Distribution Category - UNT Digital Library /67531/metadc... NUCLEAR PHYSICS RESEARCH Introduction 1

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  • Distribution Category: Physics -General

    (UC - 34)

    ANL-83-25

    AN--83-25

    DES3 014014

    ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue

    Argonne, Illinois 60439

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    PHYSICS DIVISION ANNUAL REVIEW

    1 APRIL 1982--31 MARCH 1983

    Donald S. Gemmell

    Division Director

    June 1983

    1id . . ph

    Preceding Annual Reviews

    ANL-80 -94 ANL-81-79 ANL-82-74

    1979-1980 1980-1981 1981-1982

  • FOREWORD

    The Physics Division Annual Review presents a

    broad but necessarily incomplete view of the research

    activities within the Division for the year ending in

    March 1983.

    At the back of this report a complete list of

    publications along with the Division roster can be

    found.

  • TABLE OF CONTENTS

    NUCLEAR PHYSICS RESEARCH

    Introduction 1

    1. MEDIUM-ENERGY PHYSICS RESEARCH 3

    A. STUDY OF PION REACTION MECHANISMS 5

    a. Study of the Pion Absorption Mechanism in 3 He 5 through the (Tr+,2p) and (1~, pn) Reactions

    b. Study of mow-Energy Pion Absorption in 3He 6

    c. Study of Pion Absorption Through the A(Tr,p)X 8 Reaction at T, = 500 MeV

    d. Survey of Inclusive Pion Scattering Near the A339 Resonance

    e. Inclusive Pion Charge-Exchange Reactions 11

    f. Isospin Dependence of the 18,160(7 , wo) Reactions 13

    g. Study of the (Tr,Irp) Reaction and Quasifree 15 Scattering in 4 He

    h. Measurement Near Threshold of 9Be(3He,IT) to the 15 A = 12 Isobaric Triplet by Recoil Detection

    i. The A Dependence of the (e,e'p) Reaction in the 16 Quasifree Region

    B. NUCLEAR STRUCTURE STUDIES 17

    a. Inelastic Scattering of Pions by 10B and 1B 17

    b. Inelastic Pion Scattering from 14 N 19

    c. Excitation of 8-, Particle-Hole States in 54Fe 20

    d. Iso alar Quenching in the Excitation of 8 States 22 in Cr

    e. Excitation of 8 States in 52Cr 22

    f. Polarized Proton Scattering from 26Mg 23

    V

  • Transverse Electron Scattering by 2 6Mg

    Inelastic Scattering of p + 48Ca at 160 MeV

    Study of the 4He(1~, r+) Reaction at Small Angles

    Discrete States from Pion Double-Charge-Exchange on Heavy Nuclei

    C. TWO-NUCLEON PHYSICS WITH PIONS AND ELECTRONS

    a. Energy and Angular Dependence of Tensor Polarization in Pion-Deuteron Elastic Scattering

    b. Tensor Polarization in Electron-Deuteron Elastic Scattering

    c. Feasibility Study of Electron Scattering Experiments with a Tensor Polarized Deuterium Target in an Electron Storage Ring

    d. Deuteron Tensor Polarimeter Development

    e. Photoneutron Physics

    D. WEAK

    a.

    b.

    c.

    d.

    e.

    f.

    g.

    h.

    INTERACTIONS

    Neutrino Oscillations at LAMPF

    Beta Decay of Polarized Nuclei and the Decay Asymmetry of 8Li

    A Test of V-A Positron Decay

    The Beta Decay Rate of 1 6 N(J - 0', 120 keV); Meson Exchange Currents and the Induced Pseudoscalar Coupling Constant

    0+ + 0- Beta Decay of 1 6 C Ground State

    The B anching Ratio to the 160 Ground State for the 19N Ground State

    Neutron Beta Decay

    Study of the 1 0 B(2-, 5.11 MeV) and lOB(2+, 5.16 MeV) Levels

    vi

    g."

    h.

    is

    is

    Page

    25

    25

    27

    27

    29

    29

    30

    32

    33

    33

    35

    35

    36

    39

    39

    40

    44

    45

    47

  • E. PARTICLE SEARCHES

    a. A Cryogenic Experiment for the Detection of Fractionally-Charged Particles

    b. A Search for Super-Heavy Particles in Cosmic Rays

    c. A Search for Axions from Nuclear Decays

    F. MEASUREMENT OF THE ELECTRIC DIPOLE MOMENT OF THE NEUTRON

    G. GeV ELECTRON MICROTRON

    a. Workshop on High-Resolution a'd Large-Acceptance Spectrometers

    b. Microtron Development

    II. RESEARCH AT THE TANDEM AND SUPERCONDUCTING LINAC ACCELERATOR

    A. HIGH ANGULAR MOMENTUM STATES IN NUCLEI

    a. Gamma Spectroscopy at Very High Spin in 147Gd

    b. Shape Change in 153Dy

    c. Lifetime Measurements in 154Dy

    d. Shape Changes at High Spin in 155Er

    e. Lif mc 5 easurements of Continuum States in ' Er

    f.

    g.

    h.

    i.

    j.

    Measurement of Feeding Times in 152Dy

    Yrast Population Patterns in a Wide Range of Nuclei

    The (nh11 /2) 6 Spectrum in 152Yb

    Spectroscopy of 100Cd

    Prolate and Oblate Rotational Bands in 186Hg

    vii

    Page

    49

    49

    50

    51

    53

    55

    58

    58

    59

    61

    61

    63

    64

    65

    66

    67

    67

    68

    69

    69

  • Page

    B. FUSION OF HEAVY IONS 73

    u. Fusion of 6 4Ni + 112, 11 4 ,116,1 1 8 ,1 2 0 ,12 2 ,1 2 4 Sn 73

    b. Fusion of 5 8Ni + 112,1 1 4,116, 1 1 8 ,12 0,12 2 ,12 4 Sn 75

    c. Fission of 6 4Ni + 112,114,116,118,120,122,1245n 75

    d. Delayed Alpha-Decay of Evaporation Residues Formed 77 in Fusion Reactions

    e. Atomic Charge States of Evaporation Residues 79

    f. Prompt Compound-Nuclear K X-rays in Fusion Reactions 79 Induced by a Heavy Projectile

    g. Suppression of Neutron Emission in "Cold" Heavy-Ion 80 Fusion

    C. REACTION MECHANISMS AND DISTRIBUTION OF REACTION 83 STRENGTHS

    a. Reactions o Resolved States of Nonfusion Channels 83 for 160 + 8Ca at Elab = 158.2 MeV

    b. Inelastic Scattering tpd Sine-Nucleon Transfer 83 Reactions Induced by 0 on Ca at Elab(1 0) = 150 MeV

    c. Measurement s of Evaporation Residues Produced 86 in 160 + 2 Mg at 4 S Elab(160) S 9.5 MeV/A

    d. Time-of-Flig~ Measurements of Evaporation Residues 88 Produced in Si-Induced Reactions

    e. Fusion Cross Section Measurements for 20Ne + 40Ca at 90

    Elab(2 0Ne) - 150 and 220 MeV

    f. Study of Direct Reactions in the System 37C1 + 20 8Pb 91 at Elab = 250 MeV

    g. Spectroscopic Studies of 23 4Th with the (180,160) 91 Reaction

    h. Large Neutro -Transfer Cross Sections Observed 94 in SNi and 8Ti Induced reaction on 208Pb

    i. Observation of Characteristic Gamma Rays from Quasi- 97 Elgtic and Deep-Inelastic Fragments in the 5 8Ni + Ni Reaction

  • Page

    D. ACCELERATOR MASS SPECTROMETRY 99

    a. Measurement of the Half-Life of 4 4 Ti via Accelerator 99 Mass Spectrometry

    b. Search for Doubly-Charged Negative Ions via 102

    Accelerator Mass Spectrometry

    c. Accelerator Mass Spectrometry of 4 1 Ca 103

    d. Measurement of the Half-Life of 6 0 Fe Using the 107 Tandem-Linac System as an Accelerator Mass Spectrometer

    E. SELECTED NUCLEAR SPECTROSCOPY AT THE TANDEM-LINAC 111

    a. Laser Spectroscopy of Radioactive Atoms 111

    b. Search for Transient Electric Field Gradient Acting 112 on Fast-Moving Ions in Solids

    c. The 7 Be(p,Y)8Be Reaction 112

    d. Resonances in 7Be(a,Y) and 7Li(a,Y) 114

    e. The 7Be Decay Branching Ratio 115

    F. EQUIPMENT DEVELOPMENT AT THE TANDEM-LINAC FACILITY 11

    a. Ray-Tracing Corrections for the Focal-Plane Counter 117 at the Spectrograph

    b. Test of the Large Focal-Plane Counter for the Linac 119 Magnetic Spectrograph

    c. A AE-E Detector for Fusion Measurements 119

    d. Modifications to the 65" Scattering Chamber for Long 120 Flight-Path Measurements

    e. The Y-ray Facility 120

    f. Superconducting Solenoid Lens Electron Spectrometer 121

    g. General-Purpose Beam Line 122

    h. Nuclear Target Making and Development 123

    ix

  • Page

    III. THEORETICAL NUCLEAR PHYSICS 125

    A. NUCLEAR FORCES AND SUBNUCLEON DEGREES OF FREEDOM 127

    a. Three-Body Forces in Light Nuclei and Nuclear Matter 128

    b. Present Status of the Nuclear Saturation Problem 130

    c. Studies of Three-Body Forces and Isobar Degrees of 130 Freedom in Nuclear Systems

    d. Nucleon-Nucleon Potentials with Isobars 134

    e. Consistency of Electromagnetic Current Operators and 136 Relativistic Wave Functions

    f. Relativistic Quantum Mechanics of Particles with 137 Direct Interactions

    g. Static Bag Source Meson Field Theory 137

    h. Monte Carlo Method for Chiral Bag Models 138

    B. VARIATIONAL CALCULATIONS OF FINITE MANY-BODY SYSTEMS 139

    a. Ground States of Quantal Many-Body Systems 139

    b. Monte-Carlo Variational Calculations of 4 He Droplets 140

    c. '-shell Hypernuclei and A-nucleon Interactions 142

    d. Alpha-Cluster Calculations of Be and Be 143

    C. NUCLEAR SHELL THEORY AND NUCLEAR STRUCTURE 145

    a. High Spin States in 91 Tc 145

    b. The 6~ States in 2 8Si 145

    c. Contribution of Giant Dipole State to Coulomb 146 Excitation of 6Li and 7 Li

    d. The Effect of the A(1236) on the g-facto:- of 147 Nucleons

    e. Beta Decay of 160(0+) to 16 N(0-) 147

    f. Analysis of Inelastic Scattering of Pions 149

    x

  • Page

    D. INTERMEDIATE ENERGY PHYSICS 151

    a. Phenomenological Many-Body Hamiltonian for Pions, 151 Nucleons, and A Isobars

    b. A Microscopic Study of A-Nucleus Dynamics 152

    c. Absorption of Pions by the A = 3 Nuclei 155

    d. Electroproduction of A from Light Nuclei 155

    e. A Nonstatic DWIA Model for Pion Scattering 157

    f. Production of Hypernuclei by Few GeV Electro