G. Bendiscioli

Antiproton-helium annihilation around 45 MeV/c

Abstract The p ¯ 4 He annihilation cross section averaged over the interval 40–50 MeV/c has been measured using a streamer chamber in a magnetic field. The measured value is 1342±250 mb. It agrees with a behaviour like 1/p of the annihilation cross section. Our result has been obtained at the lowest momentum achieved till now in measurements of antiproton annihilation in flight.

Determination of the p̄-neutron scattering amplitude from p̄-nucleus elastic scattering data

Abstract The elastic scattering data of p on 12C, 16O and 40Ca nuclei at incident energies of 47 and 179 MeV are fitted with a Glauber model. The best fit procedure determines both the parameters of the p-neutron scattering amplitude and the degree of accuracy of the model. It is found that the theory holds well at 179 MeV, whereas it seems to be slightly inaccurate at 47 MeV. The comparison with the results on the p-neutron interaction obtained in other works is also performed.

anti-p He-3 REACTION CROSS-SECTION AT 200-MeV/c

Abstract Inelastic p - 3 He events at 192.8 MeV/ c are detected with a self-shunted streamer chamber. The measured reaction cross section is 392±23.8mb. This result is briefly discussed and compared with other reaction cross sections for low-energy p with light nuclei.

Restriction on amount of antimatter in the early universe from\(\bar p^{ - 4} \)He reaction data-4He reaction data

SummaryA limit on the possible amount of antimatter in the early universe has been deduced from

Experimental results on antiproton interaction with nuclei obtained in the PS179 CERN experiment at LEAR

\bar p^{ - 4}

Remarks on the branching ratios of antinucleon-nucleon annihilations into two mesons

He reaction data obtained at 180 MeV.

Glauber theory analysis of antiproton-4He elastic scattering at 607MeV/c

Abstract The annihilation fractions of the p p annihilation at rest into ππ , πη , ηη , φπ 0 , K K and η (1440) ππ at different target densities are reviewed in order to determine their branching ratios from S and P antiprotonic atom sublevels and the sublevel population fractions. Particular emphasis is given to the incompatibility of some annihilation fraction measurements and to the expected dependence of the p p atom sublevel population fractions on the target density. The population fraction of the 3 P 0 sublevel in liquid target turns out to be higher than its statistical weight.

Glueball candidates seen in the reactions bar p 20Ne and bar p 4He at 607 MeV/c

Information recently obtained by the PS179 (STREAMER) collaboration at LEAR on p4He elastic scattering, strangeness production in antiproton annihilation at rest and p annihilation in nuclear photo‐emulsion is presented.