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Antiproton- 3 He annihilation events at rest have been detected using a self-shunted streamer chamber. The ratio of the cross section for annihilation on neutrons and on protons has been measured (0.467 ± 0.035). It is compared with other results from annihilation on free nucleons, deuterium, 3 He and 4 He. The low value of the ratio seems to indicate a strong isospin dependence of the antinucleon-nucleon P-wave amplitude.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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RESULTS ON LAMBDA(c)+, D(s)+, D0 AND D+ PRODUCTION PROPERTIES IN 230-GeV/c pi- Cu INTERACTIONS FROM THE NA32 EXPERIMENT

The ACCMOR collaboration Barlag, S. ; Becker, H. ; Bohringer, T. ; et al.

CERN-EP/88-104, 1988.

Inspire Record 264995 DOI 10.17182/hepdata.12879

None

33 data tables

Table 1

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 2

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 3

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

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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.

Anti-proton Proton Annihilation at Rest Into $\pi^0$ M and $\gamma$ M With M = $\phi$, $\eta^\prime$, $\omega$, $\rho^0$, $\eta$, and $\pi^0$

The Fukui-KEK-Kyoto Sangyo-Osaka-Tokyo Metropolitan collaboration Chiba, M. ; Fujitani, T. ; Iwahori, J. ; et al.

Phys.Rev.D 38 (1988) 2021, 1988.

Inspire Record 263258 DOI 10.17182/hepdata.23277

We have carried out high-statistics measurements of inclusive π0 and γ-ray spectra from p¯p annihilation at rest. From the monochromatic peaks in the π0 spectra, we derive the yield (or its upper limit) of the reaction p¯p→π0M for M=φ, η’, ω, ρ0, η, and π0. The same quantity was independently obtained from the γ-ray spectra, which included some π0’s that were mistaken as single γ rays due to the limited granularity of the γ detector. Taking the monochromatic peaks in the γ-ray spectra as being due to prompt γ rays, we also derive the upper limit for p¯p→γM.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Charge Symmetry Breaking in $n p$ Elastic Scattering at 477-{MeV}

Abegg, R. ; Bandyopadhyay, D. ; Birchall, J. ; et al.

Phys.Rev.D 39 (1989) 2464, 1989.

Inspire Record 267187 DOI 10.17182/hepdata.23224

The effect of isospin-violating, charge-symmetry-breaking (CSB) terms in the np interaction has been observed at TRIUMF by measuring the difference in the zero-crossing angles of the neutron and proton analyzing powers, An and Ap, at a neutron energy of 477 MeV. The scattering asymmetries were measured with a neutron beam incident on a polarizable proton target. To reduce systematic errors, interleaved measurements of An and Ap were made using the same beam and target (apart from their respective polarization states). Neutrons and protons were detected in coincidence in the center-of-mass angle range from 59°–80°. The difference in zero-crossing angles was 0.340°±0.162° (±0.058°), which yields ΔA≡An-Ap=0.0047±0.0022 (±0.0008) using dA/dθc.m.=−0.01382 deg−1. The second errors represent systematic effects. This result is in good agreement with recent theoretical calculations which include CSB effects due to the np mass difference in π, ρ, and 2π exchange, electromagnetic coupling of the neutron anomalous magnetic moment to the proton current, ρ-ω-meson mixing, and short- and medium-range effects of the up- and down-quark mass difference.

1 data table

Table 1

No description provided.

Evidence for Iota (1460) Production in $\pi^- p$ Interactions at 21.4-{GeV}/$c$

Rath, M.G. ; Cason, N.M. ; Bensinger, J.R. ; et al.

Phys.Rev.Lett. 61 (1988) 802, 1988.

Inspire Record 262921 DOI 10.17182/hepdata.20086

The KS0KS0π0 system has been studied in the exclusive reaction π−p→KS0KS0π0n at 21.4 GeV/c. Evidence for the production of the f1(1285) and the η(1460) is presented. The η(1460) is produced away from minimum momentum transfer in the presence of nonresonant K*K (S-wave) production and phase-space background. The observed mass, width, and decay properties of the η(1460) are consistent with those attributed to the ι(1460) observed in radiative Jψ decay.

1 data table

Table 1

No description provided.

Differential Cross-sections and Analyzing Powers for Small Angles $N P$ Elastic Scattering Between 376-{MeV} and 1135-{MeV}

Silverman, B.H. ; Lugol, J.C. ; Saudinos, J. ; et al.

Nucl.Phys.A 499 (1989) 763-788, 1989.

Inspire Record 264337 DOI 10.17182/hepdata.36902

We have measured absolute differential cross sections and analyzing powers for neutron-proton elastic scattering for momentum transfer 0.01 < | t |< 0.08 (GeV/ c ) 2 at several energies between 378 and 1135 MeV. The ionization chamber IKAR filled with methane was used as both a gas target and recoil detector. For the analyzing-power measurements the scattered neutron was detected in scintillation counters in coincidence with the recoil proton detected in IKAR. Special care was taken to ensure a precise absolute normalization of the cross sections, with overall systematic uncertainties of 4–7%.

19 data tables

Table 1

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=6.4 PCT.

Table 2

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=5.4 PCT.

Table 3

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=6.5 PCT.

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

Balestra, F. ; Bossolasco, S. ; Bussa, M.P. ; et al.

Phys.Lett.B 215 (1988) 247-250, 1988.

Inspire Record 264048 DOI 10.17182/hepdata.29876

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.

2 data tables

Table 1

Charged prong multiplicity distribution in annihilation events.

Table 2

Measured inelastic cross section.

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TOTAL DISINTEGRATION OF HELIUM NUCLEI IN He-3 p INTERACTIONS AT 13.5-GeV/c

THE STUDY OF NEUTRON INTERACTIONS WITH PROTONS AND CARBON NUCLEI AT p = 4.2-GeV/c

Evidence of Isospin Effects in Anti-proton - Nucleus Annihilation

RESULTS ON LAMBDA(c)+, D(s)+, D0 AND D+ PRODUCTION PROPERTIES IN 230-GeV/c pi- Cu INTERACTIONS FROM THE NA32 EXPERIMENT

rivet Analysis
The Electron Spectrum From $B$ Meson Decays

Anti-proton Proton Annihilation at Rest Into $\pi^0$ M and $\gamma$ M With M = $\phi$, $\eta^\prime$, $\omega$, $\rho^0$, $\eta$, and $\pi^0$

Charge Symmetry Breaking in $n p$ Elastic Scattering at 477-{MeV}

Evidence for Iota (1460) Production in $\pi^- p$ Interactions at 21.4-{GeV}/$c$

Differential Cross-sections and Analyzing Powers for Small Angles $N P$ Elastic Scattering Between 376-{MeV} and 1135-{MeV}

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