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Poster: G-2 Measuring the Muon [Pdf]
g-2 measuring the muon In the 1950s the muon was still a complete enigma. Physicists could In 1959, six physicists joined forces to try to measure the muon’s The second g-2 experiment started in 1966 under the leadership magnetic moment using CERN’s first accelerator, the Synchrocyclotron. of Francis Farley and it achieved a precision 25 times higher than not yet say with certainty whether it In 1961, the team published the first direct measurement of the muon’s the previous one. This allowed phenomena predicted by the theory anomalous magnetic moment to a precision of 2% with respect to of quantum electrodynamics to be observed with a much greater the theoretical value. By 1962, this precision had been whittled down sensitivity — vacuum polarisation for instance, which is the momentary was simply a much heavier electron to just 0.4%. This was a great success since it validated the theory of appearance of ‘virtual’ electron and antielectron pairs with very short quantum electrodynamics. As predicted, the muon turned out to be lifetimes. The experiment also revealed a quantitative discrepancy a heavy electron. with the theory and thus prompted theorists to re-calculate their or whether it belonged to another predictions. species of particle. g-2 was set up to “g-2 is not an experiment: it is a way of life.” John Adams test quantum electrodynamics, which predicts, among other things, an A third experiment, with a new technical approach, was launched in anomalously high value for the muon’s 1969, under the leadership of Emilio Picasso. -
Vertex Detectors - a Historical Overview
Vertex Detectors - a historical overview Chris Damerell (RAL, Open U and Oxford U) CONTENTS • History from perspective of our RAL group – unavoidably biased … • Also, developments under study by our new collaboration (all pixel-based): • detectors for particle tracking systems with enhanced performance (notably much reduced material) • X-ray detectors for 4th generation light sources (FELs including UKFEL if it happens) • detectors for super-resolution optical microscopy 24th August 2016 RAL PPD seminar Chris Damerell 1 1969 Expt S120. Hypercharge exchange processes at CERN PS. Tony G, Fred W, Blair Ratcliff Clean test of the bootstrap theory of hadronic interactions Ideas for a focusing spectrometer for SPS startup, to definitively test this theory Need for few mm precision tracking … 1970 Supported by Godfrey Stafford (amazingly, given his challenges when appointed Director of RHEL in 1969) - invited talk to the Lab’s Scientific Policy Committee Visit to Alvarez group; initiated then shelved ideas for liquid xenon MWPC .. 1972 Bootstrap theory was disintegrating without our help. We joined CERN-Munich group to create the ACCMOR Collaboration, Experiment WA3; relatively conventional physics (meson spectroscopy with multi-particle spectrometer) but wonderful colleagues 24th August 2016 RAL PPD seminar Chris Damerell 2 Charm Pre-History and Discovery 1964 Bjorken and Glashow predicted the charm quark on general grounds. Key properties of D mesons included: decay nearly always to kaons, and with relatively high multiplicity. Physics case strengthened later by GIM mechanism to suppress strangeness-changing neutral currents. But as with the Higgs boson, experimental interest was at first non-existent – there was so much more ‘solid physics’ to do, such as discovering the patterns of meson and baryon resonances. -
Der Mythos Der Deutschen Atombombe
Langsame oder schnelle Neutronen? Der Mythos der deutschen Atombombe Prof. Dr. Manfred Popp Karlsruher Institut für Technologie Ringvorlesung zum Gedächtnis an Lise Meitner Freie Universität Berlin 29. Oktober 2018 In diesem Beitrag geht es zwar um Arbeiten zur Kernphysik in Deutschland während des 2.Weltkrieges, an denen Lise Meitner wegen ihrer Emigration 1938 nicht teilnahm. Es geht aber um das Thema Kernspaltung, zu dessen Verständnis sie wesentliches beigetragen hat, um die Arbeit vieler, gut vertrauter, ehemaliger Kollegen und letztlich um das Schicksal der deutschen Physik unter den Nationalsozialisten, die ihre geistige Heimat gewesen war. Da sie nach dem Abwurf der Bombe auf Hiroshima auch als „Mutter der Atombombe“ diffamiert wurde, ist es ihr gewiss nicht gleichgültig gewesen, wie ihr langjähriger Partner und Freund Otto Hahn und seine Kollegen während des Krieges mit dem Problem der möglichen Atombombe umgegangen sind. 1. Stand der Geschichtsschreibung Die Geschichtsschreibung über das deutsche Uranprojekt 1939-1945 ist eine Domäne amerikanischer und britischer Historiker. Für die deutschen Geschichtsforscher hatte eines der wenigen im Ergebnis harmlosen Kapitel der Geschichte des 3. Reiches keine Priorität. Unter den alliierten Historikern hat sich Mark Walker seit seiner Dissertation1 durchgesetzt. Sein Beitrag zur Geschichte der Kaiser Wilhelm-Gesellschaft im 3. Reich beginnt mit den Worten: „The Kaiser Wilhelm Institute for Physics is best known as the place where Werner Heisenberg worked on nuclear weapons for Hitler.“2 Im Jahr 2016 habe ich zum ersten Mal belegt, dass diese Schlussfolgerung auf Fehlinterpretationen der Dokumente und auf dem Ignorieren physikalischer Fakten beruht.3 Seit Walker gilt: Nicht an fehlenden Kenntnissen sei die deutsche Atombombe gescheitert, sondern nur an den ökonomischen Engpässen der deutschen Kriegswirtschaft: „An eine Bombenentwicklung wäre [...] auch bei voller Unterstützung des Regimes nicht zu denken gewesen. -
H E Rm Ordes O Ff[F2y Years Cf Research
1954-2004 CERN H e rmordes o ff[F2y years cf research SCIENCES HISTOIRE EDITIONS SUZANNE HURTER Contents Foundations for European science 1954 CERN is created by 12 European countries to revive science on the continent 2 Franwis de Rose: A noble cause 7 1955 On neutral territory Geneva is chosen as the site for the future Laboratory 10 Maurice Bourquin: The Geneva spirit in the field of science 14 1957 A place for theorists The theory group, initially hosted in Copenhagen, is the first group to be created 16 Jacques Prentki: All good friends 18 Tatiana Faberg:Theory in practice 20 1957 A machine for learning The first accelerator, the Synchrocyclotron (SC), begins Operation 22 Franco Bonaudi: Great enthusiasm 26 1958 Already a discovery! Experiments begin at the Synchrocylotron (SC) and important results soon appear 28 Giuseppe Fidecaro: The news went around the world 30 1959 The heut of CERN The Proton Synchrotron (PS), an innovative and powerful accelerator, starts up 32 Günther Plass: A dream come true 36 1959 The dark side of the muon A series of experiments on the muon begins and will last more than 20 years 38 Francis Farley: What invention is all about 40 1961 A new direction CERN gains new drive by adopting new long-term planning 42 Mervyn Hine: Still more applied physics! 44 1963 The collider way An experimental accelerator, CESAR, tests new, essential techniques for colliders 46 Heribert Koziol: On the hunt with CESAR 48 1963 Sharing knowledge The training service is created to contribute to CERNs obligation to educate -
Summer 1994 Vol
p A PERIODICAL OF PARTICLE PHYSICS SUMMER 1994 VOL. 24, NUMBER 2 Editors RENE DONALDSON, MICHAEL RIORDAN Executive Editor BILL KIRK Editorial Advisory Board JAMES BJORKEN, ROBERT N. CAHN, DAVID HITLIN, JOEL PRIMACK, NATALIE ROE, HERMAN WINICK Illustrations page z TERRY ANDERSON Production VANI BUSTAMANTE RAY ISLE Photographic Services TOM NAKASHIMA Distribution CRYSTAL TILGHMAN page 21 The Beam Line is published quarterly by the Stanford Linear Accelerator Center, PO Box 4349, Stanford, CA 94309. Telephone: (415) 926-2585 INTERNET: [email protected] BITNET: BEAMLINE@SLACVM FAX: (415) 926-4500 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 policy of the Stanford Linear Accelerator Center. Cover: A transverse profile of an electron beam in the SLAC linac. Particle densities have been color coded. The bright, high-density core contains 3 x 1010 electrons. These elec- tron (and positron) beams are focused to diameters of less than a micron at their collision point, which is located at the center of the SLD detector. Printed on recycled paper As CONTENTS FEATURES 2 THE HEART OF A NEW MACHINE After years of effort, the world's first linear collider is producing exciting physics results at Stanford. Nan Phinney 12 WHATEVER HAPPENED TO THE THEORY OF EVERYTHING? A brief report on the current status of string theory. Lance Dixon 21 OPINIONS ABOUT EVERYTHING: EPAC '94 In which Werner tells about his summer vacation in London. Werner Joho -, -. I DEPARTMENTS 28 THE UNIVERSE AT LARGE Fossil Radioactivities & How We Knm .""''i 3 5 the Solar System Formed in a Hurry 10 m | Virginia Trimble 38 CONTRIBUTORS page 12 40 FROM THE EDITORS' DESK DATES TO REMEMBER page 28 The e0 New |yI .:, byNA...D :2:- i iE I I..- PHINNEY After-::IE:I:: years of effort, st linear collider is producinf results at Stanford. -
ISOLDE and Nuclear Structure PG Hansen
CHS-35 February 1992 CERN LIBRARIES, GENEY A Illlllll l!llll ll llllllll lll lllll lllll lllll lllll lllll lllll lllll llll llll CM-P00043022 The SC: ISOLDE and Nuclear Structure P.G. Hansen GENEVA 1992 The Study of CERN History is a project financed by institutions m several CERN Member States. This report presents preliminary findings, and is intended for incorporation into a more comprehensive study of CERN's history. It is distributed primarily to historians and scientists to provoke discussion, and NO PART OF IT SHOULD BE CITED OR REPRODUCED WITHOUT THE WRITTEN PERMISSION OF THE AUTHOR. Comments and criticism are welcome, and should be sent to the author at Institute of Physics and Astronomy University of Aarhus DK-8000 Aarhus Denmark. Copyright History of CERN Project, Geneva, 1992 The SC: ISOLDE and Nuclear Structure P.G. Hansen GENEVA 1992 The SC: ISOLDE and Nuclear Structure P.G. Hansen Institute of Physics and Astronomy, Aarhus University DK-8000 Aarhus 1. Introduction 2. The early interest in nuclear physics at CERN 2.1 The conferences on High-Energy Physics and Nuclear Structure and Nuclei Far From Stability 2.2 CERN's Nuclear Structure Committee (1964-66) and other scientific committees 2.3 Studies of complex nuclear reactions by radiochemical methods 2.4 Open problems in nuclear physics in the sixties and seventies 3. Experiments with muons and pions 3.1 Muonic x-rays 3.2 Pions and nuclei 3.3 Tests of quantum electrodynamics and the masses of the pion and the muon 3.4 Scattering and production of pions on nuclei 3.5 Other experiments with muons 3.6 Looking back 4. -
Hitler's Uranium Club, the Secret Recordings at Farm Hall
HITLER’S URANIUM CLUB DER FARMHALLER NOBELPREIS-SONG (Melodie: Studio of seiner Reis) Detained since more than half a year Ein jeder weiss, das Unglueck kam Sind Hahn und wir in Farm Hall hier. Infolge splitting von Uran, Und fragt man wer is Schuld daran Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. So ist die Antwort: Otto Hahn. The real reason nebenbei Die energy macht alles waermer. Ist weil we worked on nuclei. Only die Schweden werden aermer. Und fragt man, wer ist Schuld daran, Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. So ist die Antwort: Otto Hahn. Die nuclei waren fuer den Krieg Auf akademisches Geheiss Und fuer den allgemeinen Sieg. Kriegt Deutschland einen Nobel-Preis. Und fragt man, wer ist Schuld daran, Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. So ist die Antwort: Otto Hahn. Wie ist das moeglich, fragt man sich, In Oxford Street, da lebt ein Wesen, The story seems wunderlich. Die wird das heut’ mit Thraenen lesen. Und fragt man, wer ist Schuld daran Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. So ist die Antwort: Otto Hahn. Die Feldherrn, Staatschefs, Zeitungsknaben, Es fehlte damals nur ein atom, Ihn everyday im Munde haben. Haett er gesagt: I marry you madam. Und fragt man, wer ist Schuld daran, Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. So ist die Antwort: Otto Hahn. Even the sweethearts in the world(s) Dies ist nur unsre-erste Feier, Sie nennen sich jetzt: “Atom-girls.” Ich glaub die Sache wird noch teuer, Und fragt man, wer ist Schuld daran, Und fragt man, wer ist Schuld daran, So ist die Antwort: Otto Hahn. -
Theoretical Status of the Muon G 2 −
Theoretical status of the muon g 2 − Andreas Nyffeler Institute of Nuclear Physics Johannes Gutenberg University, Mainz, Germany [email protected] Service de Physique Th´eorique Universit´eLibre de Bruxelles, Belgium January 29, 2016 Outline • Basics of the anomalous magnetic moment • Electron g 2: Theory, Experiment at Harvard, Determination of α − • Muon g 2: − • Brookhaven Experiment • Theory: QED, weak interactions, hadronic contributions (HVP, HLbL) • Current status of the muon g − 2 • New Physics contributions to the muon g 2 − • Complementarity between precision physics at low energies and searches for New Physics at high-energy colliders • New Physics contributions to g − 2: general observations • Supersymmetry • Dark Photon • Conclusions and Outlook Basics of the anomalous magnetic moment Electrostatic properties of charged particles: Charge Q, Magnetic moment ~µ, Electric dipole moment ~d For a spin 1/2 particle: e 1 ~µ = g ~s; g = 2(1 + a); a = (g 2) : anomalous magnetic moment 2m | {z } 2 − Dirac Long interplay between experiment and theory: structure of fundamental forces In Quantum Field Theory (with C,P invariance): γ(k) 2 3 iσµν k µ 2 ν 2 =( ie)¯u(p 0) 6 F (k ) + F (k )7 u(p) γ 1 2 4 5 − 2m | {z } | {z } p p’ Dirac Pauli F1(0) = 1 and F2(0) = a 2 ae : Test of QED. Most precise determination of α = e =4π. aµ: Less precisely measured than ae , but all sectors of Standard Model (SM), i.e. QED, Weak and QCD (hadronic), contribute significantly. Sensitive to possible contributions from New Physics. Often (but not always !): 2 2 m` mµ a` 43000 more sensitive than ae [exp. -
Jan/Feb 2015
I NTERNATIONAL J OURNAL OF H IGH -E NERGY P HYSICS CERNCOURIER WELCOME V OLUME 5 5 N UMBER 1 J ANUARY /F EBRUARY 2 0 1 5 CERN Courier – digital edition Welcome to the digital edition of the January/February 2015 issue of CERN Courier. CMS and the The coming year at CERN will see the restart of the LHC for Run 2. As the meticulous preparations for running the machine at a new high energy near their end on all fronts, the LHC experiment collaborations continue LHC Run 1 legacy to glean as much new knowledge as possible from the Run 1 data. Other labs are also working towards a bright future, for example at TRIUMF in Canada, where a new flagship facility for research with rare isotopes is taking shape. To sign up to the new-issue alert, please visit: http://cerncourier.com/cws/sign-up. To subscribe to the magazine, the e-mail new-issue alert, please visit: http://cerncourier.com/cws/how-to-subscribe. TRIUMF TRIBUTE CERN & Canada’s new Emilio Picasso and research facility his enthusiasm SOCIETY EDITOR: CHRISTINE SUTTON, CERN for rare isotopes for physics The thinking behind DIGITAL EDITION CREATED BY JESSE KARJALAINEN/IOP PUBLISHING, UK p26 p19 a new foundation p50 CERNCOURIER www. V OLUME 5 5 N UMBER 1 J AARYN U /F EBRUARY 2 0 1 5 CERN Courier January/February 2015 Contents 4 COMPLETE SOLUTIONS Covering current developments in high-energy Which do you want to engage? physics and related fi elds worldwide CERN Courier is distributed to member-state governments, institutes and laboratories affi liated with CERN, and to their personnel. -
Wolfgang GENTNER Research Director
Who is who in CERN Research Director Wolfgang GENTNER Synchro-cyclotron Division The group of visiting scientists headed Wolfgang Gentner then returned to by Prof. A. Lagarrigue, from the Eco'k Germany where he became Prof. W. Polyfechnique in Paris, arrived at the Bothe's assistant at the Kaiser Wilhelm 25 GeV synchrotron on 1 July. Institute (now the Max-Planck Institute) The group is placing a large piece of in Heidelberg. There, he continued his experimental equipment weighing near work on gamma rays. In particular, he ly 100 ions in the synchrotron beam. determined their photonuclear effects on This is a propane-freon bubble chamber all the elements. For this work, he used measuring 1 x 0.5 x 0.5 m, installed in gamma rays at 17 MeV—the highest en time to take its first photographs on ergy gamma rays which had so far been 22 July and take part in a long experi obtained—produced by the reaction of ment on 8 and 9 August. After Prof. lithium when bombarded by protons B. Hahn's Group from the Swiss Univer at an energy of a million electronvolt. sity of Fribourg, which will take part In October, Prof. Centner will resign The protons were provided by a 1 MeV in experiments during the whole of I960, from his duties as Research Director of Van de Graaff electrostatic accelerator this is the second team of physicists the Synchro-cyclotron Division to be constructed by the young physicist. from the Member States to come and come Director of the Max-Planck Re At the beginning of 1939, Wolfgang work at CERN. -
Theoretical Status of the Muon G 2 −
Theoretical status of the muon g 2 − Andreas Nyffeler PRISMA Cluster of Excellence, Institut f¨urKernphysik, Helmholtz-Institut Mainz Johannes Gutenberg Universit¨atMainz, Germany [email protected] KEK, Tsukuba, Japan, December 1, 2016 Outline Basics of the anomalous magnetic moment • Electron g 2, determination of α • − Muon g 2: QED, weak interactions, hadronic contributions • − Hadronic vacuum polarization (HVP) • Hadronic light-by-light scattering (HLbL) • A data-driven approach to HLbL using dispersion relations • Precision of a data-driven approach to HLbL: pseudoscalar-pole • contribution New Physics contributions to the muon g 2 • − Conclusions and Outlook • Basics of the anomalous magnetic moment Electrostatic properties of charged particles: Charge Q, Magnetic moment ~µ, Electric dipole moment ~d For a spin 1/2 particle: e 1 ~µ = g ~s; g = 2(1 + a); a = (g 2) : anomalous magnetic moment 2m | {z } 2 − Dirac Long interplay between experiment and theory: structure of fundamental forces In Quantum Field Theory (with C,P invariance): γ(k) 2 3 iσµν k 0 µ 2 ν 2 =( ie)¯u(p ) 6γ F (k ) + F (k )7 u(p) 1 2 4 5 − 2m | {z } | {z } p p’ Dirac Pauli F1(0) = 1 and F2(0) = a 2 ae : Test of QED. Most precise determination of α = e =4π. aµ: Less precisely measured than ae , but all sectors of Standard Model (SM), i.e. QED, Weak and QCD (hadronic), contribute significantly. Sensitive to possible contributions from New Physics. Often (but not always !): 2 2 m` mµ a` 43000 more sensitive than ae [exp. precision factor 19] ∼ mNP ) me ∼ ! Anomalous magnetic moment in quantum field theory Quantized spin 1=2 particle interacting with external, classical electromagnetic field 4 form factors in vertex function (momentum transfer k = p0 p, not assuming parity or charge conjugation invariance) − i p0; s0 jµ(0) p; s ≡ h j j i " µν 0 0 µ 2 iσ kν 2 = ( ie)¯u(p ; s ) γ F1(k ) + F2(k ) − | {z } 2m | {z } γ(k) Dirac Pauli # σµν k 5 ν 2 5 2 µ µ 2 + F (k ) + k k k F (k ) u(p s) γ 3 γ γ = 4 ; 2m − p p’ µ 2 k= = γ kµ. -
The Virus House -
David Irving The Virus House - F FOCAL POINT Copyright © by David Irving Electronic version copyright © by Parforce UK Ltd. All rights reserved No reproduction, copy or transmission of this publication may be made without written permission. Copies may be downloaded from our website for research purposes only. No part of this publication may be commercially reproduced, copied, or transmitted save with written permission in accordance with the provisions of the Copyright Act (as amended). Any person who does any unauthorised act in relation to this publication may be liable to criminal prosecution and civil claims for damages. To Pilar is the son of a Royal Navy commander. Imper- fectly educated at London’s Imperial College of Science & Tech- nology and at University College, he subsequently spent a year in Germany working in a steel mill and perfecting his fluency in the language. In he published The Destruction of Dresden. This became a best-seller in many countries. Among his thirty books (including three in German), the best-known include Hitler’s War; The Trail of the Fox: The Life of Field Marshal Rommel; Accident, the Death of General Sikorski; The Rise and Fall of the Luftwaffe; Göring: a Biography; and Nuremberg, the Last Battle. The second volume of Churchill's War appeared in and he is now completing the third. His works are available as free downloads at www.fpp.co.uk/books. Contents Author’s Introduction ............................. Solstice.......................................................... A Letter to the War Office ........................ The Plutonium Alternative....................... An Error of Consequence ......................... Item Sixteen on a Long Agenda............... Freshman................................................... Vemork Attacked.....................................