Published on October 9, 2007
The Neutrino Flux At MiniBooNE.: The Neutrino Flux At MiniBooNE. The BooNE Collaboration: The BooNE Collaboration Y. Liu, I. Stancu University of Alabama, Tuscaloosa, AL 35487 S. Koutsoliotas Bucknell University, Lewisburg, PA 17837 E. Hawker, R. A. Johnson, J. L. Raaf University of Cincinnati, Cincinnati, OH 45221 T. Hart, R. H. Nelson, E. D. Zimmerman University of Colorado, Boulder, CO 80309 A. A. Aguilar-Arevalo, L. Bugel, J. M. Conrad, J. Formaggio, J. Link, J. Monroe, D. Schmitz, M. H. Shaevitz, M. Sorel, G. P. Zeller Columbia University, Nevis Labs, Irvington, NY 10533 D. Smith Embry Riddle Aeronautical University, Prescott, AZ 86301 L. Bartoszek, C. Bhat, S. J. Brice, B. C. Brown, D. A. Finley, B. T. Fleming, R. Ford, F. G. Garcia, P. Kasper, T. Kobilarcik, I. Kourbanis, A. Malensek, W. Marsh, P. Martin, F. Mills, C. Moore, P. Nienaber, E. Prebys, A. D. Russell, P. Spentzouris, R. Stefanski, T. Williams Fermi National Accelerator Laboratory, Batavia, IL 60510 D. Cox, A. Green, H. Meyer, R. Tayloe Indiana University, Bloomington, IN 47405 G. T. Garvey, C. Green, W. C. Louis, G. A. McGregor, S. McKenney, G. B. Mills, V. Sandberg, B. Sapp, R. Schirato, N. Walbridge, R. Van de Water, D. H. White Los Alamos National Laboratory, Los Alamos, NM 87545 R. Imlay, W. Metcalf, M. Sung, M. O. Wascko Louisiana State University, Baton Rouge, LA 70803 J. Cao, Y. Liu, B. P. Roe University of Michigan, Ann Arbor, MI 48109 A. O. Bazarko, P. D. Meyers, R. B. Patterson, F. C. Shoemaker, H. A. Tanaka Princeton University, Princeton, NJ 08544 MiniBooNE Overview: MiniBooNE Overview The FNAL Booster delivers 8 GeV protons to the MiniBooNE beamline. The protons hit a beryllium target producing pions and kaons. The magnetic horn focuses the secondary particles towards the detector. The mesons decay, and the neutrinos fly to the detector. Signal from p+®m+ nm …then… nm ®ne …which produces… e- in the detector. Meson Production in the Target: Meson Production in the Target Sanford-Wang parameterizations (pions): Cho Fit. K2K Fit. JAM Fit (MiniBooNE internal). MARS Monte Carlo (pions and kaons†). GFLUKA Monte Carlo (pions and kaons). †MARS does not store neutral kaons and so these are constructed from K+ using the GFLUKA K0L/K+ yield ratio. Sanford-Wang Parameterization: Sanford-Wang Parameterization Empirical parameterization with 8 free parameters: where: Pπ is the momentum of the pion. Pp is the momentum of the proton. Θπ is the production angle of the pion in the lab frame. c1-8 are the parameters determined by fitting to available data. Detector Pion Acceptance: Detector Pion Acceptance MARS production model used. momentum angle S-W Fit Results: S-W Fit Results MiniBooNE fit (Jocelyn Monroe, Columbia University) used the following data: Vorontsov,1983. Cho, 1971. Marmer, 1969. Dekkers, 1964 (subset). Vorontsov 1983.: Vorontsov 1983. Cho 1971.: Cho 1971. Marmer 1969.: Marmer 1969. Dekkers 1964.: Dekkers 1964. Beamline Modeling: Beamline Modeling GEANT 4 Monte Carlo used for beam simulations. Meson productions models from external sources (MARS, GFLUKA, S-W etc.) are implemented within G4. GEANT 4 implementation principally by Michel Sorel, Columbia University. Neutrino flux which intersects the detector is boosted by redecaying mesons. GEANT 4 Geometry: GEANT 4 Geometry Horn Field Simulation: Horn Field Simulation Horn provides a ×7 increase in the flux and it is therefore necessary to check the motion of charged particles in its magnetic field. Horn field was mapped during testing: 300 positions between inner and outer conductor were mapped. G4 results have been checked, and agree, with a standalone calculation based on the CERNLIB routine DRKNYS (numerical integration routine). G4 Neutrino Flux Predictions: G4 Neutrino Flux Predictions E910 Data: E910 Data Data taken on Au, Cu, Pb, U and Be. Be data taken at momenta of 17.5, 12.3 and 6.4GeV. About 1M events at 12.3GeV. Unfortunately only about 5k events at 6.4GeV. Currently analyzing 12.3 and 6.4GeV data. Initial Sanford-Wang parameterization results look encouraging. HARP (PS214) Data: HARP (PS214) Data Secondary particle production from 8 GeV protons on an actual MiniBooNE target has been measured at HARP. Over 5 million interactions have been recorded. Analysis of data has started. Detector Response: Detector Response NUANCE Monte Carlo used to model particle production in the MiniBooNE detector. BooDetMC used to simulate detector response (GEANT 3 based). Uncertainties associated with each of these. Slide26: Abundance ~40%. Simple topology. Kinematics give Eν and Q2 from Eμ and Θμ. CC νμ Quasi-elastic data Slide27: Yellow band: Monte Carlo with current uncertainties from flux prediction. σCCQE optical properties. CC νμ Quasi-elastic preliminary Selection based on PMT hit topology and timing. Variables combined in a Fisher discriminant, yielding ~88% purity in remaining dataset. Data and MC relatively normalized. Slide28: <10% for Eν>800 MeV CC νμ Quasi-elastic preliminary CC νμ energy resolution. Resistive Wall Monitor: Resistive Wall Monitor Utilizing RWM Timing: Utilizing RWM Timing The goal is to combine the RWM bunch timing with the reconstructed event time in the detector to identify different classes of events. Given that: all mesons do not travel at the same speed. prompt detection of interaction does not always occur. The timing distributions of events with respect to the beam may vary for different event samples. Intrinsic smearing and resolutions may be a problem to achieve powerful discrimination. The RF Bucket Structure: The RF Bucket Structure t1 and t2 are the midpoints to adjacent buckets. unofficial Muon Sample Example: Muon Sample Example unofficial Conclusions: Conclusions Lots of work ongoing on the neutrino beam simulation. Shape agreement between data and MC is reasonable. E910 and especially HARP data should provide an accurate description of target meson production. n Flux at the Detector: n Flux at the Detector preliminary Pion contribution from JAM S-W parameterization. MARS/GFLUKA for kaon contribution.