ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING 100039,PEOPLES R CHINA
; NANKAI UNIV,DEPT PHYS,TIANJIN 300071,PEOPLES R CHINA
We study the CP non-invariance in the DELTAs = 1 weak radiative decay SIGMA+ --> Pgamma based on a few widely-discussed models. In the work, we study the isospin zero channel of the photon where unlike for SIGMA --> Ppi, the CP non-invariance in SIGMA --> Pgamma is caused by the interference of the strong interaction to the weak-electromagnetic process through loops. We obtain a CP factor R = (alpha - alphaBAR)/(a + alphaBAR) of an order approximately 10(-5) to approximately 10(-4) which may be observed in the future.