Quark Model for Photoproduction of Baryons
Abstract
A quark (Q) model of photoproduction of positive and negativeparity baryons in association with a meson octet is proposed. According to this model, the basic mechanism for photoproduction is represented by a Uspininvariant process γ+Q>Q+Π at each quark, Π being a meson octet. The matrix elements of this basic amplitude are taken between appropriate 3Q states representing the initial proton and a final baryon, according to the multiplet structure 56^{+} of SU(6) and (70,(70,3)^{} of SU(6)⊗O(3) for the positiveparity and negativeparity baryonic states, respectively. The SU(3) sum rules based on Uspin invariance of the amplitudes are verified. Several additional sum rules, valid separately for spinflip and nonspinflip amplitudes, are derived for the 56^{+} states. For the negativeparity states, a number of nontrivial sum rules connecting different SU(3) multiplets are obtained.
 Publication:

Physical Review
 Pub Date:
 April 1967
 DOI:
 10.1103/PhysRev.156.1581
 Bibcode:
 1967PhRv..156.1581G