Asymmetry measurements in antiproton-proton annihilation into two mesons at low energies

doi:10.1016/0920-5632(89)90214-4

Nuclear Physics B - Proceedings Supplements

Volume 8, June 1989, Pages 141-148

F. Tessarotto

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Abstract

Analysing power and differential cross-section have been measured for the reactions $p p →π^{−} π^{+}, p p →K^{−} K^{+}$ by the SING Collaboration (PS172) at LEAR, using a polarized target. Preliminary results of A_on are presented, at 12 momenta from 500 to 1500 MeV/c. They show very large asymmetries, and a remarkable variation with energy in the newly explored low momentum region.

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Cited by (7)

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We present an illustrative analysis to show that a simple relation between the helicity-flip and helicity-nonflip partial-wave amplitudes can account for the strikingly large asymmetries observed in the $p p → π^{−} π^{+}$ and $p p → K^{−} K^{+}$ reactions. Our study supports the argument that the final K⁻K⁺ state originates from a more central reaction than the π⁻π⁺ final state. The rather general nature of our approach leads to the expectation that the large asymmetries are likely to persist at higher energies until the perturbative QCD regime sets in.
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¹: Present address: University of Iowa, Iowa City IA, USA

²: Present address: DPNC, University of Geneva, Geneva, Switzerland

³: Present address: BNL, Upton NY, USA

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Nuclear Physics B - Proceedings Supplements

Abstract

References (12)

Phys. Lett.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Cited by (7)

Maximum asymmetry phenomena in pp → π<sup>-</sup>π<sup>+</sup> and pp → K<sup>-</sup>K<sup>+</sup> reactions

Differential cross sections and analysing powers for PP → π<sup>-</sup>π<sup>+</sup> and K<sup>-</sup>K<sup>+</sup> from 360 to 1550 MeV/c

NN interaction theoretical models

The role of final-state interactions in the p̄p→π<sup>+</sup>π<sup>-</sup> annihilation process

Left-right asymmetry in p̄p→π-π+

Low energy antiproton physics