Abstract
The pp annihilation cross-sections at 66.4-68.9-71.4 MeV/c have been measured using the presently instrumented part of the OBELIX spectrometer. The results have been obtained at p energies ( ≃ 2.5 MeV) by one order of magnitude smaller than in any existing experiment concerning the in-flight antiproton-proton annihilation. The average value obtained over the total interval 65.1-72.5 MeV/c, βσanT = 33.2 ± 1.7 (stat.) ±1.8 (syst.) mb, in agreement with a specific calculation, would favour for the spin-averaged S-wave scattering length the value (-0.7 + i0.8) fm. The branching ratios for the annihilations in two, four and six charged mesons turn out to be quite similar to those for annihilation at rest in liquid hydrogen.
Lingua originale | Inglese |
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pagine (da-a) | 349-353 |
Numero di pagine | 5 |
Rivista | Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics |
Volume | 256 |
Numero di pubblicazione | 3-4 |
DOI | |
Stato di pubblicazione | Pubblicato - 14 mar 1991 |
Pubblicato esternamente | Sì |