Measurement of gamma p --> K+ Lambda and gamma p --> K+ Sigma0 at photon energies up to 2-GeV .

The SAPHIR collaboration Tran, M.Q. ; Barth, J. ; Bennhold, C. ; et al.
Phys.Lett.B 445 (1998) 20-26, 1998.
Inspire Record 483236 DOI 10.17182/hepdata.27074

Associated strangeness production in the reactions γp → K + Λ and γp → K + Σ 0 was measured with the SAPHIR detector at the electron stretcher ring ELSA at Bonn. Data on total and differential cross sections and on hyperon polarizations are presented. The total cross section for Λ production shows a strong threshold enhancement whereas the Σ 0 data have a maximum at about E γ =1.45 GeV. Along with the angular decomposition of the differential cross section into polynomials, this suggests resonance production. However, the angular distributions of both hyperon polarizations vary only slightly with the photon energy. Λ and Σ 0 polarizations show opposite signs and change sign over the angular range.

10 data tables

Total cross section for the reaction GAMMA P --> K+ LAMBDA.

Total cross section for the reaction GAMMA P --> K+ SIGMA0.

Differential cross section for the reaction GAMMA P --> K+ LAMBDA in the GAMMA energy range 0.90 to 1.10 GeV in three energy bins.

More…

Measurement of gamma p ---> K+ Lambda and gamma p ---> K+ Sigma0 at photon energies up to 1.47-GeV

Bockhorst, M. ; Burbach, G. ; Burgwinkel, R. ; et al.
Z.Phys.C 63 (1994) 37-47, 1994.
Inspire Record 380478 DOI 10.17182/hepdata.14114

The reactions γp→K+ Λ and γp→K+ Σ0 have been measured with the multiparticle detector system SAPHIR at ELSA in Bonn. Besides the differential cross sections the Λ polarization and, for the first time, the Σ0 polarization have been determined in a photon induced reaction. All data are presented as functions of the photon energy (from threshold up to 1.47 GeV) and of the kaon production angle (0°–180°). The polarization of both Λ and Σ0 is substantial at all energies and varies strongly with the production angle.

8 data tables

Differential cross sections.

Total cross sections.

Differential cross sections.

More…

Photoproduction of k+ lambda0 and k+ sigma0 from hydrogen at constant momentum transfer t between 1.05 and 2.2 gev

Feller, P. ; Menze, D. ; Opara, U. ; et al.
Nucl.Phys.B 39 (1972) 413-420, 1972.
Inspire Record 75243 DOI 10.17182/hepdata.32925

For the reaction γ p → K + Λ 0 the differential cross section has been measured at t = −0.147 GeV 2 ( θ C.M. = 26.5 ± 3.5°) and photoenergies between 1.05 and 2.2 GeV and for the reaction γ p→K + Σ 0 at ≈−0.17 GeV 2 ( θ C.M. = 28±3.5°) and photoenergies between 1.3 and 2.2 GeV. For this four momentum transfer the differential cross section of K + Λ 0 photoproduction has a surprising steep increase above threshold and stays nearly constant up to 2.2 GeV. The K + Σ 0 cross section increases from 1.3 to 1.56 GeV and goes down gradually at higher energies.

2 data tables

AT CONSTANT MOMENTUM TRANSFER OF -T = 0.147 GEV**2.

AT APPROXIMATELY CONSTANT MOMENTUM TRANSFER OF -T = 0.17 GEV**2.