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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.

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Azimuthal Correlations of ($\pi^+ \pi^-$) Pairs in Pion - Nucleus and Pion - Nucleon Interactions at $p$ = 40-{GeV}/$c$

Grishin, V.G. ; Jenik, L. ; Kanarek, T. ;

JINR-P1-80-348, 1980.

Inspire Record 154325 DOI 10.17182/hepdata.17811

None

9 data tables

Table 1

No description provided.

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Measurement of Dimuon Production at the {ISR}

Antreasyan, D. ; Atwood, W. ; Battiston, R. ; et al.

Phys.Rev.Lett. 45 (1980) 863, 1980.

Inspire Record 153857 DOI 10.17182/hepdata.20656

Prompt dimuon production has been measured. Events with mass up to 25 GeV/c2 are observed, as well as the J and ϒ resonances. Cross sections are given for J and ϒ production. For the continuum, the scaling function F(τ) is measured at very small values of τ=ms covering the range 0.05<τ<0.20.

3 data tables

Table 1

No description provided.

Table 2

HERE UPSILON = ALL USILON FAMILY. ANGULAR DISTBN. IS SEEN TO BE ISOTROPIC.

Table 3

No description provided.

ANGULAR DEPENDENCE OF HIGH P(T) pi0 PRODUCTION

Lloyd Owen, D. ; Abshire, G.W. ; Finocchiaro, G. ; et al.

Phys.Rev.Lett. 45 (1980) 89, 1980.

Inspire Record 153201 DOI 10.17182/hepdata.20655

The π0 inclusive cross section for c.m. production angles θ=90° and 22°>~θ>~5° at c.m. energies of s=23 and 53 GeV has been measured. This cross section is strongly dependent on both θ and s at small angles. The hypothesis of radial scaling is shown to be incapable of incorporating both θ and s dependence of the cross section. A recent quantum-chromodynamics calculation is in qualitative agreement with our results.

14 data tables

Table 1

No description provided.

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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.

Transverse Momentum of Hadrons Produced in Neutrino and Anti-neutrino Interactions on an Isoscalar Target in BEBC

The Aachen-Bonn-CERN-Democritos-London-Oxford-Saclay collaboration Deden, H. ; Fritze, P. ; Grassler, H. ; et al.

Nucl.Phys.B 181 (1981) 375, 1981.

Inspire Record 153272 DOI 10.17182/hepdata.34301

The average transverse momentum squared, 〈 p ⊥ 2 〉, of hadrons is studied as a function of W 2 and of Q 2 for ν and ν interactions on an isoscalar target. An increase of 〈 p ⊥ 2 〉 with W 2 is observed for the hadrons emitted forward in the hadronic c.m.s. The p ⊥ dependence of the fragmentation function is found to factorise from the structure function at fixed W , but does not factorise at fixed Q 2 . Unlike the case of forward-going particles, the 〈 p ⊥ 2 〉 of hadrons going backward in the c.m.s. shows no strong dependence on W 2 .

4 data tables

Table 1

No description provided.

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$K^\pm p$ Large Angle Elastic Scattering at 20-{GeV}/$c$ and 30-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Almas, R. ; Baglin, C. ; Bock, R. ; et al.

CERN-EP/80-79, 1980.

Inspire Record 153574 DOI 10.17182/hepdata.49655

None

3 data tables

Table 1

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Measurement of the Reaction $e^+ e^- \to \gamma \gamma$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.

Phys.Lett.B 94 (1980) 87-90, 1980.

Inspire Record 153120 DOI 10.17182/hepdata.27174

The differential cross section for the reaction e + e − → γγ has been measured in the CMS energy range between 9.4 and 31.6 GeV. The results are found to be in agreement with the predictions of quantum electrodynamics up to momentum transfers- q 2 of 900 GeV 2 . The data set lower limits of about 40 GeV on QED cut-off parameters. We have searched for the decay υ (9.46) → γγ and obtain an upper limit Γ ( υ → γγ )/ Γ ( υ → all) < 1.4% (95% c.l.).

1 data table

Table 1

No description provided.

Backward $\pi d$ Scattering Between 140-{MeV} and 260-{MeV}

The OMICRON collaboration Stanovnik, A. ; Kernel, G. ; Tanner, N.W. ; et al.

Phys.Lett.B 94 (1980) 323-326, 1980.

Inspire Record 153157 DOI 10.17182/hepdata.27191

Differential cross sections for elastic scattering of pions by deuterons have been measured for centre-of-mass angles between 130° and 175°, and at laboratory energies 141, 177, and 260 MeV for π + , and at 151, 185, and 189 MeV for π − . At 177 and 260 MeV the cross sections are a factor of 2 lower than the predictions of three-body theories.

6 data tables

Table 1

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