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

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 $Im{a}_{sc}=-0.69\pm 0.01(stat)\pm 0.03(sys)fm,Im{A}_{sc}=-0.76\pm 0.05(stat)\pm 0.04(sys)f{m}^3$. The results are in very good agreement with existing atomic data.

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