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Strong $Λπ$ Phase Shifts for CP Violation in Weak $Ξ\rightarrow Λπ$ Decay

Ming Lu·Martin J. Savage·Mark B. Wise
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Abstract

Strong interaction $Λπ$ phase shifts relevant for the weak nonleptonic decay $Ξ\rightarrow Λπ$ are calculated using baryon chiral perturbation theory. We find in leading order that the S-wave phase shift vanishes and the $J={1 \over 2}$ P-wave phase shift is $-1.7 ^{\rm o} $. The small phase shifts imply that CP violation in this decay will be difficult to observe. Our results follow from chiral $SU(2)_L\times SU(2)_R$ symmetry.

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Ming Lu, Martin J. Savage, Mark B. Wise. 1994-07-08. Strong $Λπ$ Phase Shifts for CP Violation in Weak $Ξ\rightarrow Λπ$ Decay. https://doi.org/10.1016/0370-2693(94)91456-7

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