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p p annihilation cross sections into 2-, 4- and 6-prong topologies, and the exclusive annihilation cross sections for the π + π − , K + K − , π + π − π 0 , π + π + π − π − , π + π + π − π − π 0 , π + π + π + π − π − π − , and π + π + π + π − π − π − π 0 channels in the momentum range 374–680 MeV/ c were measured. No prominent structure was observed in the momentum dependence of any of the above cross sections, but a small enhancement in the cross section was observed at 490 MeV/ c corresponding to the S meson mass in the topological, and π + π − π 0 and π + π + π − π − π 0 cross sections. If the extensive of the S meson with a mass and width of 1935.5 and 2.8 MeV/ c 2 is assumed, our measurement gives a total resonant annihilation cross section into charged particles of 10.0±3.0 mb.

8 data tables

Table 1

FIRST CROSS SECTION IS CHARGED ANNIHILATION CROSS SECTION AND IS THE SUM OF THE 2, 4, AND 6PRONG.

Table 2

Table 3

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CHARGED PARTICLE AND PI0 MULTIPLICITY DISTRIBUTIONS AND THE ANNIHILATION PROPERTIES OF ANTI-P P INTERACTIONS AT 70-GeV/c

Dumont, J.J. ; Lemonne, J. ; Vanhomwegen, G. ; et al.

Z.Phys.C 13 (1982) 1-9, 1982.

Inspire Record 179759 DOI 10.17182/hepdata.16433

The elastic and inelastic$\bar p$p cross sections at 70 GeV/c have been determined in an experiment performed at CERN using BEBC equipped with a TST. The topological cross sections were measured and the moments of the inelastic multiplicity distribution are 〈nc〉=6.16±0.09, 〈nc〉/D=2.04±0.05 andf2cc=2.97±0.03. The average number of Dalitz pairs per inelastic event is (3.12±0.09)×10−2. Assuming that these all arise from π0 decay the average π0 multiplicity is$\langle n_{\pi ^0 } \rangle= 2.71 \pm 0.14$. The$\bar p$p−pp cross section differences lead to an annihilation cross section σA = 4.42±0.41 mb and the moments of the annihilation multiplicty distribution are 〈nA〉=8.0±0.3, 〈nA〉/D=2.5±0.2 andf2A−−=−1.4±0.3. An independent check of σA was made by investigating fast forward charged and neutral secondary interactions in the TST and in the surrounding neon-hydrogen mixture, and gives a value σA = 5.0±1.6 mb. The ratio of fast$\bar n$ to$\bar p$ production in non-annihilation interactions at 70 GeV/c is found to be 0.45±0.11.

9 data tables

Table 1

No description provided.

Table 2

INELASTIC TOPOLOGICAL CROSS SECTIONS. NORMALIZED TO TOTAL INELASTIC CROSS SECTION OF 35.7 +- 0.5 MB (AYRES ET AL., PR D15, 3105).

Table 3

No description provided.

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GENERAL FEATURES OF ANTI-P P INTERACTIONS AT 7.3-GEV/C

Patel, G.D. ; Johnson, P. ; Mason, P. ; et al.

Z.Phys.C 12 (1982) 189-202, 1982.

Inspire Record 179888 DOI 10.17182/hepdata.2239

Absolute inclusive cross sections for$\bar pp$ interactions at 7.3 GeV/c are given. The data cover prong cross sections,V0, γ production and inclusive charged particle (p/π) production. Separation has been made into annihilation and non-annihilation components. Inclusive π+, π− production in the processes of$\bar pp$ annihilation and non-annihilation are compared with simple quark models.

26 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

ANNIHILATION AND NON-ANNIHILATION TOPOLOGICAL CROSS SECTIONS.

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Four-pion final state in anti-p p annihilations at 940 mev/c

Burns, R.R. ; Condon, P.E. ; Donahue, J. ; et al.

Nucl.Phys.B 27 (1971) 109-124, 1971.

Inspire Record 68769 DOI 10.17182/hepdata.33655

Resilts are reported on the four-pion final state from antiproton annihilations in hydrogen in the vicinity of 940 MeV/ c . The cross section for π − π − π + π + is found to be 3.6 mb. Abundant resonance production is observed, with fits indicating that quasi-two-body production constitutes approximately half the four-pion events. The model employed, which includes resonance production and Bose symmetrization, yields excellent fits to mass distributions and angular correlations.

2 data tables

Table 1

ASSUMING TOTAL AP P CROSS SECTION OF 122 MB. ERRORS INCLUDE SYSTEMATIC UNCERTAINTIES.

Table 2

ANALYSIS OF 4PION FINAL STATE. FIXED MASS AND WIDTH BREIT-WIGNER RESONANCES AND BACKGROUND FITTED TO DATA. CROSS SECTIONS CALCULATED BY PDG (COMPILATION PDG3). ERROR GIVEN IS SCATTER FROM VARIOUS FITS.

Measurement of the proton-antiproton total annihilation cross section at low energy

Cline, D. ; English, J. ; Reeder, D.D. ;

Phys.Rev.Lett. 27 (1971) 71-74, 1971.

Inspire Record 68958 DOI 10.17182/hepdata.21462

The p¯p total inelastic cross section has been measured in a hydrogen bubble chamber for p¯ momenta from 100 to 550 MeV/c. Below 200 MeV/c the cross section increases rapidly to several barns. From this behavior it is inferred that high partial waves, perhaps to L=3, are important in the annihilation at the lowest momenta studied. An abrupt change in the momentum dependence of the total absorption cross section occurs at about 350 MeV/c in the vicinity of previously observed structure in backward elastic scattering.

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.