The Weak Decay of Hypernuclei

  • C. Bennhold
  • A. Parreño
  • A. Ramos
Part of the Few-Body Systems book series (FEWBODY, volume 9)


The nonmesonic weak decay of light Λ hypernuclei is investigated in a shell model framework. The strangeness-changing weak ΛN → N N transition potential is constructed by including the exchange of the pseudoscalar mesons π, K, η as well as the vector mesons ρ, ω, and K*, whose weak coupling constants are obtained from soft meson theorems and SU(6)w. The transition matrix element includes a realistic ΛN short-range correlation function that is based on the Nijmegen Y N-potential. The total decay rate and the proton asymmetry, which represents a measure of the parity-violating to parity-conserving amplitudes, are in agreement with present experimental errors while the neutron- to proton-induced ratio is underestimated by more than a factor of two. In general, the observables are found to be dominated by the pion-exchange mechanism since the contributions of heavier mesons are suppressed by form factors and short-range correlations.


Form Factor Vector Meson Weak Decay Heavy Meson Tensor Interaction 


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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • C. Bennhold
    • 1
  • A. Parreño
    • 2
  • A. Ramos
    • 2
  1. 1.Center of Nuclear Studies, Department of PhysicsThe George Washington UniversityUSA
  2. 2.Dept. ECMFacultat de FísicaBarcelonaSpain

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