HEPData Search

Some experimental properties of the charged hadronic fragments are compared for νp, νn,$\bar vp$ and$\bar vn$ interactions: multiplicities of forward and backward going particles,xF distributions for pions, fragmentation functions and theirQ2 andW2 dependence. The results are compared with the predictions of the Lund fragmentation model.

1 data table

Table 1

No description provided.

Production of the F(0) Meson in Photon-photon Collisions

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.

Z.Phys.C 23 (1984) 223, 1984.

Inspire Record 199731 DOI 10.17182/hepdata.16320

The production of thef0 in two photon collisions, with the subsequent decayf0→π+π− has been observed in the CELLO detector at PETRA. Thef0 peak was found to lie on a dipion continuum and to be shifted downwards in mass by ≃50 MeV/c2. The ππ mass spectrum from 0.8 to 1.5 GeV/c2 was well fitted by the model of Mennessier using only a unitarised Born amplitude and helicity 2f0 amplitude. The previously observed mass shift and distortion of thef0 peak are explained by strong interference between the Born andf0 amplitudes. The only free parameter in the fit of the data to the model is the radiative widthΓγγ(f0). It was found that:Γγγ(f0)=2.5±0.1±0.5 keV where the first (second) quoted errors are statistical (systematic).

2 data tables

Table 1

Data read from graph.

Table 2

Data read from graph.

Experimental Test of the Flavor Independence of the Quark - Gluon Coupling Constant

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.

Phys.Lett.B 138 (1984) 317-324, 1984.

Inspire Record 199470 DOI 10.17182/hepdata.6609

Reconstruction of charged D ∗ 's produced inclusively in e + e −. annihilation at CM energies near 34.4 GeV is accomplished in the decay modes D ∗ + → D 0 π + → K − gp + π 0 π + and D ∗ + → D 0 π + → K − gp + π − π + π + and their charge conjugates. Using these and previously reported D ∗ + → D 0 π + → K − gp + π + and D ∗ + → D 0 π + → K − gp + π + + missing π 0 channels we present evidence for hard gluon bremsstrahlung from charm quarks and show that the ratio of the quark-gluon coupling constant of charm quarks to the coupling constant obtained in the average hadronic event, α s c α rms = 100 ± 0.20 ± 1.20 . Our result provides evidence that the quark-gluon coupling constant is independent of flavor.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

ANTI-NEUTRINOS QUASIELASTIC SCATTERING IN NEON AND TOTAL CROSS-SECTIONS IN THE ENERGY INTERVAL 10-GEV - 50-GEV

Asratian, A.E. ; Gorichev, P.A. ; Efremenko, V.I. ; et al.

Yad.Fiz. 39 (1984) 619-625, 1984.

Inspire Record 206651 DOI 10.17182/hepdata.10181

None

2 data tables

Table 1

No description provided.

Table 2

No description provided.

NEUTRAL STRANGE PARTICLE PRODUCTION IN ANTI-NEUTRINOS INDUCED NEUTRAL CURRENT INTERACTIONS

Asratian, A.E. ; Efremenko, V.I. ; Fedotov, A.V. ; et al.

Phys.Lett.B 140 (1984) 127-129, 1984.

Inspire Record 200832 DOI 10.17182/hepdata.10145

The study of neutral strange particle production in antineutrino-induced neutral current interactions is presented. The total multiplicity of neutral strange particles and the K 0 multiplicity in the current fragmentation region ( z >0.3) are used to estimate in two ways the coupling strength of the weak neutral current to the strange quark.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Tests of QED at 29-GeV Center-Of-Mass Energy

Bender, D. ; Derrick, M. ; Fernandez, E. ; et al.

Phys.Rev.D 30 (1984) 515, 1984.

Inspire Record 199464 DOI 10.17182/hepdata.23593

During the initial data run with the High Resolution Spectrometer (HRS) at SLAC PEP, an integrated luminosity of 19.6 pb−1 at a center-of-mass energy of 29 GeV was accumulated. The data on Bhabha scattering and muon pair production are compared with the predictions of QED and the standard model of electroweak interactions. The measured forward-backward charge asymmetry in the angular distribution of muon pairs is -8.4%±4.3%. A comparison between the data and theoretical predictions places limits on alternative descriptions of leptons and their interactions. The existence of heavy electronlike or photonlike objects that alter the structure of the QED vertices or modify the propagator are studied in terms of the QED cutoff parameters. The Bhabha-scattering results give a lower limit on a massive photon and upper limits on the effective size of the electron of Λ+>121 GeV and Λ−>118 GeV at the 95% confidence level. Muon pair production yields Λ+>172 GeV and Λ−>172 GeV. If electrons have substructure, the magnitude and character of the couplings of the leptonic constituents affects the Bhabha-scattering angular distributions to such an extent that limits on the order of a TeV can be extracted on the effective interaction length of the components. For models in which the constituents interact with vector couplings of strength g24π∼1, the energy scale ΛVV for the contact interaction is measured to be greater than 1419.0 GeV at the 95% confidence level. We set limits on the production of supersymmetric scalar electrons through s-channel single-photon annihilation and t-channel inelastic scattering. Using events with two noncollinear electrons and no other charged or observed neutral particles in the final state, we see one event which is consistent with a simple supersymmetric model but which is also consistent with QED. This allows us to exclude the scalar electron to 95% confidence level in the mass range 1.8 to 14.2 GeV/c2.

3 data tables

Table 1

Comparison of Bhabhas with QED.

Table 2

Muon angular distributions.

Table 3

Forward-backward asymmetry from full angular range.

Charm Quark Production and Fragmentation in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Lett.B 146 (1984) 261-265, 1984.

Inspire Record 202898 DOI 10.17182/hepdata.51261

The electroweak production asymmetry and the decay fragmentation function for e + e − → c c have been measured at s = 29 GeV using charged D ∗ production over the full kinematic range. The data were taken at PEP using the High Resolution Spectrometer. The measured asymmetry is −0.12 ± 0.08. The total production cross section in units of the point cross section corrected for initial state radiation is R D ∗ = 2.7 ± 0.9 .

2 data tables

Table 1

ASSUMES SIG(D*+) = SIG(D*0). (EXPT. MEASURES D*+ PRODUCTION ONLY). R VALUE CORRECTED FOR INITIAL STATE RADIATION.

Table 2

No description provided.

rivet Analysis
Inclusive D0 and $D^+$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Rev.Lett. 53 (1984) 1971, 1984.

Inspire Record 202899 DOI 10.17182/hepdata.51258

We have observed inclusive production of D0 and D+ mesons, and their charge conjugates, in e+e− annihilation at 29 GeV on the basis of a data sample of 106 pb−1. These signals correspond to R values of R(D0+D―0)=1.8±0.5 and R(D++D−)=1.2±0.4. Taking the D+ and D0 data together, we measure a charge asymmetry of A=−0.08±0.12 for charmed quarks. A comparison of R(D+D―) with R(D*+D―*) obtained via the process D*+→D0π+ gives a DD* ratio of 1.0−0.2+0.3, indicating that direct D* production dominates over direct D production.

4 data tables

Table 1

No description provided.

Table 2

EXTRAPOLATED TO ALL Z.

Table 3

No description provided.

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