On the “Spurion” Theory of Strange Particles.
In the nonlinear spinor theory which only involves spinor-isospinor field operators, strange-particle states may be constructed under the assumption of a ground state un symmetrical with respect to isospin: « spurions » carrying isospin can be detached from the ground state and attached to systems constructed from local field operators to form strange particles. In addition to isospin, further properties have to be attributed to the spurions to be consistent with the requirements of Lorentz- and CPT-invariance of the vacuum. Three such possibilities present themselves: The first possibility which adds a parity property has been considered in an earlier paper. Its group-theoretical implications (e.g., odd ΛΣ-parity) are in contradiction to present experimental evidence; therefore this possibility is ruled out. Hence the second possibility, which adds a hypercharge property, is studied in the present paper. The spurion systems then transform according to representations of U 2 . One finds that the combination I(I + 1) - 1/4 Y 2, known in connection with broken SU 3, appears automatically in the factor multiplying the eigenvalue operator for the simplest bosons due to the characteristic form of the field equation and the permutation properties of the spurions. The eigenvalue operators of baryons of spin 1/2 are multiplied by a factor containing aBY + b [I(I + 1) — 1/4 Y 2 ] (B = baryon number) if the simplest bosons are taken into account in the self-interact ion. Although the I, Y operators of the broken SU 3 appear, the group SU 3 is never assumed nor established, and hence the characteristic grouping of particles into 1, 8, 10 etc. cannot be derived group-theoretically. It is interesting, however, to observe that a grouping of 8 for the simplest bosons follows naturally from dynamical considerations.
Unable to display preview. Download preview PDF.
- (2).H. P. DüRR AND J. GéNéNIAU: Proc. of the 1962 Internat. Conf. on High-Energy Physics at CERN. p. 681.Google Scholar
- (6).H. P. DüRR AND W. HEISENBERG: Strange particle coupling constants, preprint, Max-Planck-Institut für Physik and Astrophysik, München (November 1964).Google Scholar
- (8).J. DHAR AND Y. KATAYAMA: presented at The Internat. Conf. on High Energy Physics at Dubna (1964),Google Scholar
- (9).J H. DAVID AND A. DEREM: Etude des fonctions L, M, N de la théorie spinorielle nonlinéaire des particules élémentaires, preprint Université Libre Bruxelles.Google Scholar