1 Overview of the MINER A Experiment Vittorio Paolone(representing the MINER A Collaboration) University of Pittsburgh  Motivation  MINER A Detector  MINER A Physics Overview  MINER A and Oscillations  MINER A Status and Conclusions

5/31/06V. Paolone/UPitt2 Motivation Oscillation Measurements: We have entered a period of precision neutrino oscillation measurements …  Need Precision understanding of Low energy (Few GeV) neutrino Cross sections. Cross sections interesting in their own right:  Determination of Axial Form Factor  Duality with Neutrinos  Nuclear Effects  Coherent Pion Production See Bob Bradford’s Talk! From Talk given by Alfons Factory Scoping Study, RAL April 2006

5/31/06V. Paolone/UPitt3 Motivation Cont… Oscillation Measurements: - For NUMI/MINOS, Beamline expected distortion in energy distribution occurs For E < 3 GeV -Recall oscillation probability depends on E … However Experiments Measure E vis -E vis depends on Flux, , and detector response  Interaction multiplicities AND particle type produced Complications: - Near/Far fluxes are different -> Cross Section does not cancel in the ratio - Low Energy(few GeV) cross sections not well understood - Little data exists: Bubble Chamber -> low statistics and large systematics - Need large A (i.e. Fe) data - Therefore must use untested models to incorporate nuclear effects “Solution”: MINER A - Put fine grained detector in high rate neutrino beam - NUMI Beamline

5/31/06V. Paolone/UPitt4 MINER A Collaboration University of Athens, University of Dortmund, University of Minnesota –Duluth, Fermi National Accelerator Laboratory, Hampton University, Illinois Institute of Technology, Institute for Nuclear Research – Moscow, University of California – Irvine, Thomas Jefferson National Laboratory, James Madison University, Northwestern University, Pontificia Universidad Catolica del Peru, University of Pittsburgh, Rutgers - The State University of New Jersey Tufts University, Universidad Nacional de Ingenieria – Peru, University of Rochester, College of William & Mary, St. Xavier University (HEP Nuclear Theory)

5/31/06V. Paolone/UPitt5 MINER A Detector Front View Side View (Length is about 4 m). Active Target Mass ton total (MINOS ND) Inner Detector Hexagon – X, U, V planes for stereo view Outer Detector (OD) Layers of iron/scintillator for hadron calorimetry: 6 Towers Lead Sheets for EM calorimetry MINER A Side View

5/31/06V. Paolone/UPitt6 MINER A Detector Cont. Inner detector is totally active scintillator strip detector. Alternating planes rotated by 60 degrees to make 3 views (XUXV) Active elements are triangular bars of extruded scintillator with embedded 1.2 mm WLS fibers Readout by Hamamatsu M64 + FE Readout Based on existing TriP ASIC and LVDS chain: ADC (triple range) plus few ns resolution timing Prototype Board Detector Channel Count:  31,000 channels 80% in inner hexagon 20% in Outer detector  503 M-64 PMTs (64 channels)  128 pieces of scintillator per Inner Detector plane

5/31/06V. Paolone/UPitt7 MINER A Performance & Cost 1.7  3.3 cm 2 strips : Wave Length Shifting (WLS) fiber readout in center hole For the Inner Detector, scintillator is assembled into 128 strip scintillator planes:  ~3 mm in transverse direction from light sharing Charged particle Estimated Cost: ~14 Coordinate residual for different strip widths 4cm width 3cm width Light Output(per layer): ~$15M It’s a Bargain!

5/31/06V. Paolone/UPitt8 MINER A Physics Overview: Low Energy Neutrino Scattering We will be making precision measurements of low energy neutrino cross sections: Contributions to total cross section:  TOT =  QE +  RES +  DIS  QE : Quasi-elastic ->  RES : Resonance ->  DIS : Deep Inelastic Scattering -> : Inelastic, Low-multiplicity final states : Inelastic, High- multiplicity final states 110 (GeV)

5/31/06V. Paolone/UPitt9 Some MINER A Events     p Quasielastic event  n    p Neutral Current  0    A    Resonance production  p     ++   - p  +  p

5/31/06V. Paolone/UPitt10 Present State of Neutrino-Nucleon Cross section Measurements NuMI flux range: 1 to 20 GeV

5/31/06V. Paolone/UPitt11 MINER A Event Rates: Assumes 16.0x10 20 in LE, ME, and sHE NuMI beam configurations over 4 years Fiducial Volume: ~3 tons CH, ~0.6 t C, ~0.5t Fe and ~0.5t Pb Expected CC event samples: 8.6 M events in CH 1.4 M events in C 1.4 M events in Fe 1.4 M events in Pb Main CC Physics Topics (Statistics in CH)  Quasi-elastic 0.8 M events  Resonance Production 1.6 M total  Transition: Resonance to DIS2 M events  DIS, Structure Funcs. and high-x PDFs 4.1 M DIS events  Coherent Pion Production85 K CC / 37 K NC  Strange and Charm Particle Production > 230 K fully reconstructed NUMI Beams

5/31/06V. Paolone/UPitt12 MINER A and Oscillations Example: Nuclear Effects on MINOS Final State Interactions: -Intranuclear rescattering - Energy loss and/or absorption - Change in direction MINER A will perform measurements with high-A targets and high-statistics MINOS Iron Calorimeter - Nuclear effects among the largest systematics Changes measured visible energy Spectrum: Translate to shift in Far/Near ‘dip’ location ->  m 2

5/31/06V. Paolone/UPitt13 Example: MINER A and Oscillations Internuclear rescattering effects: Before MINER A  stat ~  syst ( rescattering only) After MINER A:  stat >>  syst ( rescattering only) Effect of this reduction on this systematic error increases “effective” POT by ~40% Savings on running the MI ~ $60M!

5/31/06V. Paolone/UPitt14 MINER A and Oscillations: NO A Off axis e appearance experiment: A significant Issue ->Backgrounds to e signal: Examples:  NC:  o 's in shower   -CC: High y +  o in shower  Beam e Also note near and far detector event samples will be dramatically different due to muon neutrino oscillations. - Therefore uncertainties in background and signal cross sections do not cancel completely between near and far detectors. A quantitative NO A study will take sometime to complete... (still trying to understand how different the near detector event samples will be from the far detector event samples with the totally active scintillator design)

5/31/06V. Paolone/UPitt15 MINER A Status and Schedule FNAL PAC Approval for MINER A: April 15 th 2004 Tests of detector elements and readout scheme – No show stoppers FNAL committed to MINER A: – Construction $$ in Oct – Sept – But FNAL budget is tight … – MINERvA has a high profile as only major accelerator experiment to start at lab before NO A If all goes well we should start taking data in

5/31/06V. Paolone/UPitt16 Conclusions MINER A will precisely study neutrino interactions at 1-20 GeV: - Using a fine-grained, high-resolution, detector - Using the high flux NuMI beam. MINER A will improve our knowledge of: - Neutrino cross sections at low energy, Low Q2. - A-Dependence in neutrino interactions (three targets C, Fe, Pb) These data will be interesting in there own right and will be important to minimize systematics errors in oscillation experiments. Turn on in