ABSTRACT

X → 1 + 2 find the distribution of secondary particles on the angle of their divergence in the lab frame if in the rest frame of the X-particle at m1 = m2 the decay has an isotropic character. 2.9. Two particles with the isospins I = 1/2 and I = 1 make up a coupled state. Us-

ing the properties of the lowering and rasing isospin operators S (is) ± = S

isospin wavefunctions for the following states: Ψ(3/2, 1/2),Ψ(3/2,−1/2),Ψ(1/2, 1/2) where Ψ(I, I3) is a wavefunction of a system with the total isospin I and the projection I3. 2.10. Taking into account the f1(1420)-resonance spin to be equal to zero, define isotopic relations between strong decay probabilities of the f1(1420)-resonance through the channels:

f → K0K+ + pi−, f → K0K− + pi+,

f → K+K− + pi0, f → K0K0 + pi0. Thinking the C-parity of f(1420) to equal +1, point out the basic peculiarities of detecting the third decay channel. 2.11. Allowing for the isospin conversation law in the strong interaction, find the ratio of the total cross sections for the following reactions:

p+ p→ d+ pi+, n+ p→ d+ pi0.