A = 4 0/sup +/ - 1/sup +/ binding-energy difference

Conference · Fri Jan 01 04:00:00 EST 1982

OSTI ID:5195127

Gibson, B F; Lehman, D R

The A = 4 ..lambda..-hypernuclei provide a rich source of information about the s-wave properties of the fundamental hyperon-nucleon (YN) force as well as offer a unique opportunity to investigate the complications that arise in calculations of the properties of bound systems in which one baryon (here the ..lambda..) with a given isospin couples strongly to another (the ..sigma..) with a different isospin. The ..lambda../sup 4/H - ..lambda../sup 4/He isodoublet ground-state energies are not consistent with a charge symmetry hypothesis for the YN interaction. The (spin-flip) excitation energies are quite sensitive to the ..lambda..N - ..sigma..N coupling of the YN interaction. In particular, when one represents the free YN interaction in terms of one-channel effective ..lambda..N potentials, the resulting 0/sup +/ (ground) state and 1/sup +/ (excited) spin-flip state are inversely ordered in terms of binding energies, the 1/sup +/ state being more bound. It is the ..sigma.. suppression that results from the reduced strength of the ..lambda..N - ..sigma..N off-diagonal coupling potential when the trinucleon core is restricted to isospin-1/2 which we study here. We find this spin-isospin suppression of the ..lambda..-..sigma.. conversion, which is due to the composite nature of the nuclear cores of the ..lambda../sup 4/H and ..lambda../sup 4/He hypernuclei, to be a significant factor in understanding the 0/sup +/ - 1 /sup +/ binding energy relationship.

• Research Organization: Los Alamos National Lab., NM (USA); George Washington Univ., Washington, DC (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5195127
• Report Number(s): LA-UR-82-1744; CONF-820635-4; ON: DE82017589
• Country of Publication: United States
• Language: English

Related Subjects

645201* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- General & Scattering Theory
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BINDING ENERGY
COUPLING
ELEMENTS
ENERGY
ENERGY LEVELS
FLUIDS
GASES
GROUND STATES
HELIUM
HYDROGEN
HYPERNUCLEI
ISOSPIN
NONMETALS
NUCLEAR FRAGMENTS
NUCLEI
PARTIAL WAVES
PARTICLE PROPERTIES
RARE GASES
S WAVES