Jack Steinberger

Total Page:16

File Type:pdf, Size:1020Kb

Jack Steinberger EXPERI ME NTS WIT H HI G H-E NER GY NEUTRI N O BEA MS Nobel Lect ure, Dece mber 8, 1988 b y J ACK STEI NBER GER CE R N, Geneva, S witzerland, and Scuola Nor male Superiore, Pisa, Italy 1. I NTR O D UCTI O N High-energy ne utrino bea ms have fo un d intensive an d varie d a p plication in p arti cl e p h ysi cs e x p eri m e nt ati o n i n t h e l ast d e c a d es. T his r e vi e w is c o n- str ai n e d t o a f e w of t h e m ost fr uitf ul e x a m pl es: t h e dis c o v er y of n e utr al c urrents, the meas ure ment of the Weinberg angle, the st u dy of weak c urre nts a n d t he co nse q ue nt test of t he electro wea k t heor y, t he st u d y of n ucleo n q uark str uct ure, an d the testing of quantu m chro mo dyna mics ( Q C D). Ot her st u dies s uc h as t he pro d uctio n of “ pro m pt” ne utri nos, t he s e ar c h f or fi nit e n e utri n o m ass es a n d n e utri n o os cill ati o ns, t h e s e ar c h f or hea vy le pto ns or ot her ne w particles, or t he meas ure me nt of proto n a n d ne utro n str uct ure f u nctio ns, elastic a n d pse u doelastic cross-sectio ns, a n d ot her excl usive processes, are not disc usse d here. Ne utri no ex peri me nts have bee n p urs ue d vigoro usly at t he Brook have n Natio nal Laboratory, at Fer milab, an d at C E R N. It is fair to say that they have ma de large contrib u- tions to o ur un derstan ding of particle physics. 2. NE UTRI N O BE A MS Present ne utrino bea ms are pro d uce d in fo ur ste ps: i) pro d uction of secon- dar y ha dro ns i n t he collisio n of hi g h-e ner g y proto ns o n a fixe d tar get; ii) mo ment u m (charge) selection an d foc using of the ha drons; iii) passage of t he bea m t hro ug h a n (e vac uate d) decay regio n, lo ng e no ug h to per mit a s ubstantial fraction of the ha drons to decay; iv) absor ption of the re maining h a dr o ns a n d t h e m u o ns t h at ar e pr o d u c e d al o n g wit h t h e ‘ n e utri n os i n a s hiel d of a de q uate t hic k ness. T he t wo-bo d y deca ys an d acc o u nt f or ~ 97 % of t he ne utri no fl ux i n prese nt bea ms. Positive ha drons pro d uce ne utrinos, negative ha drons pro d uce a nti ne utri nos. Fig ures la a n d lb gi ve a n i m pressio n of t he t wo ha dro n bea m-for ming options that are available, si de by si de, at C E R N: a conven- tional, so-calle d narro w-ban d bea m ( N B B), an d an achro matic, Van der Meer horn-foc use d, wi de-ban d bea m ( W B B). The ne utrino s pectra pro- d uce d b y t hese t w o bea ms are ver y differe nt, as s h o w n i n Fi g ure 2. T he 4 8 8 Physics 1988 Fi g ure 1 a Sketch of narro w-band and wide-band neutrino bea m layouts at C E R N, sho wing disposition of pri mary target, focusing ele ments, decay region, shielding, and monitoring de vices. Fi g ur e 1 b Vie w of the neutrino bea m tunnel at the C E R N S P S in 1976, before operations began. T h e N B B li n e is s e e n i n t h e c e ntr e; o n t h e ri g ht is t h e p uls e tr a nsf or m er f or t h e W B B h or n, b ut t h e h or n its elf, d esti n e d f or t h e p e d est al o n t h e l eft, is n ot y et i nst all e d. At t h e f ar e n d, t h e 2. 5 m dia meter titaniu m windo w of the evacuated decay region can be seen. 4 8 9 Fi g u r e 2 Neutrino and antineutrino energy spectra, calculated for the horn-focused W B B and the more conventional N B B. W B Bs are c haracterize d b y hi g h i nte nsit y, a stee p ( ge nerall y u n desira ble) energy fall-off, an d a s ubstantial conta mination of wrong-“sign” ne utrinos. T h e N B Bs h a v e l o w er i nt e nsit y, a fl at e n er g y d e p e n d e n c e i n t h e c o ntri b u- tion fro m each of the t wo decays, and s mall wrong-sign background. They also ha ve t he i m porta nt feat ure t hat t he e ner g y of t he ne utri no ca n be kno wn, s ubject to a t wofol d π - K dichoto my, if the decay angle is kno wn. In general this can be inferre d fro m the i m pact para meter of the event in the detect or. 3. DETE CT ORS The lo w cross-sections of ne utrinos are reflecte d in t wo general feat ures of ne utri n o detect ors: i) t hey are massi ve; ii) t he tar get ser ves also as detector. In the seventies, the most s uccessf ul detectors were large b ubble cha mbers. T h e m ost s pl e n di d of t h es e w er e t h e cr y o g e ni c d e vi c es b uilt at C E R N a n d Fer mila b, eac h wit h a vol u me of ~ 1 5 m 3 , i n l ar g e m a g n eti c fi el ds, a n d ca pa ble of o perati n g wit h li q ui d h y dro ge n, de uteri u m, or neo n. A pict ure of a ty pical ne utrino event in the C E R N cha mber is sho wn in Fig ure 3. It is a n exa m ple of t he “c harge d-c urre nt” ( C C) reactio n v + N → µ − + ha dro ns. Ho wever, one of the major discoveries at C E R N was ma de not in this but in a lar g e Fr e o n-fill e d b u b bl e c h a m b er, aff e cti o n at el y c all e d G ar g a m ell e. T h e a cti v e v ol u m e w as a c yli n d er 4. 8 m l o n g a n d 1. 9 m i n di a m et er, f or a v ol u m e of a b o ut 13 m 3 , i nsi d e a m a g n et pr o d u ci n g a fi el d of 2 T. Fi g ur e 4 gi v es so me i m pressio n of its size. The bubble cha mber has no w been largely replace d by detectors base d on electro nic detectio n met ho ds. As a n exa m ple, I me ntio n here t he C D HS P h ysics 1988 Figure 3 A typical neutrino event as ob- Fi g ure 4 Pre parati o n of t he i nteri or of t he served in the Big European Bubble Cha m- 1 3 m 3 bubble cha mber Garga melle, later to b er ( B E B C) fill e d wit h n e o n at t h e C E R N b e fill e d wit h Fr e o n.
Recommended publications
  • Research Article an Appraisal of Muon Neutrino Disappearance at Short Baseline
    Hindawi Publishing Corporation Advances in High Energy Physics Volume 2013, Article ID 948626, 11 pages http://dx.doi.org/10.1155/2013/948626 Research Article An Appraisal of Muon Neutrino Disappearance at Short Baseline L. Stanco,1 S. Dusini,1 A. Longhin,2 A. Bertolin,1 and M. Laveder3 1 INFN-Padova, Via Marzolo 8, 35131 Padova, Italy 2 Laboratori Nazionali di Frascati, INFN, Via E. Fermi 40, 00044 Frascati, Italy 3 Padova University and INFN-Padova, Via Marzolo 8, 35131 Padova, Italy Correspondence should be addressed to L. Stanco; [email protected] Received 20 June 2013; Revised 12 September 2013; Accepted 6 October 2013 Academic Editor: Kate Scholberg Copyright © 2013 L. Stanco et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Neutrino physics is nowadays receiving more and more attention as a possible source of information for the long-standing problem of new physics beyond the Standard Model. The recent measurement of the third mixing angle 13 in the standard mixing oscillation scenario encourages us to pursue the still missing results on leptonic CP violation and absolute neutrino masses. However, several puzzling measurements exist which deserve an exhaustive evaluation. Wewill illustrate the present status of the muon disappearance measurements at small / and the current CERN project to revitalize the neutrino field in Europe with emphasis on the search for sterile neutrinos. We will then illustrate the achievements that a double muon spectrometer can make with regard to discovery of new neutrino states, using a newly developed analysis.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Puzzling out Neutrino Mixing Through Golden Measurements
    Universidad Aut´onoma de Madrid Facultad de Ciencias Departamento de F´ısica Te´orica Puzzling out neutrino mixing through golden measurements Memoria de Tesis Doctoral realizada por Olga Mena Requejo, presentada ante el Departamento de F´ısica Te´orica de la Universidad Aut´onoma de Madrid para la obtenci´on del T´ıtulo de Doctora en Ciencias. Tesis Doctoral dirigida por la Catedr´atica M. Bel´en Gavela Legazpi, del Departamento de F´ısica Te´orica de la Universidad Aut´onoma de Madrid Madrid, Noviembre 2002. Agradecimientos “Erase´ una vez....” siempre me ha fascinado el principio de los cuentos infantiles (era el ´unico susurro que lograba escuchar segundos antes de conciliar el sue˜no), pero hoy intentar´emantenerme despierta..., una taza de caf´e, un bostezo,..., y seguro que yo tambi´en puedo contar un buen cuento, como mis abuelas...voy a intentarlo... “....una estudiante de F´ısicas, una entre los (400) j´ovenes estudiantes que se ma- triculan cada a˜no en la Universidad Aut´onoma∼O de Madrid, UAM para los amigos. Durante su tercer y cuarto a˜no de estudios, curs´ociertas asignaturas que realmente le impactaron, como la Mec´anica Cu´antica y la Mec´anica Te´orica. Un a˜no antes de li- cenciarse, acudi´oal despacho de la que hab´ıasido su profesora de Mec´anica Cu´antica, Bel´en Gavela, y le pregunt´oacerca de seguir investigando en F´ısica Te´orica con su ayuda. Bel´en la apoy´oy anim´o, la escuch´oy discuti´ocon ella cada tema que estudi- aba, le cedi´olibros, art´ıculos y trat´ode desnudar la F´ısica ante sus ojos.
    [Show full text]
  • Download This Article in PDF Format
    The Second Lepton Family Klaus Winter, CERN The Nobel Prize for Physics for 1988 was awarded to L. Lederman, M. Schwartz and J. Steinberger for work on neutrinos in the early 1960s. In a letter [1] addressed to the "dear radioactive ladies and gentlemen", writ­ ten in December 1930, Wolfgang Pauli proposed, as a "desperate remedy" to save the principle of conservation of energy in beta-decay, the idea of the neutrino, a neutral particle of spin 1/2 and with a mass not larger than 0.01 proton mass. "The continuous beta-spectrum [2] would then become understandable by the assumption that in beta-decay a neutrino is emitted together with the electron, in such a way that the sum of the energies of the neutrino and electron is constant." Pauli did not specify at that time Fig. 1 — A recent photograph taken at CERN of Leon Lederman (left), whether the neutrino was to be ejected Jack Steinberger (centre) and Melvin Schwartz. or created. In his famous paper "An attempt of a theory of beta-decay" [3] the muon not decay into e + at the rate ween 1 and 2 GeV should be achievable. E. Fermi used the neutrino concept of predicted if such a non-locality exis­ Would these synchrotrons though, deli­ Pauli together with the concept of the ted ? ". On this view the muon would vir­ ver enough neutrinos? According to nucleon of Heisenberg. He assumed tually dissociate into W + v, the charged their specifications they should accele­ that in beta-decay a pair comprising an W would radiate a and W + v would rate 1011 protons per second, an unpre­ electron and a neutrino is created, analo­ recombine to an electron.
    [Show full text]
  • 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.
    [Show full text]
  • Particle Detectors Lecture Notes
    Lecture Notes Heidelberg, Summer Term 2011 The Physics of Particle Detectors Hans-Christian Schultz-Coulon Kirchhoff-Institut für Physik Introduction Historical Developments Historical Development γ-rays First 1896 Detection of α-, β- and γ-rays 1896 β-rays Image of Becquerel's photographic plate which has been An x-ray picture taken by Wilhelm Röntgen of Albert von fogged by exposure to radiation from a uranium salt. Kölliker's hand at a public lecture on 23 January 1896. Historical Development Rutherford's scattering experiment Microscope + Scintillating ZnS screen Schematic view of Rutherford experiment 1911 Rutherford's original experimental setup Historical Development Detection of cosmic rays [Hess 1912; Nobel prize 1936] ! "# Electrometer Cylinder from Wulf [2 cm diameter] Mirror Strings Microscope Natrium ! !""#$%&'()*+,-)./0)1&$23456/)78096$/'9::9098)1912 $%&!'()*+,-.%!/0&1.)%21331&10!,0%))0!%42%!56784210462!1(,!9624,10462,:177%&!(2;! '()*+,-.%2!<=%4*1;%2%)%:0&67%0%&!;1&>!Victor F. Hess before his 1912 balloon flight in Austria during which he discovered cosmic rays. ?40! @4)*%! ;%&! /0%)),-.&1(8%! A! )1,,%2! ,4-.!;4%!BC;%2!;%,!D)%:0&67%0%&,!(7!;4%! EC2F,1-.,%!;%,!/0&1.)%21331&10,!;&%.%2G!(7!%42%!*H&!;4%!A8)%,(2F!FH2,04F%!I6,40462! %42,0%))%2! J(! :K22%2>! L10&4(7! =4&;! M%&=%2;%0G! (7! ;4%! E(*0! 47! 922%&%2! ;%,! 9624,10462,M6)(7%2!M62!B%(-.04F:%40!*&%4!J(!.1)0%2>! $%&!422%&%G!:)%42%&%!<N)42;%&!;4%20!;%&!O8%&3&H*(2F!;%&!9,6)10462!;%,!P%&C0%,>!'4&;!%&! H8%&! ;4%! BC;%2! F%,%2:0G! ,6! M%&&42F%&0! ,4-.!;1,!1:04M%!9624,10462,M6)(7%2!1(*!;%2!
    [Show full text]
  • 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�
    [Show full text]
  • 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.
    [Show full text]
  • Scientific and Related Works of Chen Ning Yang
    Scientific and Related Works of Chen Ning Yang [42a] C. N. Yang. Group Theory and the Vibration of Polyatomic Molecules. B.Sc. thesis, National Southwest Associated University (1942). [44a] C. N. Yang. On the Uniqueness of Young's Differentials. Bull. Amer. Math. Soc. 50, 373 (1944). [44b] C. N. Yang. Variation of Interaction Energy with Change of Lattice Constants and Change of Degree of Order. Chinese J. of Phys. 5, 138 (1944). [44c] C. N. Yang. Investigations in the Statistical Theory of Superlattices. M.Sc. thesis, National Tsing Hua University (1944). [45a] C. N. Yang. A Generalization of the Quasi-Chemical Method in the Statistical Theory of Superlattices. J. Chem. Phys. 13, 66 (1945). [45b] C. N. Yang. The Critical Temperature and Discontinuity of Specific Heat of a Superlattice. Chinese J. Phys. 6, 59 (1945). [46a] James Alexander, Geoffrey Chew, Walter Salove, Chen Yang. Translation of the 1933 Pauli article in Handbuch der Physik, volume 14, Part II; Chapter 2, Section B. [47a] C. N. Yang. On Quantized Space-Time. Phys. Rev. 72, 874 (1947). [47b] C. N. Yang and Y. Y. Li. General Theory of the Quasi-Chemical Method in the Statistical Theory of Superlattices. Chinese J. Phys. 7, 59 (1947). [48a] C. N. Yang. On the Angular Distribution in Nuclear Reactions and Coincidence Measurements. Phys. Rev. 74, 764 (1948). 2 [48b] S. K. Allison, H. V. Argo, W. R. Arnold, L. del Rosario, H. A. Wilcox and C. N. Yang. Measurement of Short Range Nuclear Recoils from Disintegrations of the Light Elements. Phys. Rev. 74, 1233 (1948). [48c] C.
    [Show full text]
  • New Physics with Neutrinos
    New Physics with Neutrinos Dissertation zur Erlangung des Grades \Doktor der Naturwissenschaften" am Fachbereich Physik, Mathematik und Informatik der Johannes Gutenberg-Universitat¨ in Mainz Mona Inge Dentler geboren in Munchen¨ Mainz, den 23.11.2018 Abstract Due to open problems in theory and unresolved anomalies in various oscilla- tion experiments, neutrino physics appears to be an excellent starting point in the quest for physics beyond the Standard Model (SM). The 3 + 1 framework featuring an additional, sterile neutrino mixing with the known neutrinos, is a minimalist extension of the SM which can account for oscillation phenomenology beyond the standard three flavor paradigm. However, two orthogonal arguments militate against this model. First, the increasing amount of ambiguous experimental results makes a con- sistent interpretation of the data in the 3 + 1 framework appear unlikely. In this regard, global fits provide a useful tool to investigate this objection. This thesis reports on the results of an up-to-date global fit to all relevant, available datasets, including the data corresponding to the reactor antineutrino anomaly (RAA), the gallium anomaly and the short baseline (SBL) anomaly. The reactor data as a special case can plausibly be explained by the hypothesis of a misprediction of the reactor antineutrino flux. Therefore, this hypothesis is tested against the 3 + 1 framework. Both hypotheses are found to be similarly likely, with a slight preference for the 3 + 1 framework, mainly driven by the data from DANSS and NEOS, which measure antineutrino spectra. However, a combination of both hypotheses fits the data best, with the hypothesis of a mere misprediction of the reactor flux rejected at 2:9σ.
    [Show full text]
  • 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.
    [Show full text]