Whitmore, J.
PBAR P --> PI- PI+
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Elastic Scattering of Charged Mesons, Anti-protons and Protons on Protons at Incident Momenta of 20-{GeV}/$c$, 30-{GeV}/$c$ and 50-{GeV}/$c$ in the Momentum Transfer Range $0.5-{\rm GeV}/c^2 < -t < 8-{\rm GeV}/c^2$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Bock, R. ; et al.
Nucl.Phys.B 255 (1985) 273-327, 1985.
Inspire Record 206292 DOI 10.17182/hepdata.33789

Results are presented from experiment WA7 at the CERN SPS, which has measured the elastic differential cross sections of π ± p, K ± p, p p and pp at incident momen ta of 20, 30 and 50 GeV/ c . The measurements cover the momentum transfer range 0.5 < | t | < 8 (GeV/ c ) 2 , corresponding to c.m. scattering angles between 10° and 50°. The experimental set-up, trigger logic and data analysis are described. The experimental results are compared with existing meson-proton and nucleon-proton data at lower and higher energies covering the medium- and large-| t | region. Some prominent models and their predictions for elastic scattering at WA7 energies and beyond are reviewed, with emphasis on geometrical scaling, factorizing eikonal models, lowest-order QCD and other dynamical exchange-type models. Results for p p two-body annihilation into π − π + and K − K + at 30 and 50 GeV/ c , obtained in parallel with the elastic p p data, are also presented.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Proton-antiproton annihilation into pi+ pi- and k+ k- from 700 to 1100 mev/c

Mandelkern, M.A. ; Burns, R.R. ; Condon, P.E. ; et al.
Phys.Rev.D 4 (1971) 2658-2666, 1971.
Inspire Record 74756 DOI 10.17182/hepdata.23118

Total and differential cross sections are presented for proton-antiproton annihilation into π+π− and K+K− at six laboratory momenta between 686 and 1098 MeV/c. The two-pion final state displays moderate energy dependence in its differential cross section, but shows no evidence of any direct-channel resonances. In contrast, the two-kaon final state exhibits some behavior in the total and differential cross section suggestive of a possible direct-channel effect between 800 and 1000 MeV/c.

3 data tables
Table 1

NOTE CUT EXCLUDES LARGE FORWARD CROSS SECTION.

Table 2

LEGENDRE COEFFICIENTS NORMALIZED TO LEGN(L=0) = 0.5.

Table 3

LEGENDRE COEFFICIENTS NORMALIZED TO LEGN(L=0) = 0.5.


Observations on anti-p d annihilations at rest into two pions

Gray, L. ; Papadopoulou, T. ; Simopoulou, E. ; et al.
Phys.Rev.Lett. 30 (1973) 1091-1094, 1973.
Inspire Record 84510 DOI 10.17182/hepdata.21409

The ratio (p¯d→π−π0ps)(p¯d→π−π+n) at rest, with spectator momenta ≲300 MeVc, has been measured and found to be 0.68 ± 0.07. This implies that (75 ± 8)% of the annihilations in deuterium into two pions come from odd N¯N orbital angular momenta, in disagreement with the S-state-dominance hypothesis. It has also been observed that the p¯d→π−π0ps production rate depends on the spectator momentum, which suggests energy-sensitive N¯N phenomena near threshold.

1 data table
Table 1

RELATIVE ANNIHILATION FREQUENCY AT REST.


EXCLUSIVE ANNIHILATION PROCESSES IN 8.8-GEV ANTI-P P INTERACTIONS AND COMPARISONS BETWEEN ANTI-P P NONANNIHILATIONS AND P P INTERACTIONS

Ward, D.R. ; Simmons, A.J. ; Ansorge, R.E. ; et al.
Nucl.Phys.B 172 (1980) 302, 1980.
Inspire Record 158992 DOI 10.17182/hepdata.34487

We give cross sections for annihilation and non-annihilation reactions in p p interactions at 8.8 GeV. The non-annihilation data are compared with pp data from the same experiment. We compare data on resonance production and on the impact parameter structure of the final states in p p annihilation and non-annihilation and pp interactions. We investigate the charge structure of the 2 π + 2 π − π 0 final state, and find it consistent with a simple quark model.

4 data tables
Table 1

NORMALIZED TO A TOTAL AP P CROSS SECTION OF 55.9 MB. ANNIHILATION CROSS SECTIONS.

Table 2

NORMALIZED TO A TOTAL AP P CROSS SECTION OF 55.9 MB. NON-ANNIHILATION CROSS SECTIONS.

Table 3

NORMALIZED TO A TOTAL P P CROSS SECTION OF 40.0 MB.

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Comparison of new data on anti-p p --> pi- pi+ and other two meson states at 2.3-gev/c

Fields, T. ; Cooper, W.A. ; Rhines, D.S. ; et al.
Phys.Lett.B 40 (1972) 503-506, 1972.
Inspire Record 75681 DOI 10.17182/hepdata.28267

Complete angular distributions for the reactions p p → π − π + and other two meson states at 2.3 GeV/ c are presented. The extraordinary π − π + angular distribution is contrasted with the other final states and the predictions of simple models. A favourable comparison is made with the qualitative features of a dual model involving high mass meson states with a strong degeneracy with respect to I -spin.

2 data tables
Table 1

SOME ANGULAR DISTRIBUTIONS ALSO PRESENTED.

Table 2

K* NEUTRAL TO CHARGED PRODUCTION RATIO.


A measurement of anti-p p ---> pi+ pi- and anti-p p ---> k- k+ for small values of t and u at 3 and 4 gev/c

Brabson, A. ; Calvelli, G. ; Cittolin, S. ; et al.
Phys.Lett.B 42 (1972) 287-290, 1972.
Inspire Record 85008 DOI 10.17182/hepdata.28189

We have measured with good statistics the differential cross section for p p →π + π − , K + K − around 0°. Our data and previous results show that the s -dependence of dσ/d t has a value compatible with the appropriate baryon exchange.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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anti-p p Interactions at 2.32-GeV/c

Chen, C.K. ; Fields, T. ; Rhines, D.S. ; et al.
Phys.Rev.D 17 (1978) 42, 1978.
Inspire Record 5667 DOI 10.17182/hepdata.24405

A bubble-chamber experiment based on 304 000 events of p¯p interactions at 2.32 GeV/c is described. The film was automatically scanned and measured by the POLLY II system. Details of the data-analysis methods are given. We report results on cross sections for constrained final states, tests of C invariance, and inclusive pion and ρ0 multiplicity parameters for annihilation final states.

2 data tables
Table 1

Axis error includes +- 4/4 contribution.

Table 2

Axis error includes +- 4/4 contribution.


Anti-p p annihilation into pi+ pi- and k+ k- at 5 gev/c

Chabaud, V. ; Eide, A. ; Lehmann, P. ; et al.
Phys.Lett.B 41 (1972) 209-212, 1972.
Inspire Record 75628 DOI 10.17182/hepdata.5626

The differential cross-sections for the annihilation processes p p→π − π + and p p→K − K + have been measured at an incident laboratory momentum at 5 GeV/ c . Strong backward and forward peaks are observed in the π + π − differential cross-sections while the K + K − cross-section is shown to have a peak only for K − going forward. The annihilation cross-sections are compared with the cross-sections for the crossed channel backward processes π ± p→p π ± and K ± p→pK ± .

2 data tables
Table 1

No description provided.

Table 2

No description provided.