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Novel Results in Particle Physics (Vanderbilt, 1982) CONP-8205116 — DE84 00 4141 Novel Results in Particle Physics (Vanderbilt, 1982) NOTICE PORTIONS OF THIS REPORT ARE ILLEGIBLE. Jt has been reproduced from the bsst available copy to permit the broadest possible availability. *,,-,, ... 'OFTWSOOWWffiWT IS UNLIMITED DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of tbe United States Government or any agency thereof. AIP Conference Proceedings Series Editor: Hugh C. Wolfe Number 93 Particles and Fields Subseries No. 27 Novel Results in Particle Physics (Vanderbilt, 1982) Edited by R. S. Panvini, M. S. Alam, S. E. Csorna Vanderbilt University American Institute of Physics New York 1982 . ._ , y^ WSTTnWJTTONOFTHlS DOCUMENT IS UNLIMITED The Government reserves for itself and others acting on its behalf a royalty free, nonexclusive, irrevocable, world-wide license for governmental purposes to publish, distribute, translate, duplicate, exhibit, and perform any such data copyrighted by the contractor. Copying fees: The code at the bottom of the first page of each article in this volume gives the fee for each copy of the article made beyond the free copying permitted under the 1978 US Copyright Law. (See also the statement following "Copyright" below). This fee can be paid to the American Institute of Physics through the Copyright Clearance Center, Inc., Box 765, Schenectady, N.Y. 12301. Copyright © 1982 American Institute of Physics Individual readers of this volume and non-profit libraries, acting for them, are permitted to make fair use of the material in it, such as copying an article for use in teaching or research. Permission is granted to quote from this volume in scientific work with the customary acknowledgment of the source. To reprint a figure, table or other excerpt requires the consent of one of the original authors and notification to AIP. Republication or systematic or multiple reproduction of any material in this volume is permitted only under license from AIP. Address inquiries to Series Editor, AIP Conference Proceedings, AIP, 335 E. 45th St., New York, N. Y. 10017 L.C Catalog Card No. 82-73954 ISBN 0-88318-192-4 DOECONF- 82053 T FOREWORD This wasthe fifth international conference on particle physics at Vanderbilt, held May 22-24, 1982. The first conference in 1973 occurred shortly after the CERN ISR and Fermilab (then NAL) began yielding data and many of the talks at that time were from experiments with the new machines. In 1980 we had a topical conference on e+e- interactions; this year the title and theme of the conference was Novel Results in Particle Physics. Results presented this time included such diverse topics as quark searches (and discoveries?), evidence for a monopole, proton decay experiments, and the latest data from the new CERN proton-antiproton collider. Significant results from more conventional experiments were also presented. The theory talks stressed the physics of 100 GeV and beyond. This conference was organized with the expert advice from many people. E. Berger organized the theory talks and C. Baltay was our expert on neutrino experiments; both also helped in planning other aspects of the conference. D. Coyne and B. Wiik advised us on e+e~ experiments and a variety of people including D. Berley, J. Orear, and R. Slansky made suggestions and helped organize the quark search talks. K. Moffeit and N. Reay advised us about charmed particle lifetime experiments. Many aspects of the local organization of this conference were handled by my colleagues M. S. Alam and S. E. Csorna. Finally, and most importantly, credit goes again to my wife Doria who really made the conference possible by contributing her considerable organizational skills and personal commitment towards getting the job done. With all of the energy and enthusiasm provided by the people mentioned above, the bills could not have been paid without the assistance of grants from the National Science Foundation, the Department of Energy, and the Vanderbilt University Research Council. Robert S. Panvini Conference Chairman September 1982 TABLE OF CONTENTS Free Quark Searches The Search for Fractionally Charged Particles Klaus S. Lackner and George Zweig 1 Recent Results from the San Francisco State Quark Search Peter C. Abrams, Kimberly C. Coburn, David C. Joyce, Maureen L. Savage, Frederick Wm. Walters, Betty A. Young, Roger W. Bland, Robert T. Johnson, Christopher L. Hodges 15 Search for Free Quarks at PEP S. J. Freedman 24 Is Fractional Electric Charge Problematic for QCD? R. Slansky. 39 Observation of Fractional Charge of l/3e on Matter J. D. Phillips, W. M. Fairbank, C. R. Fisel 48 ^ree Quarks in the Early Universe Jay Orear 61 Theory Axions: Visible and Invisible Michael Dine 66 D-Lifetimes Bubble Chamber Experiments on Charmed Particle Lifetimes R. C. Field 77 Measurement of the Lifetimes of the Charmed D+, D° and F+ Mesons and A£ Charmed Baryon The Fermi lab Experiment 531 Collaboration 89 Measurements of Charmed Particle Lifetime with Electronic Techniques G. Bellini 105 Theory A Composite Model of the Weak Interactions L. F. Abbott 121 e e" Collisions Recent Results from CLEO Paul Avery 129 Recent Results from CUSB on Upsilon Spectroscopy P. M. Tuts 155 E E" Collisions: Results from PETRA E. Hilger 169 Some Recent Results for the MAC Detector at PEP MAC Collaboration: Colorado-Frascati-Northeastern- SLAC-Utah-Wisconsin 201 Recent Results from Mark II at PEP D. Schlatter 21- Neutrino and Beam Dump Experiments Prompt Neutrino Production by 400 GeV Proton Interactions Firenze-Michigan-Ohio State-Washington-Wisconsin Collaboration 225 Charm Production Measurements Using Prompt Muons Chicago, Caltech, FNAL, Rochester, Stanford Collaboration 241 Charged Current Neutrino Interactions Caltech, Columbia, Fermilab, Rochester, Rockefeller Collaboration 250 Recent Results on the v and \S Charged Current Cross Sections P. Igo-Kemenes . V . .v 269 Anti-Neutrino-Nucleon Charged Current Interaction Cross Sections Measured by the Fermilab 15' Ne-H? Bubble Chamber in a Dichromatic Beam Hawaii, LBL, FNAL Collaboration 283 Theory GUTs, SUSY GUTs and Super GUTs Mary K. Gail lard 291 Proton Decays The Experimental Aspects of Nucleon Decay Marvin L. Marshak 305 Nucleon Decay Experiments in Europe M. Rollier 314 Neutrino Oscillations, Neutrinoless Beta Decay Neutrino Oscillations, Neutrinoless Double Beta Decay F. Boehm 321 High Energy p~p Collisions First Results from the CERN-SPS Proton-Antiproton Collider M. Yvert 339 Further Results from the UA5 Collaboration H. L. Mulkens 364 Theory Problems, Puzzles, and Prospects: A Personal Perspective on Present Particle Physics H. David Politzer 375 Conference Program 385 List of Participants 387 The Search for Fractionally Charged Particles Klaus S. Lackner and George Zweig" Los Alamos National Laboratory Los Alamos, NM 8754-5 1. Do Fractionally Charged Particles Exist in Isolation? Quarks, the constituents of hadrons and the fermion fields of quantum chro- a modynamies, have fractional charges -V3e and /,e All charges arc integral multiples of Vse and not e, as was previously believed. Therefore it is natural to ask if isolated particles of fractional charge exist, cither as an intrinsic part of matter, or as particles that can be produced at high energy accelerators This question can only be answered by experiment, and remains interesting even if quantum chromodynamics turns out to be an absolutely confining theory of quarks. For example, small deviations from the standard version of quantum chromodynamics [i], or the incorporation of quantum chromodynamics into a more comprehensive theory [2-12], could require the existence of free frac- tionally charged particles *'. * Presently at the Stanford linear Accelerator " On leave from the California Institute of Technology '' "There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy." [Shakespeare: Hamlet I v.] 0094-243X/82/930001-14$3.00 Copyright 1982 American Institute of Physic 2. The Search for Fractionally Charged Particles. Quark production in high energy reactions is expected to be prohibitively small, Uven if uneonfined quarks exist, their production cross section has been estimated [ 13.14] to be I Ml w where Mq is the mass of the isolated quark and Uo is a symmetry breaking mass somewhere in the interval 0.3 to 3GeV/cz. The basic assumption underlying this estimate is that a quark-antiquark pair is connected by a string that has a cer- tain probability, per unit length per unit time, of breaking into two mesons. This string of gluonic flux fades out at distances larger than the symmetry breaking length l/y • Free quarks are produced if the quark-antiquark pair is separated further than this length, without breaking the string that binds them. In any case, sufficiently heavy fractionally charged particles cannot be pro- duced at accelerators since the threshold energy for their production cannot be reached. On the other hand, the "big bang" provides a potential source of fractionally charged particles, for example free quarks [14-24]. Presumably there was a time very early in the history of the universe when the mean separation between quarks was much less than their mean separation in hadrons. As the universe expanded and cooled, quarks eventually clustered in groups of three, forming protons and neutrons.
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