Parity-Violating Photoproduction of π± on the Δ Resonance
We analyze the real-photon asymmetry Aγ± for the parity-violating (PV) π± production on the Δ resonance via the reactions γ→+p→Δ+→π++n and γ→+d→Δ0+p→π-+p+p. This asymmetry is nonvanishing due to a PV γNΔ coupling constant, dΔ±. We argue that an experimental determination of this coupling would be of interest for hadron dynamics, possibly shedding light on the S-wave/ P-wave puzzle in the hyperon nonleptonic decays and the violation of Hara's theorem in weak radiative hyperon decays.
Additional Information© 2001 The American Physical Society Received 20 June 2001; published 29 October 2001 This work was supported in part under U.S. Department of Energy Contracts No. DE-AC05-84ER40150 and No. DE-FGO2-00ER41146, the National Science Foundation under award No. PHY98-01875, and a National Science Foundation Young Investigator Award. C. M. M. acknowledges support from FAPESP (Brazil), Grant No. 99/00080-5. We thank K. Gustafsson, T. Ito, J. Martin, and R. McKeown for helpful discussions.
Published - ZHUprl01.pdf