pi N and pi pi N couplings of the Delta(1232) and its chiral partners
We investigate the interactions and chiral properties of the four spin-3/2 baryons N(-)(D(13)), N(+)(P(13)) Delta(+)(P(33)), and Delta(-)(D(33)) together with the nucleon. We construct the SU(2)(R) X SU(2)(L) invariant interactions between the spin-1/2 and spin-3/2 baryons with the aid of a new, specially developed spin and isospin projection technique for these baryon fields, where the chiral invariant interactions contain one- and two-pion couplings. We obtain simple relations for the coupling constants of the one- and two-pion spin-1/2-1/3 transitions terms. The relation for the one-pion interactions reasonably agrees with the experiments, which suggests that these spin-3/2 baryons are chiral partners.
Source:Physical Review Letters, 2008, 101, 9
- the National Science Council (NSC) of Republic of China [NSC96-2119-M-002-001]