Crystal Ball
Electron production
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Measurement of K- p --> eta Lambda near threshold

The Crystal Ball collaboration Starostin, A. ; Nefkens, B.M.K. ; Berger, E. ; et al.
Phys.Rev.C 64 (2001) 055205, 2001.
Inspire Record 569202 DOI 10.17182/hepdata.25269

We present measurements of the differential and total cross sections and the Λ polarization for the reaction K−p→ηΛ from threshold to pK−=770MeV/c, with much better precision than previous measurements. Our cross-section data show a remarkable similarity to the SU(3) flavor-related π−p→ηn cross-section results. The reaction K−p→ηΛ at threshold is dominated by formation of the intermediate Λ(1670)12− state.

5 data tables
Table 1

Total cross section measurement for K- P --> ETA LAMBDA. Errors shown are statistical only.

Table 2

Differential cross sections DSIG/DOMEGA for K- P --> ETA LAMBDA. Errors shown are statistical only.

Table 3

Differential cross sections DSIG/DOMEGA for K- P --> ETA LAMBDA. Errors shown are statistical only.

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rivet Analysis
Measurement of pi0 and eta meson production in e+ e- annihilation at s**(1/2) near 10-GeV

The Crystal Ball collaboration Bieler, Ch. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 49 (1991) 225-234, 1991.
Inspire Record 297905 DOI 10.17182/hepdata.15082

We present a study of inclusive π0 and ŋ production ine+e− annihilation at

6 data tables
Table 1

Particle multiplicities in the continuum.

Table 2

Particle multiplicities in the UPSILON (1S).

Table 3

Inclusive pi0 spectra in the continuum.

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rivet Analysis
The Electron Spectrum From $B$ Meson Decays

The Crystal Ball collaboration Wachs, K. ; Antreasyan, D. ; Bartels, H.W. ; et al.
Z.Phys.C 42 (1989) 33, 1989.
Inspire Record 263581 DOI 10.17182/hepdata.45204

The Crystal Ball Collaboration has measured the energy spectrum of electrons from semileptonicB meson decays at thee+e− storage ring DORIS II. Branching ratios and weak mixing angles of the Kobayashi-Maskawa matrix are determined using several models for the hadronic matrix elements. We obtain the branching ratio for semileptonic.B decays to charmed states BR(B→evXc)=(11.7±0.4±1.0)%. Our result for the corresponding Kobayashi-Maskawa matrix element is |Vcb|=0.052±0.006. The model dependence of both results is included in the error. We have not observed semileptonicB decays to non-charmed mesons. Analyzing the measured electron spectrum above 2.4 GeV, where nob→c decays contribute, we find BR(B→evXu)/BR(B→evXc)<6.5% at the 90% confidence level. This corresponds to an upper limit |Vub/Vcb|<0.21.

1 data table
Table 1

The errors quoted are statistical only.


Formation of Delta (980) and A2 (1320) in Photon-photon Collisions

The Crystal Ball collaboration Antreasyan, D. ; Aschman, D. ; Besset, D. ; et al.
Phys.Rev.D 33 (1986) 1847, 1986.
Inspire Record 217547 DOI 10.17182/hepdata.23518

The reaction γγ→π0η has been investigated with the Crystal Ball detector at the DESY storage ring DORIS II. Formation of δ(980) and A2(1320) has been observed with γγ partial widths Γγγ(A2)=1.14±0.20±0.2 6 keV and Γγγ(δ)B(δ→πη)=0.19±0.07 −0.07+0.10 keV.

2 data tables
Table 1

No description provided.

Table 2

No description provided.