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\bar{p}p low energy parameters from annihilation cross section data

J. Carbonell·K. V. Protasov·A. Zenoni
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Abstract

The recent experimental data obtained by the OBELIX group on total $\bar{p}p$ annihilation cross section are analysed; the low energy spin averaged parameters of the $\bar{p}p$ scattering amplitude (the imaginary parts of the S-wave scattering length and P-wave scattering volume) are extracted from the data. Their values are found to be equal to $Im a_{sc} = - 0.69 \pm 0.01 (stat) \pm 0.03 (sys) fm, Im A_{sc} = - 0.76 \pm 0.05 (stat) \pm 0.04 (sys) fm^3$. The results are in very good agreement with existing atomic data.

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J. Carbonell, K. V. Protasov, A. Zenoni. 1998-06-10. \bar{p}p low energy parameters from annihilation cross section data. https://doi.org/10.1016/s0370-2693(97)00190-1

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