How to Discern a Physical Effect from Background Noise: the Discovery of Weak Neutral Currents
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Sensitivity Study and First Prototype Tests for the CHIPS Neutrino
Sensitivity study and first prototype tests for the CHIPS neutrino detector R&D program Maciej Marek Pfützner University College London Submitted to University College London in fulfilment of the requirements for the award of the degree of Doctor of Philosophy July 20, 2018 1 2 Declaration I, Maciej Marek Pfützner confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. Maciej Pfützner 3 4 Abstract CHIPS (CHerenkov detectors In mine PitS) is an R&D project aiming to develop novel cost-effective detectors for long baseline neutrino oscillation experiments. Water Cherenkov detector modules will be submerged in an existing lake in the path of an accelerator neutrino beam, eliminating the need for expensive excavation. In a staged approach, the first detectors will be deployed in a flooded mine pit in northern Minnesota, 7 mrad off-axis from the existing NuMI beam. A small proof-of-principle model (CHIPS-M) has already been tested and the first stage of a fully functional 10 kt module (CHIPS-10) is planned for 2018. The main physics aim is to measure the CP-violating neutrino mixing phase (δCP). A sensitivity study was performed with the GLoBES package, using results from a dedicated detector simulation and a preliminary reconstruction algorithm. The predicted physics reach of CHIPS-10 and potential bigger modules is presented and compared with currently running experiments and future projects. One of the instruments submerged on board CHIPS-M in autumn 2015 was a prototype detection unit, constructed at Nikhef. -
A Mislivec, Minerva Coherent
Charged Current Coherent Pion Production in MINERνA Aaron Mislivec University of Rochester w/ Aaron Higuera Outline • Motivation • MINERνA Detector and Kinematics Reconstruction • Event Selection • Background Tuning • Contribution from Diffractive Scattering off Hydrogen • Systematics • Cross Sections Aaron Mislivec, University of Rochester NuInt14 2 K. HIRAIDE et al. PHYSICAL REVIEW D 78, 112004 (2008) 100 TABLE III. Event selection summary for the MRD-stopped DATA charged current coherent pion sample. CC coherent π Event selection Data MC Coherent % CC resonant π Signal BG Efficiency Other Generated in SciBar fid.vol. 1939 156 766 100% CC QE 50 SciBar-MRD matched 30 337 978 29 359 50.4% MRD-stopped 21 762 715 20 437 36.9% two-track 5939 358 6073 18.5% Entries / 5 degrees Particle ID (" %) 2255 292 2336 15.1% Vertex activityþ cut 887 264 961 13.6% CCQE rejection 682 241 709 12.4% 0 0 20 40 60 80 100 120 140 160 180 Pion track direction cut 425 233 451 12.0% Reconstructed Q2 cut 247 201 228 10.4% ∆θp (degrees) FIG. 11 (color online). Á for the " % events in the MRD p þ stopped sample after fitting. which the track angle of the pion candidate with respect to the beam direction is less than 90 degrees are selected. Figure 13 shows the reconstructed Q2 distribution for the " % events after the pion track direction cut. Althoughþ a charged current quasielastic interaction is as- DATA 80 sumed, the Q2 of charged current coherent pion events is CC coherent π reconstructed with a resolution of 0:016 GeV=c 2 and a CC resonant π 2 ð Þ 60 shift of 0:024 GeV=c according to the MC simulation. -
12 from Neutral Currents to Weak Vector Bosons
12 From neutral currents to weak vector bosons The unification of weak and electromagnetic interactions, 1973{1987 Fermi's theory of weak interactions survived nearly unaltered over the years. Its basic structure was slightly modified by the addition of Gamow-Teller terms and finally by the determination of the V-A form, but its essence as a four fermion interaction remained. Fermi's original insight was based on the analogy with elec- tromagnetism; from the start it was clear that there might be vector particles transmitting the weak force the way the photon transmits the electromagnetic force. Since the weak interaction was of short range, the vector particle would have to be heavy, and since beta decay changed nuclear charge, the particle would have to carry charge. The weak (or W) boson was the object of many searches. No evidence of the W boson was found in the mass region up to 20 GeV. The V-A theory, which was equivalent to a theory with a very heavy W , was a satisfactory description of all weak interaction data. Nevertheless, it was clear that the theory was not complete. As described in Chapter 6, it predicted cross sections at very high energies that violated unitarity, the basic principle that says that the probability for an individual process to occur must be less than or equal to unity. A consequence of unitarity is that the total cross section for a process with 2 angular momentum J can never exceed 4π(2J + 1)=pcm. However, we have seen that neutrino cross sections grow linearly with increasing center of mass energy. -
Discovery of Weak Neutral Currents∗
Discovery of Weak Neutral Currents∗ Dieter Haidt Emeritus at DESY, Hamburg 1 Introduction Following the tradition of previous Neutrino Conferences the opening talk is devoted to a historic event, this year to the epoch-making discovery of Weak Neutral Currents four decades ago. The major laboratories joined in a worldwide effort to investigate this new phenomenon. It resulted in new accelerators and colliders pushing the energy frontier from the GeV to the TeV regime and led to the development of new, almost bubble chamber like, general purpose detectors. While the Gargamelle collaboration consisted of seven european laboratories and was with nearly 60 members one of the biggest collaborations at the time, the LHC collaborations by now have grown to 3000 members coming from all parts in the world. Indeed, High Energy Physics is now done on a worldwide level thanks to net working and fast communications. It seems hardly imaginable that 40 years ago there was no handy, no world wide web, no laptop, no email and program codes had to be punched on cards. Before describing the discovery of weak neutral currents as such and the cir- cumstances how it came about a brief look at the past four decades is anticipated. The history of weak neutral currents has been told in numerous reviews and spe- cialized conferences. Neutral currents have since long a firm place in textbooks. The literature is correspondingly rich - just to point out a few references [1, 2, 3, 4]. 2 Four decades Figure 1 sketches the glorious electroweak way originating in the discovery of weak neutral currents by the Gargamelle Collaboration and followed by the series of eminent discoveries. -
Introduction to Subatomic- Particle Spectrometers∗
IIT-CAPP-15/2 Introduction to Subatomic- Particle Spectrometers∗ Daniel M. Kaplan Illinois Institute of Technology Chicago, IL 60616 Charles E. Lane Drexel University Philadelphia, PA 19104 Kenneth S. Nelsony University of Virginia Charlottesville, VA 22901 Abstract An introductory review, suitable for the beginning student of high-energy physics or professionals from other fields who may desire familiarity with subatomic-particle detection techniques. Subatomic-particle fundamentals and the basics of particle in- teractions with matter are summarized, after which we review particle detectors. We conclude with three examples that illustrate the variety of subatomic-particle spectrom- eters and exemplify the combined use of several detection techniques to characterize interaction events more-or-less completely. arXiv:physics/9805026v3 [physics.ins-det] 17 Jul 2015 ∗To appear in the Wiley Encyclopedia of Electrical and Electronics Engineering. yNow at Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723. 1 Contents 1 Introduction 5 2 Overview of Subatomic Particles 5 2.1 Leptons, Hadrons, Gauge and Higgs Bosons . 5 2.2 Neutrinos . 6 2.3 Quarks . 8 3 Overview of Particle Detection 9 3.1 Position Measurement: Hodoscopes and Telescopes . 9 3.2 Momentum and Energy Measurement . 9 3.2.1 Magnetic Spectrometry . 9 3.2.2 Calorimeters . 10 3.3 Particle Identification . 10 3.3.1 Calorimetric Electron (and Photon) Identification . 10 3.3.2 Muon Identification . 11 3.3.3 Time of Flight and Ionization . 11 3.3.4 Cherenkov Detectors . 11 3.3.5 Transition-Radiation Detectors . 12 3.4 Neutrino Detection . 12 3.4.1 Reactor Neutrinos . 12 3.4.2 Detection of High Energy Neutrinos . -
The History of Neutrinos, 1930 − 1985
The History of Neutrinos, 1930 − 1985. What have we Learned About Neutrinos? What have we Learned Using Neutrinos? J. Steinberger Prepared for “25th International Conference On Neutrino Physics and Astrophysics”, Kyoto (Japan), June 2012 1 2 3 4 The detector of the experiment of Conversi, Pancini and Piccioni, 1946, 5 which showed that the mesotron is not the Yukawa particle. Detector with 80 Geiger counters. The muon decay spectrum is continuous. My thesis experiment, under Fermi, which showed that the muon decays into two neutral particles, plus the electron. Fermi, myself and others, in 1954, at a summer school in Varenna, lake Como, a few months before Fermi’s untimely disappearance. 6 Demonstration of the Neutrino In 1956 Cowan and Reines detected antineutrinos from a nuclear reactor, reacting with protons in liquid scintillator which also contained cadmium, observing the positron as well as the scattering of the neutron on cadmium. 7 The Electron and Muon Neutrinos are Different. 1. G. Feinberg, 1958. 2. B. Pontecorvo, 1959. 3. M. Schwartz (T.D. Lee), 1959 4. Higher energy accelerators, Courant, Livingston and Snyder. Pontecorvo 8 9 A C B D Spark chamber and counter arrangement. A are triggering counters, Energy spectra of neutrinos B, C and D are anticoincidence counters from pion and kaon decays. 10 Event with penetrating muon and hadron shower 11 The group of the 2nd neutrino experiment in 1962: J.S., Goulianos, Gaillard, Mistry, Danby, technician whose name I have forgotten, Lederman and Schwartz. 12 Same group, 26 years later, at Nobel ceremony in Stockholm. 13 Discovery of partons, nucleon structure, scaling, in deep inelastic scattering of electrons on protons at SLAC in 1969. -
Lesson 46: Cloud & Bubble Chambers
Lesson 46: Cloud & Bubble Chambers Imagine you're on a really stupid game show where they put a whole bunch of ping pong balls on the floor, turn off the lights, and then send you in to count them. How would you do it? • I'm thinking that your only chance is to get down on your hands and knees and try to touch them around you. • One of the problems is that in the very act of counting them (by reaching out), you change them by pushing them around, maybe even missing some of them. This is kind of the same problem that subatomic physicists have. They have to reach around “in the dark” to measure something that they can't see. • The amazing part is that methods have been developed to do this, and actually do it accurately. • This is the beginning of our journey into the modern subatomic realm of physics. Cloud Chambers In 1894 the Scottish physicist Charles Wilson was interested in the odd shadows that can sometimes be formed on cloud tops by mountain climbers (called Brocken Spectre). • To be able to study this further, he came up with a way water to build a device called a cloud chamber that would droplets allow him to make his own mini-clouds inside a glass chamber. ◦ To be able to do this he made his device so that he could keep the air inside supersaturated with water. ▪ Air can usually only hold a certain amount of path of vapour. Supersaturated means the air was charged particle holding more vapour than it would normally be Illustration 1: Water droplets condense able to at that pressure and temperature. -
Measurement of the + ̅ Charged Current Inclusive Cross Section
Measurement of the �! + �!̅ Charged Current Inclusive Cross Section on Argon in MicroBooNE Krishan Mistry on behalf of the MicroBooNE Collaboration 15 March 2021 New Directions in Neutrino-Nucleus Scattering (NDNN) NuSTEC Workshop ICARUS T600 MicroBooNE SBND Importance of the �!-Ar cross section • MicroBooNE + SBN Program + DUNE ⇥ Employ Liquid Argon Time Projection Chambers (LArTPCs) arXiv:1503.01520 [physics.ins-det] • Primary signal channel for these experiments is �!– Ar CC interactions arXiv:2002.03005 [hep-ex] 15 March 2021 K Mistry 2 Building a Picture of �! Interactions ArgoNeuT is the first A handful of measurements measurement made on on other nuclei in the argon hundred MeV to GeV range ⇥ Sample of 13 selected events Nuclear Physics B 133, 205 – 219 (1978) Phys. Rev. D 102, 011101(R) (2020) ⇥ Gargamelle Phys. Rev. Lett. 113, 241803 (2014) ⇥ Phys. Rev. D 91, 112010 (2015) T2K J. High Energ. Phys. 2020, 114 (2020) ⇥ MINER�A Phys. Rev. Lett. 116, 081802 (2016) !! " !! " Argon Other 15 March 2021 K Mistry 3 What are we measuring? ! /!̅ " # • Total �!+ �!̅ Charged Current (CC) ! ! $ /$ inclusive cross section • Signature: the neutrino event ? contains at least one electron-liKe shower Ar ⇥ No requirements on the presence (or absence) of any additional particle ⇥ Do not differentiate between �! and �!̅ Inclusive channel is the most straightforward channel to compare to predictions 15 March 2021 K Mistry 4 MicroBooNE • Measurement is performed • Features of a LArTPC using the MicroBooNE detector: LArTPC ⇥ Precise calorimetry ⇥ 4� -
Super-Kamiokande Atmospheric Neutrino Analysis of Matter-Dependent Neutrino Oscillation Models
Super-Kamiokande Atmospheric Neutrino Analysis of Matter-Dependent Neutrino Oscillation Models Kiyoshi Keola Shiraishi A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2006 Program Authorized to Offer Degree: Physics University of Washington Graduate School This is to certify that I have examined this copy of a doctoral dissertation by Kiyoshi Keola Shiraishi and have found that it is complete and satisfactory in all respects, and that any and all revisions required by the final examining committee have been made. Chair of the Supervisory Committee: R. Jeffrey Wilkes Reading Committee: R. Jeffrey Wilkes Thompson Burnett Ann Nelson Cecilia Lunardini Date: In presenting this dissertation in partial fulfillment of the requirements for the doctoral degree at the University of Washington, I agree that the Library shall make its copies freely available for inspection. I further agree that extensive copying of this dissertation is allowable only for scholarly purposes, consistent with “fair use” as prescribed in the U.S. Copyright Law. Requests for copying or reproduction of this dissertation may be referred to Proquest Information and Learning, 300 North Zeeb Road, Ann Arbor, MI 48106-1346, 1-800-521-0600, to whom the author has granted “the right to reproduce and sell (a) copies of the manuscript in microform and/or (b) printed copies of the manuscript made from microform.” Signature Date University of Washington Abstract Super-Kamiokande Atmospheric Neutrino Analysis of Matter-Dependent Neutrino Oscillation Models Kiyoshi Keola Shiraishi Chair of the Supervisory Committee: Professor R. Jeffrey Wilkes Physics Current data finds that the atmospheric neutrino anomaly is best explained with ν µ − ντ neutrino oscillations. -
Measurement of Neutrino-Nucleon Neutral-Current Elastic Scattering Cross-Section at Sciboone
Measurement of Neutrino-Nucleon Neutral-Current Elastic Scattering Cross-section at SciBooNE Hideyuki Takei Thesis submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Science at Tokyo Institute of Technology February, 2009 2 Abstract In this thesis, results of neutrino-nucleon neutral current (NC) elastic scattering analysis are presented. Neutrinos interact with other particles only with weak force. Measure- ment of cross-section for neutrino-nucleon reactions at various neutrino en- ergy are important for the study of nucleon structure. It also provides data to be used for beam flux monitor in neutrino oscillation experiments. The cross-section for neutrino-nucleon NC elastic scattering contains the 2 axial vector form factor GA(Q ) as well as electromagnetic form factors unlike electromagnetic interaction. GA is propotional to strange part of nucleon spin (∆ s) in Q2 → 0 limit. Measurement of NC elastic cross-section with smaller Q2 enables us to access ∆ s. NC elastic cross-sections of neutrino- nucleon and antineutrino-nucleon were measured earlier by E734 experiment at Brookheaven National Laboratory (BNL) in 1987. In this experiment, cross-sections were measured in Q2 > 0.4 GeV 2 region. Result from this experiment was the only published data for NC elastic scattering cross-section published before our experiment. SciBooNE is an experiment for the measurement of neutrino-nucleon scat- tering cross-secitons using Booster Neutrino Beam (BNB) at FNAL. BNB has energy peak at 0.7 GeV. In this energy region, NC elastic scattering, charged current elastic scattering, charged current pion production, and neutral cur- rent pion production are the major reaction branches. -
PDF) Submittals Are Preferred) and Information Particle and Astroparticle Physics As Well As Accelerator Physics
CERNNovember/December 2019 cerncourier.com COURIERReporting on international high-energy physics WELCOME CERN Courier – digital edition Welcome to the digital edition of the November/December 2019 issue of CERN Courier. The Extremely Large Telescope, adorning the cover of this issue, is due to EXTREMELY record first light in 2025 and will outperform existing telescopes by orders of magnitude. It is one of several large instruments to look forward to in the decade ahead, which will also see the start of high-luminosity LHC operations. LARGE TELESCOPE As the 2020s gets under way, the Courier will be reviewing the LHC’s 10-year physics programme so far, as well as charting progress in other domains. In the meantime, enjoy news of KATRIN’s first limit on the neutrino mass (p7), a summary of the recently published European strategy briefing book (p8), the genesis of a hadron-therapy centre in Southeast Europe (p9), and dispatches from the most interesting recent conferences (pp19—23). CLIC’s status and future (p41), the abstract world of gauge–gravity duality (p44), France’s particle-physics origins (p37) and CERN’s open days (p32) are other highlights from this last issue of the decade. Enjoy! To sign up to the new-issue alert, please visit: http://comms.iop.org/k/iop/cerncourier To subscribe to the magazine, please visit: https://cerncourier.com/p/about-cern-courier KATRIN weighs in on neutrinos Maldacena on the gauge–gravity dual FPGAs that speak your language EDITOR: MATTHEW CHALMERS, CERN DIGITAL EDITION CREATED BY IOP PUBLISHING CCNovDec19_Cover_v1.indd 1 29/10/2019 15:41 CERNCOURIER www. -
01Ii Beam Line
STA N FO RD LIN EA R A C C ELERA TO R C EN TER Fall 2001, Vol. 31, No. 3 CONTENTS A PERIODICAL OF PARTICLE PHYSICS FALL 2001 VOL. 31, NUMBER 3 Guest Editor MICHAEL RIORDAN Editors RENE DONALDSON, BILL KIRK Contributing Editors GORDON FRASER JUDY JACKSON, AKIHIRO MAKI MICHAEL RIORDAN, PEDRO WALOSCHEK Editorial Advisory Board PATRICIA BURCHAT, DAVID BURKE LANCE DIXON, EDWARD HARTOUNI ABRAHAM SEIDEN, GEORGE SMOOT HERMAN WINICK Illustrations TERRY ANDERSON Distribution CRYSTAL TILGHMAN The Beam Line is published quarterly by the Stanford Linear Accelerator Center, Box 4349, Stanford, CA 94309. Telephone: (650) 926-2585. EMAIL: [email protected] FAX: (650) 926-4500 Issues of the Beam Line are accessible electroni- cally on the World Wide Web at http://www.slac. stanford.edu/pubs/beamline. SLAC is operated by Stanford University under contract with the U.S. Department of Energy. The opinions of the authors do not necessarily reflect the policies of the Stanford Linear Accelerator Center. Cover: The Sudbury Neutrino Observatory detects neutrinos from the sun. This interior view from beneath the detector shows the acrylic vessel containing 1000 tons of heavy water, surrounded by photomultiplier tubes. (Courtesy SNO Collaboration) Printed on recycled paper 2 FOREWORD 32 THE ENIGMATIC WORLD David O. Caldwell OF NEUTRINOS Trying to discern the patterns of neutrino masses and mixing. FEATURES Boris Kayser 42 THE K2K NEUTRINO 4 PAULI’S GHOST EXPERIMENT A seventy-year saga of the conception The world’s first long-baseline and discovery of neutrinos. neutrino experiment is beginning Michael Riordan to produce results. Koichiro Nishikawa & Jeffrey Wilkes 15 MINING SUNSHINE The first results from the Sudbury 50 WHATEVER HAPPENED Neutrino Observatory reveal TO HOT DARK MATTER? the “missing” solar neutrinos.