On the determination of the parity of the ${\Theta }^{+}$

Abstract

We critically examine the possibility of determining the parity of the ${\Theta }^{+}(1540)$ from the reactions $NN\to {\Theta }^{+}Y$ ($Y$ = $\Lambda$, $\Sigma$) recently discussed in the literature. Specifically, we study the energy dependence of those observables that were suggested to be the most promising ones to unravel the parity of the ${\Theta }^{+}$, namely the spin correlation coefficient $A_{xx}$, and the spin transfer coefficient $D_{xx}$. We show that the energy dependence of ${\sigma }_0(1+A_{xx})$, corresponding to the spin-triplet production cross section, guarantees unambiguous information on the parity of the ${\Theta }^{+}$. Here, ${\sigma }_0$ denotes the unpolarized cross section. Also, the possibility to determine the parity of the ${\Theta }^{+}$ through the energy dependence of ${\sigma }_0{D}_{xx}$ is discussed.

13 pages, 6 figures

References in corpus (5)

• New results on the limit for the width of the exotic Theta^+ resonance
• Why the Theta+ is seen in some experiments and not in others - a possible explanation
• Spin observables and the determination of the parity of ${\Theta }^{+}$ in photoproduction reactions
• Glueballs, Hybrids, Pentaquarks : Introduction to Hadron Spectroscopy and Review of Selected Topics
• From pions to pentaquarks

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• Possibility of determinig the parity of the pentaquark ${\Theta }^{+}$ from photoproduction near threshold
• Positive parity pentaquark towers in large Nc QCD
• Structure and reactions of pentaquark baryons
• Antikaon angular distributions in the reaction $\gamma d\to K^{-}{\Theta }^{+}p\to K^{-}{K}^{+}np$ near the threshold and the parity of the ${\Theta }^{+}$ pentaquark
• Spin correlations in the reaction "pi \vec D --> \vecΣΘ^+" and the parity of Theta^+
• Hadronic production of eta--mesons: recent results and open questions
• Angular distribution and azimuthal asymmetry for pentaquark production in proton-proton collisions
• Remarks on the parity determination of narrow resonances