PPFX Implementation in DUNE

Total Page:16

File Type:pdf, Size:1020Kb

PPFX Implementation in DUNE PPFX Implementation in DUNE Amit Bashyal (Oregon State University) On behalf of Deep Underground Neutrino Experiment (DUNE) Collaboration 1 Deep Underground Neutrino Experiment (DUNE) • DUNE is a future long baseline neutrino experiment • Neutrino oscillation studies to test CP violations in lepton sector and mass ordering • Near Detector will be at 574 m from the start of first focusing horn • Far Detector at 1300 Km in Sanford, South DaKota 2 DUNE Beamline (Reference) Simulation starts from proton beam hitting the target to neutrino production Magnetic horns to focus pions and kaons • Proton Beam hits the target • Charged pions and kaons are Horn 2 produced which in turn are focused Horn 1 by magnetic horns Proton 200 meters long Beam Decay Pipe • 200 meters long decay pipe to let focused pions and kaons decay to Target produce neutrinos 3 DUNE Beamline (Reference & Optimized) Horn C Horn B Horn A Horn 1 Horn 2 Beam/Parameters Reference Optimized Target 1 meter graphite 2 meter graphite Nominal Horns 2 horn (Numi Style) 3 Horn (Ideal, no Optimized Eng. Constraints) Current 230 KA 298 KA Proton Energy 120 GeV 120 GeV 4 DUNE Beam Simulation • LBNF beam line (g4lbnf) written with GEANT4 pacKage • Detailed simulation of particle production, transportation and decay leading to the neutrino flux production • Produced neutrinos are projected at the Far and Near Detector locations for physics studies. 5 Numu Flux at Near Detector ×10−3 0.35 Reference Beam/Parameters Reference Optimized Optimized 0.3 Target 1 meter graphite 2 meter graphite 0.25 Horns 2 horn (Numi Style) 3 Horn (Ideal, no / POT 2 Eng. Constraints) 0.2 Current 230 KA 298 KA s / GeV m 0.15µ ν Proton Energy 120 GeV 120 GeV 0.1 Unosc 0.05 0 0 2 4 6 8 10 12 14 16 18 20 νµ Energy (GeV) 6 Neutrino Flux Prediction Business Neutrino Flux Prediction Business Near/Far Flux And Their Systematics in Correlation the neutrino Flux Ratio Method Matrix Method Focusing Hadron Production It’s a BOTTOM TOP BUSINESS… 7 Neutrino Flux Prediction Business Neutrino Flux Prediction Business Near/Far Flux And Their Systematics in Correlation the neutrino Flux Ratio Method Matrix Method Focusing Hadron Production • Correlated because neutrino flux comes from • Uncertainties in beamline parametersàHorn same hadron hose. position, current, target position, number of • Complex correlation because of detector protons hitting the target etc. locations and beamline geometry 8 Uncertainties from Hadron Production Accurate neutrino flux prediction relies on detailed modeling and understanding of processes starting from primary proton on carbon interaction leading to neutrino production Y Primary X Proton Primary proton hits the Secondary proton re-interacts A pion is target and produces X to produces Y produced Pion is focused by Pion decays to Magnetic horn • Simulated neutrino flux relies on hadronicmodels used in simulation neutrino (QGSP_BERT,FTFP_BERT) • Significant disagreement with real data • Constrain the hadron production models by external data 9 PPFX……Finally • An experiment independent neutrino flux determination pacKage for the NuMI beam* • Correction for hadron production uncertainties using existing thin target data sets** • Developed by Leo Aliaga for the MINERvA collaboration • Currently used by NoVA as well *L. Aliaga Soplin, Neutrino Flux Prediction for the NuMI Beam, Phys. Rev. D 94, 092005 (2016) ** Data set names are listed in the backup slide 10 How PPFX Works? Coverage of interaction by Existing Data sets Simulation Full Neutrino For Ancestry Each interaction in an ancestry • Direct Coverage • Coverage By Extension • No Coverage at all *Coverage by Extension of Data Sets Extend the coverage for interactions that are not covered directly wherever possible *No Coverage at All Apply uncertainties based on best estimation from Full ancestry of a neutrino event (from primary proton current physics models if an interaction is not covered hitting target to neutrino production) directly or indirectly 11 Neutrino Ancestry and Hadronic Interaction in DUNE Flux Interactions coverage by Reweighters Total νµ flux at near detector • To apply the constraints from Hadron production ×10−12 nu_flux_ancestry_7 2.5 ν νµ flux at near detector for ancestry 3 Entries 9427776 Thin Taget Data sets: ν flux at near detector for ancestry 4 µ Mean 3.053 Total Absorption 4 ν flux at nearStd detector Dev for ancestry 1.59 5 − • Need to understand the ancestry of the µ 10 Target Absorption 2 νµ flux at near detector for ancestry 6 pC-->π X pC-->KX neutrino Events per ND nC-->π X • Ancestry 3: pàXà� pC-->nucleonX 1.5 −5 Weighted Neutrino Flux 10 meson inc. • Ancestry 4: pàXàYà � nucleon-A • And so on 1 10−6 • Need to categorize interactions based on 0.5 coverage by hadron production data set 0 10−7 0 1 2 3 4 5 6 7 8 9 10 −100 −50 0 50 100 150 200 250 ν Energy(GeV) Z cm DUNE neutrino flux at ND for 80 Hadron production location and GeV proton beam reference design coverage by ppfx reweighters as a function of ancestry length (not a stacKed plot) 12 How Uncertainties are Categorized 1 1. Total Hadron Production Interactions 2 2. Interactions (excluding 8. interactions) not covered by any of the beloW categories. 3 3. Pion production in proton Carbon Interaction 4 4. Kaon production in proton Carbon Interaction 5 5. Pion production in neutron Carbon Interaction 6 6. Nucleon production in proton Carbon Interaction 7 7. Meson incident Interactions 8 8. Nucleon Incident interactions not covered by any data 2 contains the interactions 3,4,5,6,7,9 and 10 9 9. Absorption outside the target category interactions that are not covered by 10 10. Absorption inside the target thin target data. 13 How Uncertainties are Categorized 1 2 Hadron Production 3 4 Based on pC Thin Target Data 5 6 Quasi elastic interactions, interactions covered by material 7 extensions and interactions outside the range of thin target data sets 8 9 Meson Incidents have large 10 uncertainties 14 How Uncertainties are Categorized 1 2 Attenuation 3 • When a particle traverses through the volume, correction is: � �(� 0 � ) ' � ���� �� 4 • � � = � � [1] 5 • When an interaction happens inside a volume: �� �(����� 0 ���) 6 ����� ' • � � = � � [1] ��� 7 • Here: 8 • C(r ) is the central value correction 9 • �5 is the number of atoms with atomic number A seen by the particle when it traverses the volume 10 15 Interactions Per Near Detector Neutrino Beam/Parameters Reference Optimized total total h_aveint_vs_enu_tot h_aveint_vs_enu_tot 2.5 2.5 Total HP Entries 7976 Total HP Entries 9565 pC-->π X pC-->π X Mean 18.52 Mean 18.14 pC-->KX pC-->KX Std Dev 11.61 Std Dev 11.35Target 1 meter graphite 2 meter graphite nC-->π X nC-->π X 2 2 pC-->nucleonX pC-->nucleonX meson inc. meson inc. nucloen-A Horns 2 horn (Numi Style) 3 Horn (Ideal, no nucloen-A others Eng. Constraints) others 1.5 number of interactions 1.5 number of interactions Current 230 KA 298 KA 1 1 Proton Energy 120 GeV 120 GeV 0.5 0.5 Number of interactions per near detector neutrino covered by various ppfx reweighters 0 0 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 neutrino energy (GeV) neutrino energy (GeV) for 2 different beamline design Reference: 120 GeV Optimized: 120 GeV 16 Fractional Uncertainties DUNE Reference Beam Fractional Uncertainty DUNE Optimized Beam Fractional Uncertainty 0.2 0.2 Total HP Total HP others others 0.18 0.18 pC-->π X pC-->π X pC-->KX pC-->KX 0.16 0.16 Optimized nC-->π X nC-->π X pC-->nucleonX pC-->nucleonX 120 GeV 0.14 Reference 0.14 meson inc. meson inc. nucleon-A nucleon-A 0.12Fractional Uncertainty 120 GeV 0.12Fractional Uncertainty other abs. other abs. Target Absorption Target Absorption 0.1 0.1 0.08 0.08 0.06 0.06 0.04 0.04 0.02 0.02 0 0 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 12 14 16 18 20 νµ Energy (GeV) νµ Energy (GeV) 17 Fractional Uncertainties others Total HP meson inc. 0.022 Reference Reference 0.07 0.02 Optimized Optimized Reference 0.018 0.06 0.12 0.016 0.05 0.014 Optimized 0.012 0.04 0.1 0.01 0.03 0.008 0.006 0.02 0.004 0.08 0.01 0.002 0 0 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 12 14 16 18 20 Target Absorption 0.06 nucloen-A 0.07 Reference 0.07 Reference 0.06 Optimized 0.04 0.06 Optimized 0.05 0.05 0.04 0.04 0.02 0.03 0.03 0.02 0.02 0 0 2 4 6 8 10 12 14 16 18 20 0.01 0.01 0 0 0 2 4 6 8 10 12 14 16 18 20 0 2 4 6 8 10 12 14 16 18 20 18 Summary • PPFX was successfully adapted for the DUNE • Overall uncertainty for both reference and optimized design is below 12% in the region of interest. • Deliverables • Evaluated apriori flux uncertainties • Flux error matrix based on simulated DUNE flux (Laura Fields) delivered to the Near Detector TasK Force • Infrastructure is present in the current DUNE beam simulation software for future apriori flux evaluation for optimized designs 19 Back Up Slides 20 Thin Target Data Sets 21.
Recommended publications
  • Neutrino Flux Predictions for Cross Section Measurements Mark Hartz
    Neutrino Flux Predictions for Cross Section Measurements Mark Hartz University of Toronto and York University, Toronto, Ontario Canada Abstract. Experiments that measure neutrino interaction cross sections using accelerator neutrino sources require a prediction of the neutrino flux to extract the interaction cross section from the measured neutrino interaction rate. This article summarizes methods of estimating the neutrino flux using in-situ and ex-situ measurements. The application of these methods by current and recent experiments is discussed. Keywords: Neutrino flux prediction, Hadron production PACS: 14.60.Lm, 24.10.Lx, 13.85.-t INTRODUCTION Modern neutrino oscillation experiments require measurements of the interaction cross section of neutrinos scattering off of nucleons bound in a nucleus. The interaction cross sections of neutrinos of energy O(1) − O(10) GeV are typically measured with muon neutrinos (νµ ) produced at accelerators by colliding a proton beam with a fixed target. Charged mesons produced in the collisions are typically focused by magnetic horns, and a νµ beam is produced, predominantly from the decays of charged pions. Measuring the interaction cross sections of these νµ requires an absolute prediction of the neutrino spectrum that is determined independently of the interaction process being measured. The configurations of beam lines for some current experiments (MINERνA, MininBooNE, T2K) measuring neutrino cross sections are listed in Table 1. All three experiments employ a low Z target that is ∼ 2 interaction lengths long, and at least one magnetic horn to focus the charged mesons that are produced. A number of methods are applied to predict or measure the neutrino flux spectrum for cross section measurements.
    [Show full text]
  • Neutrino Super Beam Based on a Superconducting Proton Linac
    PHYSICAL REVIEW SPECIAL TOPICS - ACCELERATORS AND BEAMS 17, 031001 (2014) Neutrino super beam based on a superconducting proton linac E. Baussan,1 J. Bielski,2 C. Bobeth,1 E. Bouquerel,1 O. Caretta,3 P. Cupial, 4 T.Davenne,3 C. Densham,3 M. Dracos,1 M. Fitton,3 G. Gaudiot,1 M. Kozien,2 L. Lacny,2 B. Lepers,1 A. Longhin,5 P. Loveridge,3 F. Osswald,1 P. Poussot, 1 M. Rooney,3 B. Skoczen,2 B. Szybinski,2 A. Ustrzycka,2 N. Vassilopoulos,1 D. Wilcox,3 A. Wroblewski,2 J. Wurtz,1 V. Zeter, 1 and M. Zito5* 1IPHC, Université de Strasbourg, CNRS/IN2P3, F-67037 Strasbourg, France 2Cracow University of Technology, Warszawska 24 St., 31-155 Krakow, Poland 3STFC Rutherford Appleton Laboratory, OX11 0QX Didcot, United Kingdom 4AGH University of Science and Technology, Krakow, Poland 5Irfu, CEA-Saclay, 91191 Gif-sur-Yvette, France (Received 5 December 2012; published 17 March 2014) We present a new design study of the neutrino Super Beam based on the Superconducting Proton Linac at CERN. This beam is aimed at megaton mass physics, a large water Cherenkov detector, proposed for the Laboratoire Souterrain de Modane in France, with a baseline of 130 km. The aim of this proposed facility is to study CP violation in the neutrino sector. In the study reported here, we have developed the conceptual design of the neutrino beam, especially the target and the magnetic focusing device. Indeed, this beam presents several unprecedented challenges, related to the high primary proton beam power (4 MW), the high repetition rate (50 Hz), and the low kinetic energy of the protons (4.5 GeV).
    [Show full text]
  • Arxiv:Physics/0609129V1
    Accelerator Neutrino Beams Sacha E. Kopp, Department of Physics, University of Texas at Austin Abstract Neutrino beams at from high-energy proton accelerators have been instrumental discovery tools in particle physics. Neutrino beams are derived from the decays of charged π and K mesons, which in turn are created from proton beams striking thick nuclear targets. The precise selection and manipulation of the π/K beam control the energy spectrum and type of neutrino beam. This article describes the physics of particle production in a target and manipulation of the particles to derive a neutrino beam, as well as numerous innovations achieved at past experimental facilities. Contents 1 Introduction 2 2 Accelerator Neutrino Beam Concept 3 3 Production of Hadrons in the Target 6 3.1 Introduction.................................... ..... 6 3.2 HadronProductionExperiments . ........ 11 3.3 Some Parameterizations and Models . ......... 16 4 Focusing of Wide Band Beams 18 4.1 HornFocusing .................................... 18 4.2 Multi-hornSystems............................... ...... 24 4.3 Quadrupole-FocusedBeams . ....... 29 4.4 Otherfocusingsystems. ....... 34 5 Focusing of Narrow-Band Beams 37 5.1 DichromaticBeam ................................. 37 5.2 HornBeamwithPlug ................................ 39 arXiv:physics/0609129v1 [physics.acc-ph] 14 Sep 2006 5.3 HornBeamwithDipole .............................. 39 5.4 Off-AxisNeutrinoBeam ............................. ..... 40 6 Decay Volumes 43 6.1 DecayTube......................................
    [Show full text]
  • Neutrino Induced Neutral Current Single Π0 Production at the Near Detector of the T2K Experiment
    Neutrino induced neutral current single π0 production at the near detector of the T2K experiment Leon James Pickard A thesis submitted to the University of Sheffield for the Degree of Doctor of Philosophy in Physics Supervisor: Prof. Lee F. Thompson July 2016 i ii Abstract T2K is a long baseline neutrino oscillation experiment located at the J-PARC facility in eastern Japan. The neutrino beam has a peak energy of ∼0.60 GeV and is directed 2.5◦ off-axis, passing through the near detector (ND280), 280 m from the source, towards Super-Kamiokande, a 50 kt water Cherenkov detector, 295 km away. One of the main goals of T2K is to measure νµ ! νe oscillations and so determine the value of θ13. The first indication of a non-zero value was found in June 2011 and the first measurement in November 2013. 0 0 The analysis presented in this thesis is a νµ induced neutral current single π (NC1π ) cross-section measurement which utilises the tracking detector region of ND280. This is of importance to T2K as NC1π0 interactions represent the second largest uncertainty in the νe appearance measurement - behind only the intrinsic νe component of the beam. Furthermore, it is also of use to the wider neutrino community as few such measurements exist in the field. Thus, studies of this nature are invaluable in testing and improving cross-section models. This analysis considers 5 distinct measurements with different topologies of interest and compares the total cross-sections, alongside the dσ=dpπ0 and dσ/dcosθπ0 distributions, to the Monte Carlo prediction.
    [Show full text]
  • DUNE Powerpoint Presentation
    Neutrino Oscillations Stefan Söldner-Rembold University of Manchester Academic Training Lecture Programme May 2021 1 Lecture 2 Reactor measurements of θ13 CP violation, and current long-baseline experiments 2 PMNS Matrix solar “reactor” atmospheric • Θ12 and θ23 are large (“maximal” mixing) • Angle θ13 is small and mixes 휈e with 휈3 • CPV term (δ) ∝ θ13 2 • Look for 휈e mixing driven by Δm 32 3 Daya Bay reactor 4 “Reactor” Oscillations “Survival probability” for anti-휈e from the reactor (E ≈ 3 MeV) Daya Bay: Near Far Juno KamLAND J. Ling, Neutrino 2020 5 Daya Bay Layout 6 Daya Bay detectors Each of the 8 detector is 20 tons. Photomultiplier tubes Inverse 훽 decay Scintillator, loaded with gadolinium (high neutron capture cross section) Scintillator buffer (no gadolinium) 7 Inner acrylic tank Original θ13 measurements (Far/Near) M.He, NNN 8 θ13 measurement (Daya Bay) 9 PMNS Matrix solar reactor atmospheric • Small angle θ13 mixes 휈e with 휈3 2 • Look for 휈e mixing driven by Δm 32 • Reactor: anti-휈e disappearance • Accelerator: 휈e appearance in 휈휇 beam → sensitive to θ13 and 훿 10 CKM vs PMNS The CKM matrix is almost diagonal, while the PMNS matrix is almost uniform. 11 Matter and Anti-matter Paul Dirac Dirac equation predicts anti-particle states (1928) Positron discovered by C.D. Anderson in 1932 12 Matter-antimatter asymmetry (“CP violation”) • A tiny (≈10-10) asymmetry between particle and anti-particles led to our matter dominated universe • One of the conditions for this asymmetry is violation of CP symmetry • The observation of CP violation involving neutrinos could provide support for a theory called Leptogenesis 1.
    [Show full text]
  • History of Accelerator Neutrino Beams
    History of accelerator neutrino beams Ubaldo Dore1, Pier Loverre1;2, and Lucio Ludovici2;a 1 Dipartimento di Fisica, Universit`adi Roma Sapienza, P.le A.Moro 2, 00185 Rome Italy 2 INFN, Sezione di Roma Sapienza, P.le A.Moro 2, 00185 Rome Italy Abstract. Neutrino beams obtained from proton accelerators were first operated in 1962. Since then, neutrino beams have been intensively used in particle physics and evolved in many different ways. We describe the characteristics of various neutrino beams, relating them to the historical development of the physics studies and discoveries. We also discuss some of the ideas still under consideration for future neutrino beams. 1 Introduction In 1956 the detection by Reines and Cowan [Cowan 1956] at a nuclear reactor proved that the "desperate remedy" proposed by Pauli [Pauli 1930] more than a quarter of a century before, was a real sub-atomic particle. The particle postulated by Pauli to save the principle of energy conservation in beta decays, was named by Fermi neutrino and turned out to be a central ingredient of his new theory of weak interactions [Fermi 1933]1. Three years later in a famous paper Bruno Pontecorvo discussed the hypothesis that neutrinos emitted in the decay of charged pions were different from the ones produced in beta decays [Pontecorvo 1959]. The paper considered specific experiments to test this hypothesis, proposing also to use neutrinos from decay in flight of pions produced by accelerated protons hitting a target. Independently, in 1960 Mel Schwartz published the first realistic scheme of a neu- trino beam for the study of the weak interaction [Schwartz 1960].
    [Show full text]
  • D Harris, Constraining the Numi Neutrino Beam [PDF]
    Constraining the NuMI Flux Deborah Harris Fermilab NuINT 2014 May 22, 2014 With thanks to: Bob Zwaska, Jeff Nelson, Anne Norrick, Leo Aliaga, Mike Kordosky Outline • Introduction to NuMI Beamline • From Indirect to Direct Constraints – Monte Carlo Predictions – Hadron Production Constraints – In Situ Muon Flux Constraints – Neutrino Flux Measurements • Neutrino-electron Scattering • “Low-Nu” technique – Alternate Beam Configuration Data • Scorecard 22 May 2014 Deborah Harris, Constraining the NUMI Flux 2 The best way to constrain? 22 May 2014 Deborah Harris, Constraining the NUMI Flux 3 Simplifying the problem… • Protons strike target, make pions and kaons – Need to understand hadron production for 120GeV protons on 2 interaction lengths of graphite • Pions and kaons focused by magnetic horn – Need to understand and simulate focusing elements • Pions and kaons decay in beamline – Those pions and kaons often reinteract in the beamline, need to understand tertiary production (production on Al, etc.) 22 May 2014 Deborah Harris, Constraining the NUMI Flux 4 Fluxes in NuMI Beamline • Low Energy Run – 2005 through 2012 – Neutrinos and Antineutrinos both – 95cm graphite target – “Moveable” target – 12x1020 protons on target • Medium Energy Run – September 2013 and beyond – Neutrinos and Antineutrinos planned – 95cm graphite target – Non-moveable target – 2x1020 protons on target and counting… 22 May 2014 Deborah Harris, Constraining the NUMI Flux 5 Near Flux, Far Flux • Two-detector experiment mantra: “ Φ and σ uncertainties cancel…” • Far and
    [Show full text]
  • Three-Flavor Oscillations with Accelerator Neutrino Beams
    universe Review Three-Flavor Oscillations with Accelerator Neutrino Beams Mauro Mezzetto 1 and Francesco Terranova 2,3,* 1 INFN sez. di Padova, Via F. Marzolo 8, I-35131 Padova, Italy; [email protected] 2 Department of Physics, Universe of Milano-Bicocca, Piazza della Scienza 3, I-20126 Milano, Italy 3 INFN sez. di Milano-Bicocca, Piazza della Scienza 3, I-20126 Milano, Italy * Correspondence: [email protected] Received: 19 December 2019; Accepted: 8 February 2020; Published: 11 February 2020 Abstract: The three-flavor neutrino oscillation paradigm is well established in particle physics thanks to the crucial contribution of accelerator neutrino beam experiments. In this paper, we review the most important contributions of these experiments to the physics of massive neutrinos after the discovery of q13 and future perspectives in such a lively field of research. Special emphasis is given to the technical challenges of high power beams and the oscillation results of T2K, OPERA, ICARUS, and NOnA . We discuss in detail the role of accelerator neutrino experiments in the precision era of neutrino physics in view of DUNE and Hyper-Kamiokande, the program of systematic uncertainty reduction and the development of new beam facilities. Keywords: neutrino oscillations; accelerator neutrino beams; neutrino detectors 1. Introduction High intensity neutrino beams at energies above 100 MeV are produced at proton accelerators since 1962 and played a key role in the foundation of the electroweak theory and the study of nuclear structure. Unlike other neutrino sources, they provide an unprecedented level of control of the flavor at source, flux and energy, which has been prominent in confirming the very existence of neutrino oscillations and measuring with high precision the oscillation parameters.
    [Show full text]
  • Vallari-Zoya-December-2018.Pdf
    Measurement of Single π0 Production in Neutral Current Neutrino Interactions on Water at the Near Detector of the T2K experiment A Dissertation presented by Zoya Vallari to The Graduate School in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Physics and Astronomy Stony Brook University December 2018 Stony Brook University The Graduate School Zoya Vallari We, the dissertation committee for the above candidate for the Doctor of Philosophy degree, hereby recommend acceptance of this dissertation Chang Kee Jung - Dissertation Advisor Professor, Physics and Astronomy Rouven Essig - Chairperson of Defense Associate Professor, Physics and Astronomy Joanna Kiryluk Associate Professor, Physics and Astronomy Clark McGrew Associate Professor, Physics and Astronomy Xin Qian Physicist, Brookhaven National Laboratory This dissertation is accepted by the Graduate School Dean of the Graduate School ii Abstract of the Dissertation Measurement of Single π0 Production in Neutral Current Neutrino Interactions on Water at the Near Detector of the T2K experiment by Zoya Vallari Doctor of Philosophy in Physics and Astronomy Stony Brook University 2018 T2K is a long baseline neutrino oscillation experiment located in Japan. It was built mainly to detect muon neutrino to electron neutrino oscillation and to measure the mixing angle θ13 of the PMNS matrix, along with the precision measurement of θ23 and mass differences. A νµ beam is produced at the Japan Proton Accelerator Research Complex (J-PARC) in Tokai and travels to the far detector in Kamioka, Japan. There is an ensemble of detectors at 280 m downstream of the target that form the near detector. Super-Kamiokande, a water Cherenkov detector, located 295 km away from the target serves as the far detector.
    [Show full text]
  • Neutrino-Electron Scattering in Minerνa for Constraining the Numi Neutrino Flux
    Neutrino-Electron Scattering in MINERνA for Constraining the NuMI Neutrino Flux by Jaewon Park Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Supervised by Professor Kevin McFarland Department of Physics and Astronomy Arts, Sciences and Engineering School of Arts and Sciences University of Rochester Rochester, New York 2013 ii Biographical Sketch The author He attended Korea University at Seoul, and graduated with a Bachelor of Science degree in physics. He received a Master of Science degree from Korea University in 2003. He began doctoral studies in elementary particle physics at the University of Rochester in 2004. He received a master of arts from the University of Rochester in 2006. He started his research in MINERvA experiment under the supervision of Prof. Kevin McFarland. He has been involved in various stages of the experiment: detector R&D, construction, data taking, calibration, event reconstruction and data analysis. iii Abstract Neutrino-electron elastic scattering is used as a reference process to constrain the neutrino flux at the Main Injector (NuMI) beam observed by the MINERvA experi- ment. Prediction of the neutrino flux at accelerator experiments from other methods has a large uncertainty, and this uncertainty degrades measurements of neutrino os- cillations and neutrino cross-sections. Neutrino-electron elastic scattering is a rare process, but its cross-section is precisely known. With a sample corresponding to 3:5 × 1020 protons on target in the NuMI low-energy neutrino beam, a sample of 120 νe− ! νe− candidate events were observed with a predicted background of ≈ 30 events. This results in a flux constraint with 13% fractional precision, which is comparable to the uncertainty in other prediction methods.
    [Show full text]