DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States LA-11177-C Government. Neither (he United States Government nor any agency thereof, nor any of their Conference 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- UC-34 ence herein to any specific commercial product, process, or service by trade name, trademark, Issued: December 1987 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 author:, expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Proceedings of the LAMPF Workshop on Photon and Neutral Meson Physics at Intermediate Energies LA—11177-C DE88 004703 LOS ALAMOS NATIONAL LABORATORY LOS ALAMOS, NEW MEXICO JANUARY 7-9, 1987 EDITED BY H. W. Baer, H. Crannell,* and R. J. Peterson " Organizing Committee H. Crannell, Chairman R. A. Eisenstein E. C. Booth R. J. Peterson H. W. Baer Sponsored by Medium-Energy Physics Division •Physics Department, Catholic University of America, Washington. DC 20064. "Nuclear Physics Laboratory, University of Colorado, Campus Box 446. Boulder. CO 80309. Los Alamos National Laboratory Los Alamos, New Mexico 87545 OF THIS DOCUMFNT IS UNLIMITED PREFACE This volume contains the Proceedings of the Workshop on "Photon and Neutral- Meson.Physics at Intermediate Energies," held at Los Alamos, New Mexico, January 7-9, 1987. The purpose of this workshop was to bring together scientists working in the areas of electromagnetic, heavy-ion, and light hadron physics to discuss both the physics that could be addressed and potential capabilities of new, large intermediate-energy photon detectors. Based on the papers contained in these proceedings, it appears clear that there are a number of important areas that could be addressed with a much higher resolution neutral meson detector. It is also clear that the technical capability for building a neutral meson detector for energies up to 4 GeV with solid angle of approximately 10 mrs and resolution of a few hundred keV now exists. It also appears entirely reasonable to construct such a detector to be easily transportable so that it would become a national facility, available for use at a number of different laboratories. From the many interesting papers presented and from the broad representation of physicists from laboratories in Asia, Canada, Europe, Japan, and the United States, there appears to be a strong case for proceeding with the construction of such a detector. We are grateful to Gerry Garvey, Don Hagerman, and James Bradbury for their sup- port and advice. Special thanks go to Maxinc Joppa and Roberta Marinuzzi for attending to all the workshop arrangements. We wish to add a special thanks to Karen Poelakker for her assistance in the preparation of these proceedings. The cost of the Workshop not covered by registration fees was borne by the LAMPF Laboratory. Helmut Baer Hall Crannell R. J. Peterson Editors iv CONTENTS PROGRAM vii /. INTRODUCTION AND OVERVIEW 1 Introduction and Goals of the Workshop Hall Crannell (Catholic University of America) 1 Design of a High Resolution Spectrometer J. David Bowman (Los Alamos National Laboratory) 5 Basic Nuclear Structure Studies with Pions Naftali Auerbach (Tel Aviv University) 26 Photonuclear Physics Above Pion Threshold Justus Koch (NIKHEF) 59 //. PHOTONUCLEAR REACTIONS 81 JI° Production with Monochromatic Photons Near Threshold Hans Stroher (Giessen) 81 Photoproduction of n^s in the Delta Resonance Region Robert Redwine (Massachusetts Institute of Technology) 97 Photoproduction of T\ Mesons Frank Tabakin (University of Pittsburgh) 114 Coherent Nuclear Photon Scattering Near A Resonance Energies James Miller (Boston University) 165 ///. HADRON INTERACTIONS 183 A 7t° Spectrometer for Low-Energy Heavy-Ion Reactions G. R. Young (Oak Ridge National Laboratory) 183 Eta Meson Production Experiments J. C. Peng (Los Alamos National Laboratory) 201 Nuclear Structure Studies with (n, 7t°) Reactions R. J. Peterson (University of Colorado) 230 A Unified Theory of Pion Reactions and Nuclear Structure Mikkel B. Johnson (Los Alamos National Laboratory) 274 IV. PHOTON DETECTION 303 Status of BGO Calorimetry in L3 David P. Stickland (Princeton University) 303 Development of Liquid Argon Detectors Kimiaki Masuda (Saitama College of Health) 329 Meson Spectroscopy at LEAR with a 4rc Neutral and Charged Particle Detector Peter Truol (Zurich) 344 V. NEW RESULTS 362 Improving Scintillation Crystals Using Muon Tomography D. H. Dowell (Brookhaven National Laboratory) 362 Photon Vertex Reconstruction with a BGO Converter Daniel I. Sober (The Catholic University of America) 383 Performance of a BGO-Nal T| Spectrometer M. J. Leitch (Los Alamos National Laboratory) 393 Barium-Fluroide: A Universal Particle and Photon Detector H. Stroeher (Giessen) 408 Improving the Efficiency and Resolution of Large Nal Spectrometers Michael A. Kovash (University of Kentucky) 417 Study of the Reaction p + p—»p + p + rc° S. Stanislaus (University of British Columbia) 435 VI. FUNDAMENTAL PHYSICS \ 442 Pion Proton Bremsstrahlung and the Delta Magnetic Moment Curtis A. Meyer (University of California - Berkeley) 442 Radiative Processes in Kaon and Hyperon Physics B. L. Roberts (Boston University) 458 WORKSHOP SUMMARY 478 Workshop Summary Stanley S. Hanna (Stanford University) 478 ATTENDEES 483 vi PROGRAM LAMPF WORKSHOP on PHOTON AND NEUTRAL MESON PHYSICS January 7-9, 1987 Los Alamos Meson Physics Facility Wednesday. January 7. 1987 8:00 a.m. REGISTRATION I. INTRODUCTION AND OVERVIEW Chairman: Helmut Baer - Los Alamos National Laboratory 9:00 WELCOME - Gerald Garvty - Director, LAMPF 9:15 INTRODUCTION AND GOALS - Hall Crannell - Catholic University of America 9:30 David Bowman - Los Alamos National Laboratory "Design of a High Resolution Spectrometer" 10:15 COFFEE BREAK 10:45 Nafiali Auerbach - Tel Aviv University "Basic Nuclear Structure Studies with Pions" 11:40 Justus Koch - NIKHEF "Photonuclear Physics Above Pion Threshold" 12:35 p.m. LUNCH H. PHOTONUCLEAR REACTIONS Chairman: Evans Hayward 2:00 Hans Stroher- Giessen uit° Production with Monochromatic Photons Near Threshold" 2:40 Robert Redwine - Massachusetts Institute of Technology "Photoprodwction of ir° 's in the Delta Resonance Region" 3:20 COFFEE BREAK 3:50 Frank Tabakin - University of Pittsburgh "Eta Production with Photons" 4:35 James Miller- Boston University "Nuclear Photon Scattering at Delta Resonance Energies" 6:00 COCKTAIL PARTY - LOS ALAMOS ARTS CENTER Vll Thursday. January 8, 1987 III. HADRON INTERACTIONS Chairman: Robert Eisenatem 9:00 a.m. G. R. Young - Oak Ridge National Laboratory "A rr° Spectrometer for Low-Energy Heavy-Ion Reactions" 9:40 Jen-Ckieh Peng - Los Alamos National Laboratory "Eta Meson Production" 10:20 COFFEE BREAK 10:50 Roy J. Peterson - University of Colorado "High Resolution Pion Charge Exchange" 11:30 Mtkkel Jo nson - Los Alamos National Laboratory "Unified Theory of Nuclear Reactions and Structure" 12:15 p.m. LUNCH IV. PHOTON DETECTION Chairman: E. Barrie Hughes 2:00 David Stickland - Princeton University "BGO and the L3 Detector at LEP" 2:40 Kimiaki Masuda - Saitama College of Health "Development of Liquid Argon Detectors" 3:20 Peter Truol- Zurich "Meson Spectroscopy at LEAR with a 4* Neutral and Charged Particle Detector" 4:00 COFFEE BREAK V. NEW RESULTS Chairman: 4:30 David DoweU - Srookhaven National Laboratory "Improving Scintillation Crystals Using Muon Tomography" 4:50 Daniel Sober - Catholic University of America "Vertex Reconstruction" 5:05 Michael Leitch - Los Alamos National Laboratory "Performance of a BGO-Nal r\ Spectrometer" 5:20 Hans Stroher - Giessen "Barium-Fluoride: A Universal Photon and Particle Detector" 5:35 Michael Kovash - University of Kentucky "Improving the Efficiency and Resolution of Large Sodium Iodide Spectrometers" 5:50 Shirvel Stanislaus - University of British Columbia "Study of the Reaction p + p-+ p + p+ n°" Friday, January 9. 1987 VI. FUNDAMENTAL PHYSICS Chairman: Edward Booth 9:00 a.m. Alan Nathan - University of Illinois "Compton Scattering and the Poiamibility of tlie Proton" 9:40 W. Kenneth McFarlane - Temple University "Detectors for Pion Beta Decay" 10-20 COFFEE BREAK 10:50 Curtis Meyer - University of California - Berkeley "Picn Proton Bremsstrahlung and the Delta Magnetic Moment" 11:30 B. Lee Roberta - Boston University "Radiative Processes in Kaon and Hyperon Physics" 12:10 p.m. Stanley Hanna •• Stanford University "Workshop Summary" 1 00 FAREWELL LUNCHEON - BOCCACIO'S RESTAURANT Organizing Committee Hall L. Crannell, Chairman Catholic University of America Helmut W. Baer Los Alamos National Laboratory Edward C. Booth Boston University Robert A. Eisenatein University of Illinois J. Peteraon University of Colorado IX ABSTRACT Proceedings of the LAMPF Workshop on Photon and Neutral Meson Physics at Intermediate Energies, held at Los Alamos during the period January 7-9, 1987, are reported. The physics justification and detector technologies for building a new high-resolution, large-solid-angle neutral meson detector are presented. NEUTRAL MESON DETECTOR WORK 'HOP INTRODUCTION AND GOALS OF THE WORKSHOP BRIEF HISTORY This workshop on neutral