HEPData Search

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rivet Analysis
Transverse Momentum Distributions of Charged Particles Produced in anti-p p Interactions at s**(1/2) = 630-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.

Phys.Rev.Lett. 61 (1988) 1819, 1988.

Inspire Record 263320 DOI 10.17182/hepdata.20105

Measurements of inclusive transverse-momentum spectra for charged particles produced in proton-antiproton collisions at √2 of 630 and 1800 GeV are presented and compared with data taken at lower energies.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Results of fit to invariant cross section of the form AP0**N/(PT + P0)**N.

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Evidence of Isospin Effects in Anti-proton - Nucleus Annihilation

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

Nucl.Phys.A 491 (1989) 572-586, 1989.

Inspire Record 264049 DOI 10.17182/hepdata.37013

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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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.

Analyzing Power Measurement in Inclusive $\pi^0$ Production at High $\chi_F$

Bonner, B.E. ; Buchanan, J.A. ; Carey, D.C. ; et al.

Phys.Rev.Lett. 61 (1988) 1918, 1988.

Inspire Record 269386 DOI 10.17182/hepdata.2928

The analyzing power AN in inclusive π0 production has been measured with use of the new 185-GeV/c Fermilab polarized proton beam. We obtain the value AN=0.10±0.03 for π0's in the kinematic region 0.2<xF<0.8 and 0.3<pT<1.2 GeV/c. In certain models of particle production this suggests that the spin of the proton is carried by its valence quarks.

7 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Individual polarisation measurements.

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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.

Experimental Investigation of the Energy Dependence of the Strong Coupling Strength

The JADE collaboration Bethke, S. ; Allison, John ; Ambrus, K. ; et al.

Phys.Lett.B 213 (1988) 235-241, 1988.

Inspire Record 263579 DOI 10.17182/hepdata.29894

The energy dependence of the relative production rate of three-jet events is studied in hadronic e + e − annihilation events at center of mass energies between 22 and 46.7 GeV. Three-jet events are defined by a jet finding algorithm which is closely related to the definition of resolvable jets used in O( α s 2 ) perturbative QCD calculations, where the relative production rate of three-jet events is roughly proportional to the size of the strong coupling strength. The production rates of three-jet events in the data decrease significantly with increasing centre of mass energy. The experimental rates, which are independent of fragmentation model calculations, can be directly compared to theoretically calculated jet production rates and are in good agreement with the QCD expectations of a running coupling strength. The hypothesis of an energy independent coupling constant can be excluded with a significance of four standard derivations.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of D, D* and D(s) Mesons in 200-GeV/c pi-, K- and p Si Interactions

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

Z.Phys.C 39 (1988) 451, 1988.

Inspire Record 263857 DOI 10.17182/hepdata.15617

The NA 32 experiment at the CERN SPS has collected 38 million hadronic interactions with incident 200 GeV/c π−,K− andp beam. Using a segmented silicon active target and a telescope of high resolution silicon microstrip counters we have selected fully reconstructedD0→K−π+,D0→K−π+π+π−,D+→K−π+π+,Ds+→K−K+π+π+ and charge conjugate decays. The integrated cross-sections forDo,D+D*+ andDs+ meson production and the dependence of the cross-section on longitudinal and transverse momentum of theD are presented.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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.

Precision Measurement of R = $\sigma^-$l / $\sigma^- T$ and F(2) in Deep Inelastic Electron Scattering

Dasu, S. ; De Barbaro, P. ; Bodek, A. ; et al.

Phys.Rev.Lett. 61 (1988) 1061, 1988.

Inspire Record 262063 DOI 10.17182/hepdata.20079

We report new results on a precision measurement of the ratio R=σLσT and the structure function F2 for deep-inelastic electron-nucleon scattering in the kinematic range 0.2≤x≤0.5 and 1≤Q2≤10 (GeV/c)2. Our results show, for the first time, a clear falloff of R with increasing Q2. Our R and F2 results are in good agreement with QCD predictions only when corrections for target-mass effects are included.

9 data tables

Table 1

2.6 pct rad length target.

Table 2

2.6 pct rad length target.

Table 3

2.6 pct rad length target.