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The Investigation of Fundamental Interactions with Cold Neutrons

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The Investigation of Fundamental Interactions with Cold Neutrons A11102 14AL4A2A National Bureau o NBS Special Publication 711 The Investigation of Fundamental Interactions with Cold Neutrons G.L. Greene, Editor . TM he National Bureau of Standards' was established by an act of Congress on March 3, 1901. The Jf Bureau's overall goal is to strengthen and advance the nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau's technical work is performed by the National Measurement Laboratory, the National Engineering Laboratory, the Institute for Computer Sciences and Technology, and the Institute for Materials Science and Engineering The National Measurement Laboratory 2 Provides the national system of physical and chemical measurement; • Basic Standards coordinates the system with measurement systems of other nations and • Radiation Research furnishes essential services leading to accurate and uniform physical and • Chemical Physics chemical measurement throughout the Nation's scientific community, in- • Analytical Chemistry dustry, and commerce; provides advisory and research services to other Government agencies; conducts physical and chemical research; develops, produces, and distributes Standard Reference Materials; and provides calibration services. The Laboratory consists of the following centers: The National Engineering Laboratory Provides technology and technical services to the public and private sectors to Applied Mathematics address national needs and to solve national problems; conducts research in Electronics and Electrical 2 engineering and applied science in support of these efforts; builds and main- Engineering tains competence in the necessary disciplines required to carry out this Manufacturing Engineering research and technical service; develops engineering data and measurement Building Technology capabilities; provides engineering measurement traceability services; develops Fire Research 2 test methods and proposes engineering standards and code changes; develops Chemical Engineering and proposes new engineering practices; and develops and improves mechanisms to transfer results of its research to the ultimate user. The Laboratory consists of the following centers: The Institute for Computer Sciences and Technology Conducts research and provides scientific and technical services to aid Programming Science and Federal agencies in the selection, acquisition, application, and use of com- Technology puter technology to improve effectiveness and economy in Government Computer Systems operations in accordance with Public Law 89-306 (40 U.S.C. 759), relevant Engineering Executive Orders, and other directives; carries out this mission by managing the Federal Information Processing Standards Program, developing Federal ADP standards guidelines, and managing Federal participation in ADP voluntary standardization activities; provides scientific and technological ad- visory services and assistance to Federal agencies; and provides the technical foundation for computer-related policies of the Federal Government. The In- stitute consists of the following centers: The Institute for Materials Science and Engineering Conducts research and provides measurements, data, standards, reference Ceramics materials, quantitative understanding and other technical information funda- Fracture and Deformation 3 mental to the processing, structure, properties and performance of materials; Polymers addresses the scientific basis for new advanced materials technologies; plans Metallurgy research around cross-country scientific themes such as nondestructive Reactor Radiation evaluation and phase diagram development; oversees Bureau-wide technical programs in nuclear reactor radiation research and nondestructive evalua- tion; and broadly disseminates generic technical information resulting from its programs. The Institute consists of the following Divisions: 'Headquarters and Laboratories at Gaithersburg, Ml), unless otherwise noted; mailing address Gaithersburg, MD 20899. 2 Some divisions within the center are located at Boulder, CO 80303. 'Located at Boulder, CO, with some elements at Gaithersburg, MD. — NBS Special Publication 711 1 . fcui , i— — —~~ — ~—. The Investigation of Fundamental Interactions with Cold Neutrons Proceedings of a Workshop G.L. Greene, Editor Center for Basic Standards National Measurement Laboratory National Bureau of Standards Gaithersburg, MD 20899 Workshop Sponsors: Department of Energy National Bureau of Standards Issued February 1986 U.S. Department of Commerce Malcolm Baldrige, Secretary National Bureau of Standards Ernest Ambler, Director Library of Congress U.S. Government Printing Office For sale by the Superintendent Catalog Card Number: 86-600501 Washington: 1986 of Documents, National Bureau of Standards U.S. Government Printing Office, Special Publication 711 Washington, DC 20402 Natl. Bur. Stand. (U.S.), Spec. Publ. 711 164 pages (Feb. 1986) CODEN: XNBSAV Table of Contents The Particle Properties of the Neutron Norman F. Ramsey The NBS Cold Neutron Facility J.M. Rowe Cold and Ultra Cold Neutron Beams for P. Ageron and Fundamental Physics Research at the W. Mampe Institut Laue Langevin The Implications of Neutron Beta-Decay J. Byrne Review of the Measurements of the Neutron J.M. Robson Lifetime Absolute Neutron Flux Determination - D.M. Gilliam A Problem for the Measurement of t n and G.P. Lamaze The Determination of the Neutron Lifetime J.F. Wilkerson Using e-p Coincidence Determination of the Neutron Lifetime by J. Byrne, P. Counting Trapped Protons Dawber, R.D. Scott, J.M. Robson, and G.L. Greene In-Beam Neutron Lifetime Measurements at the D. Dubbers Institut Laue Langevin Neutron Lifetime Measurements with Bottled W. Mampe Neutrons at ILL Correlation Coefficients in Polarized Neutron S.J. Freedman Decay-Experiments with PERKEO Time Reversal Invariance in Polarized Neutron Thomas J. Beta Decay Bowles The Nucleon-Nucleon Weak Interaction E. G. Adelberger Tests of T-Invariance with Slow Neutrons P.K. Kabir Parity Violation in Capture of Polarized R. Wilson, M. Neutrons Avenier, G. Bagieu, R. Hart D.H. Koang, M.A. Idrissie, B. Vignon PNC and TNC Rotations of the Neutron Spin Blayne Heckel - Neutron Interf erometry : Present Status S.A. Werner and 95 Future Prospects H. Kaiser Perfect Crystal Systems for Advanced H. Rauch 106 Interferometer and Resonator Devices Long Wavelength Neutron Interf erometry Anton Zeilinger 112 Long Baseline Neutron Interf erometry R.D. Deslattes 118 An Effective Vibration Isolation System J. Arthur 124 for Perfect-Crystal Neutron Interf erometry Cold Neutrons and Neutron Oscillations Milla Baldo- 130 Ceolin Ultracold Neutrons and the Search for the J.M. Pendlebury 137 Electric Dipole Moment of the Neutron and K. Smith Superthermal Sources of Ultra-Cold Neutrons R. Golub 143 (UNO The Production of Slow Neutrons Using Doppler Thomas Dombeck 149 Shifting from a High-Speed Rotor and Their Applications in Fundamental Research. iv Preface The National Bureau of Standards currently operates a 20 MW research reactor on its campus in Gaithersburg, Maryland. By early 1986 a cryogenic moderator will be installed in the reactor core providing cold neutron fluxes which will be comparable to the most intense sources in the world. In order to fully benefit from this source, the National Bureau of Standards plans to establish, at this reactor, a National Cold Neutron Facility. This facility will consist of a large neutron guide hall as well as a wide variety of specialized instrumentation. The major thrust of the scientific effort at this facility will be in the area of materials research and condensed matter studies. However, as has been amply demonstrated at the only existing large cold neutron facility, the Institut Max von Laue-Paul Langevin in Grenoble, France, the research at such a facility is by no means limited to such areas. In the last decade a rather rich interdisciplinary effort has developed in which cold neutron beams have been used as tools in the investigation of fundamental interactions. This work draws on the techniques of particle physics, nuclear physics, atomic physics and optics. The results of such work have implications in the theory of the weak interaction, nuclear theory, and astrophysics as well as shedding light on the nature (and violation) of a variety of invariance laws and symmetry principles. In order to provide guidance in the development of such a research effort at the new National Cold Neutron Facility, the Department of Energy and the National Bureau of Standards sponsored, on 14-15 November 1985, a workshop on "The Investigation of Fundamental Interactions with Cold Neutrons". This workshop brought together more than 50 participants from 23 institutions in the U.S., Canada and Europe. The twenty-five papers that were presented comprise these proceedings. These contributions not only provide a review of recent work in this field but also describe a variety of future experiments in varying states of preparation. Taken together these papers describe a vital, exciting scientific endeavor which can be expected to provide significant results for many years to come. The organization of this workshop would not have been possible without the efforts of many individuals. In particular, Dr. Richard
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