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How to measure the parity of the $Θ^+$ in $\vec p\vec p$ collisions

C. Hanhart·M. Büscher·W. Eyrich·K. Kilian·U. -G. Meißner·F. Rathmann·A. Sibirtsev·H. Ströher
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Abstract

Triggered by a recent paper by Thomas, Hicks and Hosaka, we investigate which observables can be used to determine the parity of the $Θ^+$ from the reaction $\vec p\vec p \to Σ^+Θ^+$ near its production threshold. In particular, we show that the sign of the spin correlation coefficient $A_{xx}$ for small excess energies yields the negative of the parity of the $Θ^+$. The argument relies solely on the Pauli principle and parity conservation and is therefore model--independent.

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C. Hanhart, M. Büscher, W. Eyrich, K. Kilian, U. -G. Meißner, F. Rathmann, A. Sibirtsev, H. Ströher. 2004-01-19. How to measure the parity of the $Θ^+$ in $\vec p\vec p$ collisions. https://doi.org/10.1016/j.physletb.2004.03.065

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