Comment:

Part (a) is a typical problem involving breaking of the flavor SU(3) symmetry of the light quark states. The number of states in an approximate multiplet is unchanged from the symmetrical situation. Here the 1 and the the I = 0 component of the 8 of the original nonet mix because of the difference between the masses of the s quark and the u and d quarks.

Part (b) deals with the space and spin structure of the states in the nonet, and the translation of information obtained experimentally into information about the quark wave functions.

Comment:

This problem completes the analysis started in Prob. 2. Use the information on the spin and parity of the decay products given there, or better, look it up in the Review of Particle Properties to get some familiarity with the summary tables of meson properties. The problem illustrates the different descriptions the angular momentum of the a_2 in terms of its quark structure, and in terms of its decay products.

Comment:

This is a typical example of the use of the approximate SU(3) symmetry of the light quark states to obtain testable predictions for cross sections or decays. The relations here should hold at energies far enough above the reaction thresholds that mass differences are small on the scale of the available energy in the center of mass system. Why is this the relevant energy?

 

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© 1996, Loyal Durand