A theory of hyperfragments

Journal Article · Fri Dec 01 00:00:00 EST 1961 · Nuovo Cimento

DOI:https://doi.org/10.1007/bf02786889· OSTI ID:4050219

Iwao, Syurei ^[1]

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1. Univ. of Rochester, NY (United States)

Mesic decay of hyperfragments is discussed systematically on the basis of our previous model for hyperfragments. The general formalism for the two-body and three-body mesic decay is developed. The polarization-direction correlation and the angular correlation, for the two-body and the three-body decays are discussed together with the decay probability. The formalism is developed so as to include the isotopic spin selection rule (ΔI = 1/2 and 3/2) for the mesic decays. The theory developed here is applied especially for the low mass number hyperfragments where we found that the branching ratios of the two-body and the three-body mesic decays of ³H_Λ and ⁴H_Λ, (³H_Λ→³He+π^-)/(³H_Λ → D + p + π^-) and (⁴H_Λ→ ⁴He + π^-)/(^4H _Λ →³H + p + π^-), can be used for the determination of the spins of both hyperfragments. The fraction of the p-wave decay rate for the free Λ decay obtained from the ⁵He_Λ→⁴He + p + π^- where the decay proceeds through two resonant states (p3/2 and p1/2) is given by p²/(s² + p²) ≈ .4 which gives spin zero of ⁴H_Λ in connection with the Dalitz and Liu plot and hence odd parity for the kaon. The decay rate of the charged and the neutral mode is always 2/1 if, and only if, the condition obtained by Okubo, Marshak and Sudarshan is satisfied. And finally we show that the final state interaction for the two-body mesic decay can be described by the pion and residual nucleus scattering phase shifts by making use of the invariance of the total S-matrix of the decay processes under the Wigner (weak) time reversal.

• Research Organization: Univ. of Rochester, NY (United States)
• Sponsoring Organization: US Atomic Energy Commission (AEC)
• NSA Number: NSA-15-014946
• OSTI ID: 4050219
• Report Number(s): NYO--9679
• Journal Information: Nuovo Cimento, Journal Name: Nuovo Cimento Journal Issue: 6 Vol. 22; ISSN 0029-6341
• Publisher: Società Italiana di Fisica
• Country of Publication: United States
• Language: English

Related Subjects

ANGULAR DISTRIBUTION
BRANCHING RATIO
CONSERVATION LAWS
DECAY
DEUTERIUM
FIELD THEORY
GROUP THEORY
HELIUM 3
HELIUM 5
HYDROGEN 4
HYPERFRAGMENTS
INTERACTIONS
INVARIANCE PRINCIPLE
ISOSPIN
KAONS
LAMBDA PARTICLES
MANY BODY PROBLEM
MATRICES
MESONS
NUCLEI
OKUBO MASS FORMULA
P-WAVE
PARITY
PIONS
POLARIZATION
PROTONS
QUANTUM MECHANICS
RELATIVITY THEORY
RESONANCE
S-MATRIX
SCATTERING
SELECTION RULES
SPIN
STRANGE PARTICLES
STRONG INTERACTIONS
TIME REVERSAL
TRANSIENTS