HEPData Search

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rivet Analysis
Total Cross-section for Hadron Production by $e^+ e^-$ Annihilation Between 9.4-{GeV} and 9.5-{GeV}

The DESY-Hamburg-Heidelberg-Munich collaboration Bock, P. ; Heinzelmann, G. ; Pietrzyk, B. ; et al.

Z.Phys.C 6 (1980) 125, 1980.

Inspire Record 153896 DOI 10.17182/hepdata.14364

The total cross section fore+e− annihilation into hadrons for center of mass energies from 9.4 to 9.5 GeV has been measured with the nonmagnetic DESY-Heidelberg detector at DORIS. A value ofR=σhad/σµµ=3.8±0.7 for the continuum region around the Υ (9.46) resonance has been determined. The ratioΓeeΓhad/Γtot of electronic, hadronic and total widths has been reevaluated to be (1.00±0.23) keV for the Υ resonance and (0.37±0.16) keV for the Υ′. In addition, a search for directly produced pohotons from Υ decays of the type Υ→γ+gluon+gluon has been performed. The Υ decay into muon pairs has also been searched for.

1 data table

Table 1

TOTAL CROSS SECTION FOR THE CONTINUUM REGIONS AROUND THE UPSI(9460)0 AND UPSI(10020)0 RESONANCES.

Study of the Reactions $\pi^- p \to K^0 \Lambda$ and $\pi^- p \to K^0 \Sigma^0$ at 3.95-{GeV}/$c$

The CERN-College de France-Madrid-Stockholm collaboration Loverre, P.F. ; Armenteros, R. ; Dionisi, C. ; et al.

Z.Phys.C 6 (1980) 283, 1980.

Inspire Record 153918 DOI 10.17182/hepdata.14374

The reactions π−p→K0Λ,K0Σ0 are studied at an incident momentum of 3.95 GeV/c using data from a high statistics bubble chamber experiment corresponding to ∼90 events/μb. The differential cross sections and hyperon polarizations are presented and compared with existing data from earlier electronic experiments. The data in the forward hemisphere are used to perform an amplitude analysis of the 0−1/2+→0−1/2+ hypercharge exchange processes.

9 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Study of the Reactions $\pi^- p \to K^0 \Sigma^0(1385)$ and $\pi^- p \to K^+ \Sigma^-(1385)$ at 3.95-{GeV}/$c$

The CERN-College de France-Madrid-Stockholm collaboration Aguilar-Benitez, M. ; Albajar, M.C. ; Ferrando, A. ; et al.

Z.Phys.C 6 (1980) 109-123, 1980.

Inspire Record 153921 DOI 10.17182/hepdata.14369

The reactionsπ−p→K0∑0(1385) andπ−p→K+∑−(1385) are studied at an incident momentum of 3.95 GeV/c using data from a high statistics bubble chamber experiment corresponding to approximately 90 events/μb. The total and differential cross sections and the density matrix elements of the Σ(1385) are presented. The results are compared with those obtained for the related processesπpp→K+∑+(1385) and$K^ -p \to \pi ^ \mp\sum ^ \pm(1385)$ in this energy range. Evidence is presented for the existence of production mechanisms with exotic exchanges in thet channel.

16 data tables

Table 1

FROM THE CHANNEL PI- P --> LAMBDA K0 PI0 WHICH HAS A CROSS SECTION OF 72 +- 4 MUB.

Table 2

FROM THE CHANNEL PI- P --> LAMBDA K+ PI- WHICH HAS A CROSS SECTION OF 79 +- 3 MUB.

Table 3

FORWARD CROSS SECTION.

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Total Width and Leptonic Branching Ratio of the $\Upsilon$ (9.46)

The LENA collaboration Niczyporuk, B. ; Zeludziewicz, T. ; Chen, K.W. ; et al.

Phys.Rev.Lett. 46 (1981) 92, 1981.

Inspire Record 153813 DOI 10.17182/hepdata.20644

With use of the LENA detector at the DORIS e+e− storage ring, the hadronic cross section and the μ-pair decay branching ratio of the ϒ(9.46) resonance have been measured. Γee=1.23±0.10 (±0.14) keV, Bμμ=[3.5±1.4 (±0.4)]%, and Γtot=35−10+25 ({+9}{−7}) keV have been obtained. The first set of errors gives the statistical uncertainty. The numbers in parentheses represent systematic errors arising from the uncertainty in the total hadronic cross section.

1 data table

Table 1

No description provided.

Observation of the Upsilon''' at CESR

Finocchiaro, G. ; Giannini, G. ; Lee-Franzini, Juliet ; et al.

Phys.Rev.Lett. 45 (1980) 222, 1980.

Inspire Record 9427 DOI 10.17182/hepdata.20691

During an energy scan at the Cornell Electron Storage Ring, with use of the Columbia University-Stony Brook NaI detector, an enhancement in σ(e+e−→hadrons) is observed at center-of-mass energy ∼10.55 GeV. The mass and leptonic width of this state (ϒ′′′) suggest that it is the 4S13 bound state of the b quark and its antiquark. After applying to the data a cut in a (pseudo) thrust variable, the natural width is measured to be Γ=12.6±6.0 MeV, indicating that the ϒ′′′ is above the threshold for BB¯ production.

1 data table

Table 1

VISIBLE TOTAL HADRONIC CROSS SECTION FOR FIRST, THIRD AND FOURTH UPSILONS.

Measurements of the Properties of d Meson Decays

Schindler, R.H. ; Alam, M.S. ; Boyarski, A. ; et al.

Phys.Rev.D 24 (1981) 78, 1981.

Inspire Record 156644 DOI 10.17182/hepdata.24006

We present a study of the decay properties of charmed D mesons produced near the peak of the ψ′′(3770) resonance in e+e− annihilation. Branching fractions for nine Cabibbo-favored and three Cabibbo-suppressed decay modes are presented along with upper limits on one additional Cabibbo-favored and four additional Cabibbo-suppressed decay modes. A study of Kππ-decay-mode Dalitz plots reveals a large quasi-two-body pseudoscalar-vector component for the D0 decays and an apparent nonuniform population on the Dalitz plot for the D+ decay into K−π+π+. Using tagged events, we measure the charged-particle multiplicity and strange-particle content of D decays. A measurement of the D+ and D0 semileptonic decay fractions indicates that the D+ has a significantly longer lifetime than the D0.

1 data table

Table 1

INCLUSIVE CROSS SECTIONS UNCORRECTED FOR RADIATIVE EFFECTS.

Xi (1320) and Xi (1530) Production in $K^- p$ Interactions at 4.2-{GeV}/$c$

The Amsterdam-CERN-Nijmegen-Oxford collaboration Mazzucato, M. ; Pennino, D. ; Aguilar-Benitez, M. ; et al.

Nucl.Phys.B 178 (1981) 1-30, 1981.

Inspire Record 153470 DOI 10.17182/hepdata.34384

The reactions K − p → Ξ 0 − (1320) K 0 + , Ξ − (1320) K + (890), Ξ 0 − (1530) K 0 − and Ξ 0 − (1530) K 0 + (890) are studied at 4.2 GeV/ c incident momentum. The data come from a high-statistics bubble chamber experiment with a sensitivity of ∼ 133 events/ μ b. Total anddifferential cross sections are presented. The results are compared to the SU(3)-related processes K + p → pK + and K + p → pK + (890) in the backward hemisphere. In the forward hemisphere “forbidden” peaks are observed and current ideas about them are discussed.

16 data tables

Table 1

FULLY CORRECTED FOR ALL CUTS AND UNSEEN DECAY MODES.

Table 2

TOTAL, FORWARD AND BACKWARD CROSS SECTIONS. FULLY CORRECTED FOR CUTS, K0 AND LAMBDA UNSEEN DECAY MODES AND OTHER K*(892) AND XI(1530P13) DECAYS. IN 3-BODY FINAL STATES, THETA REFERS TO THE PI-K SYSTEM.

Table 3

No description provided.

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Inclusive Production of Strangeness $S = \pm 1$ Vector and Tensor Resonances on $K^- P$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Arestov, Yu. ; Borovikov, A. ; Kozlovsky, E. ; et al.

Z.Phys.C 6 (1980) 101-108, 1980.

Inspire Record 154719 DOI 10.17182/hepdata.11053

We present final results on the inclusive production of the$\bar K^{*0} (890)$,K*−(890),K*0(890),K*−(890),K*−(1420), and$\bar K^{*0} (1420)$ resonances inK−p interactions at 32 GeV/c. Total cross sections and invariantx-distributions are determined. Inclusive cross sections of$\bar K^{*\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{o} } (890)$ amount to ≃4 mb each, of$\bar K^{*\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{o} } (1420)$ to ≃1 mb and ofK*0(890) to ≃0.8 mb. These values are in agreement with additive quark model predictions. All strangenessS=−1 resonances are predominantly produced in the forward hemisphere, the tensor mesons being more peripherally produced than the vector ones. The$\bar K^{*\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{o} } (890)$ density matrix elements andt-distributions are obtained. The unnatural spin-parity exchange contribution to inclusive$\bar K^{*\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{o} } (890)$ production amounts to ≳60% at |t|<0.4 GeV2 and decreases with increasing |t|. Whenever relevant, a comparison is also made with available data at other energies.

11 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Comparison of e+ e- Annihilation with QCD and Determination of the Strong Coupling Constant

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.

Phys.Lett.B 94 (1980) 437-443, 1980.

Inspire Record 153511 DOI 10.17182/hepdata.5489

We have analyzed 1113 events of the reaction e + e − → hadrons at CM energies of 12 and 30 GeV in order to make a detailed comparison with QCD. Perturbative effects can be well separated from effects depending on the quark and gluon fragmentation parameters to yield a reliable measurement of the coupling constant α S . At 30 GeV, the result is α S = 0.17 ± 0.02 (statistical) ± 0.03 (systematic). QCD model predictions, using the fragmentation parameters determined along with α S , agree with both gross properties of the final states and with detailed features of the three-jet states.

7 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.