Alvarez, R.
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An Analysis of the Charged and Neutral Energy Flow in $e^+ e^-$ Hadronic Annihilation at 34-{GeV}, and a Determination of the {QCD} Effective Coupling Constant

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 113 (1982) 427-432, 1982.
Inspire Record 177228 DOI 10.17182/hepdata.30921

Using both charged and neutral components, 2600 multihadronic e + e − annihilation events, recorded at 34 GeV by the CELLO detector at PETRA, have been analysed in a calometric approach. The fraction of energy carried by gamma rays is measured to be f γ = (26.0 ± 0.4 (stat) ± 4.0 (syst)%. The neutral energy flow is seen to follow closely the overall energy flow. From the corrected oblateness distribution, a first order determination of α s is performed. The result is α s = 0.16 ± 0.01 (stat) ± 0.03 (syst).

1 data table
Table 1

No description provided.


Measurement of Inclusive $\gamma$ and $\pi^0$ Spectra and a Comparison of the Neutral and Charged Components in Hadronic Events in $e^+ e^-$ Annihilation at 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 189, 1982.
Inspire Record 177212 DOI 10.17182/hepdata.16411

The photonic part of multihadronice+e− annihilation events has been analyzed at a c.m. energy of 34 GeV. The photonic energy fraction per event is determined to befγ=0.251±0.003 (stat.) ±0.04 (syste.). The neutral and charged components of the events are analyzed separately revealing close similarity in thrust axis directions and momentum distributions in agreement with the hypothesis that most photons result from π0 decay. π0's are reconstructed separately and used to determine the inclusive cross section. Comparing these cross sections with lower energy data from SPEAR we find some indication for scaling violation.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Observation of Semileptonic Decays of Charmed Baryons

Vella, E. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 48 (1982) 1515, 1982.
Inspire Record 176986 DOI 10.17182/hepdata.19674

Direct electrons are observed in baryon events produced in e+e− annihilation at center-of-mass energies above the ΛcΛ¯c threshold. These events are attributed to charmed-baryon pair production and subsequent Λc semileptonic decay. Various semileptonic branching ratios of the Λc are determined, including B(Λc→e+X)=(4.5±1.7)%.

2 data tables
Table 1

ELECTRON-BARYON RATIO ABOVE AND BELOW LAMBDA/C THRESHOLD.

Table 2

No description provided.


Measurement of the Reaction $e^+ e^- \to \mu^+ \mu^-$ for 14-{GeV} $\le \sqrt{s} \le$ 36.4-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J.H. ; et al.
Z.Phys.C 14 (1982) 283, 1982.
Inspire Record 177216 DOI 10.17182/hepdata.16414

The reaction (e+e−→μ+μ−) has been measured between\(\sqrt S= 14.0\) and\(\sqrt S= 36.4\). The total cross section result is in good agreement with the QED prediction and the following Λ values have been obtained:Λ+=186 GeV,Λ−=101 GeV. The angular distribution at high energy (\(\left( {\left. {\left\langle {\sqrt S } \right.} \right\rangle= 34.2 GeV} \right)\)) shows a fitted charge asymmetry of −0.064±0.064 in agreement with theW-S model prediction of −0.092, corresponding to an axial coupling parametera2=4ga2=0.69±0.69.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Errors include contribution from systematics. Result based on fit(1 + cos(theta)**2 + q cos(theta)) to corrected angular distribution.


Measurement of the Neutral Current to Charged Current Ratio for Anti-neutrinos Proton Inclusive Scattering

Carmony, D.D. ; Carman, T.S. ; Barnes, V.E. ; et al.
Phys.Rev.D 26 (1982) 2965, 1982.
Inspire Record 11799 DOI 10.17182/hepdata.23944

The Fermilab wide-band antineutrino beam incident on the hydrogen-filled 15-foot bubble chamber was used to study ν¯p neutral-current interactions. The u=x(1−y) distribution is presented for both the neutral- and the charged-current data sample. Fitting the neutral-current u distribution to the prediction of a simple quark-parton model measures the Weinberg angle. By using recent measurements of the neutral-to-charged-current cross-section ratio for νp interactions (Rp), we find the corresponding ratio for ν¯p interactions (R¯p) to be 0.36±0.06.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


A Study of Two Photon Production of Two-body Final States With Invariant Mass Greater Than 2.0-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Nucl.Phys.B 202 (1982) 189-200, 1982.
Inspire Record 176691 DOI 10.17182/hepdata.34157

We have measured the electron, muon, and charged-hadron pair production rates in two-phonon interactions for invariant masses above 2.0 GeV over a large of momentum transfer. The cross sections for electron and muon pairs show good agreement with the QED predictions at both small and large momentum transfer. The observed rate of hadron production is less than 6% of the rate that QED predicts for point-like hadrons, consistent with recent leading-order QCD calculations.

5 data tables
Table 1

LOW Q**2 CROSS SECTIONS.

Table 2

DIFFERENTIAL CROSS SECTIONS IN THE INVARIANT MASS FOR MUON AND ELECTRON PAIRS IN THE UNTAGGED, LOW Q**2 REGION.

Table 3

HIGH Q**2 CROSS SECTIONS.

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Measurement of Hadronic Production of the $\chi$ 1++ (3507) and the $\chi$ 2++ (3553) Through Their Radiative Decay to $J/\psi$

Lemoigne, Y. ; Barate, R. ; Bareyre, P. ; et al.
Phys.Lett.B 113 (1982) 509, 1982.
Inspire Record 176731 DOI 10.17182/hepdata.30918

The χ 1 ++ (3507) and the χ 2 ++ (3553) states have been observed in the Goliath spectrometer at the CERN SPS in 185 GeV/ c π − -Be collisions. Their radiative decays contribute 27.7% (for the χ 1 ++ ) and 12.8% (for the χ 2 ++ ) to J ϕ production. At this energy, their cross sections are 65±19 nb and 96±29 nb, respectively

1 data table
Table 1

No description provided.


rivet Analysis
A Measurement of the Reaction $e^+ e^- \to e^+ e^- \eta^\prime$ and the Radiative Width $\Gamma (\eta^\prime \to \gamma \gamma$) at {PETRA}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 113 (1982) 190-194, 1982.
Inspire Record 177090 DOI 10.17182/hepdata.30958

The reaction e + e - → e + e - η' has been observed in the JADE experiment at PETRA, by detecting the final state π + π - γ, resulting from the decay η' → γϱ 0 . The cross section was measured at an average beam energy of 17.15 GeV to be σ(e + e - → e + e - η') = 2.2 ± 0.2 (stat.) ± 0.4(syst.) nb, yielding the radiative width Γ η'γγ = 5.0 ± 0.5(stat.) ± 0.9 (syst.) keV.

1 data table
Table 1

No description provided.


Transverse Momentum Distributions of Hadrons Produced in $\alpha \alpha$ and $\alpha p$ Collisions at the {CERN} Intersecting Storage Rings

The CERN-Heidelberg-Lund collaboration Bell, W. ; Braune, K. ; Claesson, G. ; et al.
Phys.Lett.B 112 (1982) 271-276, 1982.
Inspire Record 176957 DOI 10.17182/hepdata.30920

The inclusive production of charged hadrons has been measured in αα and αp collisions at nucleon-nucleon c.m. energies (√s nn )of 31 and 44 GeV, respectively, for transverse momenta p T up to 5 GeV/ c in the central rapidity ( y ) region. at high p T the yields are consistent with being 4 times and 16 times highere than the ones in pp interactions at y =0, for αp and αα interactions, respectively. However, an enhancement over these factors, as expected from an earlier FNAL experiment, cannot be ruled out.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of Polarized Target Asymmetry in $\gamma d \to p n$ in the Photon Energy Region Between 0.3-{GeV} and 0.7-{GeV}

Ohashi, Y. ; Awaji, N. ; Hayashii, H. ; et al.
Phys.Lett.B 110 (1982) 441-444, 1982.
Inspire Record 176585 DOI 10.17182/hepdata.30974

The target asymmetry in γ d → pn has been measured at proton c.m. angles of 70°, 100° and 130° in the photon energies between 0.3 and 0.7 GeV. Results show relatively small asymmetry values in contrast to large proton polarizations. A phenomenological analysis by Ikeda et al. does not reproduce the present data, especially in the lower energy region.

3 data tables
Table 1

STATISTICAL ERRORS ONLY. MORE DETAILED DATA SUPPLIED BY S.KATO.

Table 2

STATISTICAL ERRORS ONLY. MORE DETAILED DATA SUPPLIED BY S.KATO.

Table 3

STATISTICAL ERRORS ONLY. MORE DETAILED DATA SUPPLIED BY S.KATO.