p̄p low energy parameters from annihilation cross section data
نویسنده
چکیده
Abstract. The recent experimental data obtained by the OBELIX group on total p̄p annihilation cross section are analysed; the low energy spin averaged parameters of the p̄p 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 Imasc = −0.69±0.01(stat)±0.03(sys) fm, ImAsc = −0.76±0.05(stat)± 0.04(sys) fm. The results are in very good agreement with existing atomic data. The recent experimental data obtained by the OBELIX group on total p̄p annihilation cross section are analysed; the low energy spin averaged parameters of the p̄p 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 Imasc = −0.69±0.01(stat)±0.03(sys) fm, ImAsc = −0.76±0.05(stat)± 0.04(sys) fm. The results are in very good agreement with existing atomic data. Published in Physics Letters B 397 (1997) 345−349
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