in sHE Typical Fiducial Volume = 3-5 tons CH, 0.6 ton C, ≈ 1 ton Fe and ≈ 1 ton Pb 2 - 3.5 M events in CH 0.5 M events in C .75 M events in Fe .75 M events in Pb nm Event Rates per fiducial ton Process CC NC Quasi-elastic 82 K 27 K Resonance 156 K 48 K Transition 164 K 52 K DIS 336 K 100 K Coherent 7 K 3.5 K TOTAL 745 K 228 K Main Physics Topics with Expected Produced Statistics • Quasi-elastic 250-400 K events off 3-5 tons CH • Resonance Production 470 K total, 350 K 1p • Coherent Pion Production 20 K CC / 10 K NC • Nuclear Effects C:0.5 M, Fe: .75 M and Pb: .75 M • DIS and Structure Functions 1 M DIS events • Strange and Charm Particle Production > 60 K fully reconstructed events • Generalized Parton Distributionsfew K events

10. Why study low-energy n scattering physics?Motivation: NP - Compliment Jlab study of the nucleon and nucleus Significant overlap with JLab physics kinematic region and introduces the axial-vector current Four major topics: Nucleon Form Factors - particularly the axial vector FF Duality - transition from resonance to DIS (non-perturbative to perturbative QCD) Parton Distribution Functions - particularly high-xBJ Generalized Parton Distributions - multi-dimensional description of partons within the nucleon

11. Why study low-energy n scattering physics? Motivation: EPP - Neutrino Oscillation Experiment Systematics NuMI Off-axis Neutrino Beam We need to improve our understanding of low energy n-Nucleus interactions for oscillation experiments! 1 10 MINOS: Neutrino Beam

12. How MINERnA Would Help MINOS How Nuclear Effects enter Dm2 Measurement Measurement of Dm2 with MINOS • Need to understand the relationship between the incoming neutrino energy and the visible energy in the detector • Expected from MINERnA • Improve understanding of pion and nucleon absorption • Understand intra-nuclear scattering effects • Understand how to extrapolate these effects from one A to another • Improve measurement of pion production cross-sections • Understand low-n shadowing with neutrinos

13. How MINERnA Would Help NOnA/T2K: Total fractional error in the predictions as a function of Near Detector off-axis Angle Current Accuracy of Low-energy Cross-sections DQE = 20% DRES = 40% DDIS = 20% DCOHFe = 100% With MINERnA Measurements of s DQE = 5% DRES = 5, 10% (CC, NC) DDIS = 5% DCOHFe = 20%

14. Okay, Motivation is there however - Haven’t we measured these s and effects long ago?Exclusive Cross-sections at Low En: Quasi-elastic - DISMAL n n S. Zeller - NuInt04 • World sample statistics is still fairly miserable! • Cross-section important for understanding low-energy atmospheric neutrino oscillation results. • Needed for all low energy neutrino monte carlos. • Best way to accurately measure the axial-vector form factors K2K and MiniBooNe

15. Exclusive Cross-sections at Low En :1-Pion and Strange Particle- DISMAL Typical samples of NC 1-p • ANL •  p n + (7 events) •  n n 0 (7 events) • Gargamelle •  p p 0 (240 evts) •  n n 0 (31 evts) • K2K and MiniBooNe • Starting a careful analysis of single 0 production. Strange Particle Production • Gargamelle-PS - 15 L events. • FNAL - ≈ 100 events • ZGS - 30 events • BNL - 8 events • Larger NOMAD sample expected CC p–p+ S. Zeller - NuInt04 n–p0 n–n+

16. How about sTot? • Low energy (< 10 GeV) primarily from the 70’s and 80’s suffering from low statistics and large systematics (mainly from n flux measurements). • Mainly bubble chamber results --> larger correction for missing neutrals. • How well do we model sTot? D. Naples - NuInt02

17. 1.2 EMC NMC 1.1 E139 E665 1 0.9 0.8 0.7 1 0.001 0.01 0.1 Knowledge of Nuclear Effects with Neutrinos: essentially NON-EXISTENT Fermi motion shadowing EMC effect x sea quark valence quark • F2 / nucleon changes as a function of A. Measured in /e - A not in  - A • Good reason to consider nuclear effects are DIFFERENT in  - A. • Presence of axial-vector current. • SPECULATION: Much stronger shadowing for  -A but somewhat weaker “EMC” effect. • Different nuclear effects for valance and sea --> different shadowing for xF3 compared to F2. • Different nuclear effects for d and u quarks.

18. Nuclear EffectsA Difference in Nuclear Effects of Valence and Sea Quarks? • Nuclear effects similar in Drell-Yan and DIS for x < 0.1. Then no “anti-shadowing” in D-Y while “anti-shadowing” seen in DIS (5-8% effect in NMC). Indication of difference in nuclear effects between valence & sea quarks? • This quantified via Nuclear Parton Distribution Functions: K.J. Eskola et al and S. Kumano et al

19. High xBj parton distributionsHow 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. • Recent high-x measurements indicate conflicting deviations from CTEQ: E-866 uV too high, NuTeV uV & dV too low • CTEQ / MINERnA working group to investigate high-xBj region.

20. MINERnA n Scattering Physics Program • Quasi-elastic • Resonance Production - 1pi • Resonance Production - npi, transition region - resonance to DIS • Deep-Inelastic Scattering • Coherent Pion Production • Strange and Charm Particle Production • sT , Structure Functions and PDFs • s(x) and c(x) • High-x parton distribution functions • Nuclear Effects • Spin-dependent parton distribution functions • Generalized Parton Distributions

21. What detector properties do we needto do this physics? • Must reconstruct exclusive final states • high granularity for charged tracking, particle ID, low momentum thresholds, • e.g. mn–p • But also must contain • electromagnetic showers (0, e±) • high momentum hadrons (±, p, etc.) • from CC need ± (enough to measure momentum) • Nuclear targets for the study of neutrino induced nuclear effects

22. n …fine-grained, fully-activeneutrino detector • Active target of scintillator bars (6t total, 3 - 5 t fiducial) • Surrounded by calorimeters • upstream calorimeters are Pb, Fe targets (~1t each) • magnetized side and downstream tracker/calorimeter C, Fe and Pb Nuclear targets Coil

23. Active Target Module • Planes of strips are hexagonal • inner detector: active scintillator strip tracker rotated by 60º to get stereo U and V views • Pb “washers” around outer 15 cm of active target • outer detector: frame, HCAL, spectrometer • XUXV planes  module Inner, fully-activestrip detector Outer Detectormagnetized sampling calorimeter

24. Extruded Scintillator and Optics Basic element: 1.7x3.3cm triangular strips. 1.2mm WLS fiber readout in center hole Assemble into planes

25. Absorbers between planes e.g., E- or H-CAL,nuclear targets Extruded Scintillator and Optics Basic element: 1.7x3.3cm triangular strips. 1.2mm WLS fiber readout in center hole Assemble into planes

26. HCAL Calorimeters • Three types of calorimeters in MINERnA • ECAL: between each sampling plane,1/16” Pb laminated with 10mil stainless (X0/3) • HCAL: between each sampling plane, 1” steel (l0/6) • OD: 4” and 2” steel between radial sampling layers • ECAL and HCAL absorbers are plates, rings DSECAL SideECAL

27. Electronics/DAQ System • Data rate is modest • ~1 MByte/spill • but many sources!(~31000 channels) • Front-end board based on existing TriP ASIC • sample and hold in up to four time slices • few ns TDC, 2 range ADC • C-W HV. One board/PMT • DAQ and Slow Control • Front-end/computer interface • Distribute trigger and synchronization • Three VME crates + server

28. Coordinate residual for different strip widths 3cm width(blue and green are different thicknesses) 4cm width 3.3cm Performance: Optimization of Tracking in Active Target • Excellent tracking resolution w/ triangular extrusion • s~3 mm in transverse direction from light sharing • More effective than rectangles (resolution/segmentation) • Key resolution parameters: • transverse segmentation and light yield • longitudinal segmentation for z vertex determination • technique pioneered by D0upgrade pre-shower detector

29. Performance: p0 Energy and Angle Reconstruction • p0’s cleanly identified • p0 energy resolution: 6%/sqrt(E) • p0 angular resolution better than smearing from physics Coherent, resonance events withp0

30. Performance: Particle Identification Chi2 differences between right and best wrong hypothesis • Particle ID by dE/dx in strips and endpoint activity • Many dE/dx samples for good discrimination p K p R = 1.5 m - p: m =.45 GeV/c, p = .51, K = .86, P = 1.2 R = .75 m - p: m =.29 GeV/c, p = .32, K = .62, P = .93

31. nuclear targets active detector ECAL HCAL Performance: Quasi-elastic mn–p • Reminder: proton tracks from quasi-elastic events are typically short. Want sensitivity to pp~ 300 - 500 MeV • “Thickness” of track proportional to dE/dx in figure below • proton and muon tracks are clearly resolved • precise determination of vertex and measurement of Q2 from tracking p n m

32. nuclear targets active detector ECAL HCAL Performance: 0 Production • two photons clearly resolved (tracked). can find vertex. • some photons shower in ID,some in side ECAL (Pb absorber) region • photon energy resolution is ~6%/sqrt(E) (average) g n g

33. Location in NuMI Near Hall • MINERnA preferred running position is as close as possible to MINOS, using MINOS as high energy muon spectrometer

34. MINERA CC Quasi-Elastic MeasurementsFully simulated analysis, - realistic detector simulation and reconstruction • Quasi-elastic (n + n --> m-+ p, around 300 K events) • Precision measurement of s(En) and ds/dQ important for neutrino oscillation studies. • Precision determination of axial vector form factor (FA), particularly at high Q2 • Study of proton intra-nuclear scattering and their A-dependence (C, Fe and Pb targets) Average: eff. = 74 % and purity = 77% Expected MiniBooNE and K2K measurements

35. n/m± n p0 /p± Z/W N N P Coherent Pion ProductionFully simulated analysis, - realistic detector simulation and reconstruction • Coherent Pion Production(n + A --> n /m- + A + p, 20 K CC / 10 K NC) • Precision measurement of s(E) for NC and CC channels • Measurement of A-dependence • Comparison with theoretical models signal Selection criteria reduce the signal by a factor of three - while reducing the background by a factor of ≈ 1000.

36. Coherent Pion Production Rein-Seghal Paschos- Kartavtsev MINERnA’s nuclear targets allow the first measurement of the A-dependence of scoh across a wide A range MINERnA Expected MiniBooNe and K2K measurements

37. Resonance Production - D • Resonance Production (e.g. n + N -->n /m- + D, 600 K total, 450K 1p) • Precision measurement of s and ds/dQfor individual channels • Detailed comparison with dynamic models, comparison of electro- & photo production, the resonance-DIS transition region -- duality • Study of nuclear effects and their A-dependence e.g. 1 p<-- > 2 p <--> 3 p final states Total Cross-section and ds/dQ2 for the D++ - Errors are statistical only sT

38. Nuclear Effects Q2 distribution for SciBar detector Problem has existed for over two years • All “known” nuclear effects taken into account: • Pauli suppression, Fermi Motion, Final State Interactions • They have not included low-n shadowing that is only • allowed with axial-vector (Boris Kopeliovich at NuInt04) • Lc = 2n / (mp2 + Q2) ≥ RA (not mA2) • Lc100 times shorter with mp allowing low n-low Q2 shadowing • ONLY MEASURABLE VIA NEUTRINO - NUCLEUS • INTERACTIONS! MINERnA WILL MEASURE THIS • ACROSS A WIDE n AND Q2 RANGE WITH C : Fe : Pb Larger than expected rollover at low Q2 MiniBooNE From J. Raaf (NOON04)

39. Nuclear EffectsDifference between n-A and m-A nuclear effects Sergey Kulagin

40. Strange and Charm Particle Production Existing Strange Particle Production Gargamelle-PS - 15 L events. FNAL - ≈ 100 events ZGS -30 events BNL - 8 events Larger NOMAD inclusive sample expected • Theory: Initial attempts at a predictive phenomenology stalled in the 70’s due to lack of constraining data. • MINERvA will focus on exclusive channel strange particle production - fully reconstructed events (small fraction of total events) but still . • Important for background calculations of nucleon decay experiments • With extended n running could study single hyperon production to greatly extend form factor analyses • New measurements of charm production near threshold which will improve the determination of the charm-quark effective mass. MINERnA Exclusive States 100x earlier samples 3 tons and 4 years DS = 0 m- K+ L0 10.5 K m- p0K+ L0 9.5 K m- p+ K0 L0 6.5 K m- K-K+ p5.0 K m- K0K+ p0p1.5 K DS = 1 m- K+ p 16.0 K m- K0 p 2.5 K m- p+ K0n 2.0 K DS = 0 - Neutral Current nK+L0 3.5 K nK0L0 1.0 K nK0L0 3.0 K

41. Cost and Schedule SummariesG&A and Contingency included 52.7% 11.5% 21.0% 14.8% FNAL $ > 33% FNAL $ > 66%

42. Schedule26 months: design, fabrication and installation • Many immediately starting projects: purchases, or continuing design work • Plane assembly, fiber, PMT factories run ASAP until almost project end • Project uses simultaneous plane assembly, module assembly and installation • Electronics is done earlier than appears; installation in PMT box is last step

43. Milestones • December 2002 - Two EOIs for neutrino scattering experiments using the NuMI beam and similar detector concepts presented to the PAC. PAC suggests uniting efforts and preparing proposal. • December 2003 - MINERnA proposal presented to PAC. PAC requests more quantitative physics studies and details of MINERnA’s impact on Fermilab. • January 2004 -Submit proposal for MRI funding support (maximum $2M) of partial detector to NSF. Rejected due to no guarantee for funding rest of detector. • March 2004 - MINERnA Impact Statement submitted to Directorate and presented to an Impact Review Committee. • April 2004 - Proposal addendum containing additional physics studies and report from the Impact Review Committee presented to PAC. Receive Stage I approval. • Summer 2004 - Very Successful R&D Program concentrating on front-end electronics, scintillator extrusions and a “vertical slice test” • October 2004 - Proposal to NP and EPP of NSF to fund MINERnA. • December 2004 - Proposal to NP and HEP of DOE to fund MINERnA. • January 2005 - First (successful) Director’s Review of MINERnA Submit MRI to construct the inner detector.

44. Summary • MINERnA, a recently approved experiment, brings together the expertise of the HEP and NP communities to address the challenges of low-energy n-A physics. • MINERnA will accumulate significantly more events in important exclusive channels across a wider En range than currently available. With excellent knowledge of the beam, s will be well-measured. • With C, Fe and Pb targets MINERnA will enable a systematic study of nuclear effects in n-A interactions, known to be different than well-studied e-A channels. • MINERnA results will dramatically improve the systematic errors of current and future neutrino oscillation experiments. • We welcome additional collaborators!!

45. BACKUP SLIDES

46. How MINERnA Helps NonA/T2K:Background Predictions Total fractional error in the background predictions as a function of Near Detector off-axis Angle Current Accuracy of Cross-sections DQE = 20% DRES = 40% DDIS = 20% DCOHFe = 100% With MINERnA Measurements of s DQE = 5% DRES = 5, 10% (CC, NC) DDIS = 5% DCOHFe = 20% With MINERnA measurements of cross sections, decrease fractional error on background prediction by a factor of FOUR

47. fully active area R&D Goals for this summer -Electronics / Vertical Slice Test • Phase 1: Testing the TriP Chip • Test board being designed by P. Rubinov (PPD/EE); piggy back on D0 work • Reads out 16 channels of a MINOS M64 in a spare MINOS PMT box • (coming from MINOS CalDet) • Questions: • Noise and signal when integrating over 10 ms. • Test self-triggering and external triggering mode for storing charge. • Test the dynamic range (2 TriP Channels / PMT channel) • Procedure to get timing from the TriP chip. Phase 2: Test our full system Build a small tracking array in the new muon lab using strips and fibers of the proposed design and the readout system from Phase 1. Use CR and b sources. • Questions: • Light yield – does it match our expectations? • Spatial resolution via light sharing in a plane • Timing • Uniformity Late summer Early summer

48. partial side view, many detector modules coil Calorimeters (cont’d) • OD: 4” and 2” steel between radial sampling layers • coil at bottom of the detector provides field in steel OD steel OD strips coil pass-through

49. Extruding Scintillator • Process is inline continuous extrusion • improvementover batchprocessing(MINOS) • Tremendous capacity at Lab 5 • the 18 tons of MINERnA in < 2 months, including startup and shutdown time

50. Extruding Scintillator (cont’d) • Design of the die in order to achieve the desired scintillator profile • collaboration with NIU Mech. E. department(Kostic and Kim) simulation of performance (design tool) 2x1cm rect. die developed at NIU for Lab 5