Andreev, V.
Angular Dependence
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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.


Exclusive Production of Hadron Pairs at Large Momentum Transfer in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 137 (1984) 267-271, 1984.
Inspire Record 194772 DOI 10.17182/hepdata.30576

We report on the exclusive production of π, K and proton pairs from photon-photon interactions at momentum transfers | t |⩾1 GeV 2 . Using the PLUTO detector at the e + e − storage ring PETRA, we have observed 15 events in an integrated luminosity of 41.7 pb −1 . The data lie far below the expectations for point-like hadrons, and are in reasonable agreement with the QCD-based predictions of Brodsky and Lepage.

3 data tables
Table 1

THIS METHOD OF ANALYSIS OF THE OBSERVED RATIO OF HADRON TO MUON PAIRS, IS TIED TO THE SPECIFIC DETECTOR ACCEPTANCE, BUT HAS THE ADVANTAGE OF BEING VIRTUALLY INDEPENDENT OF THE HADRON MASSES.

Table 2

SEE COMMENT IN PREVIOUS TABLE.

Table 3

THIS METHOD OF ANALYSIS OF THE CROSS SECTION AT 90 DEG IN THE CM AS A FUNCTION OF PCM IS MORE EASILY COMPARED WITH THEORETICAL PREDICTIONS BUT MORE DEPENDENT ON THE SPECIFIC HADRON MASSES.


Weak Neutral Currents in e+ e- Collisions at s**(1/2)=29-GeV

Levi, M.E. ; Blocker, C.A. ; Strait, J. ; et al.
Phys.Rev.Lett. 51 (1983) 1941, 1983.
Inspire Record 191845 DOI 10.17182/hepdata.3281

The differential cross sections for lepton pair production in e+e− annihilation at 29 GeV have been measured and found to be in good agreement with the standard model of the electroweak interaction. With the assumption of e−μ−τ universality, the weak neutral-current couplings are determined to be ga2=0.23±0.05 and gv2=0.03±0.04.

8 data tables
Table 1

Numerical values supplied by M.Levi.

Table 2

Data requested from authors.

Table 3

Extrapolated to full angular range.

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A STUDY OF e+ e- ANNIHILATION IN THE 1400-MeV TO 2250-MeV ENERGY RANGE WITH THE MAGNETIC DETECTOR DM2 AT DCI

Augustin, J.E. ; Ayach, L. ; Calcaterra, A. ; et al.
LAL-83-21, 1983.
Inspire Record 192321 DOI 10.17182/hepdata.13242

None

5 data tables
Table 1

ASSUMING ABS(GE)=ABS(GM).

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
>A Measurement of $e^+ e^- \to \bar{p} p$ for 1975-{MeV} $\le \sqrt{s} \le$ 2250-{MeV}

Bisello, D. ; Limentani, S. ; Nigro, M. ; et al.
Nucl.Phys.B 224 (1983) 379, 1983.
Inspire Record 190558 DOI 10.17182/hepdata.33935

The e + e − → p p cross section has been measured in the energy interval (1975 ⩽ 2 E ⩽ 2250) MeV for |cos θ | < 0.7. The measurement is based on ∼ 100 events, thus improving by a factor 3 on the previous existing statistics in this energy interval. The form factor | G | 2 is given as a function of energy under the assumption | G E | = | G M |. We also give the first measurement of the differential cross section, averaged over the energy interval, and estimate the ratio G M |/| G E | from it.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


The Influence of Fragmentation Models on the Determination of the Strong Coupling Constant in $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Nucl.Phys.B 218 (1983) 269-288, 1983.
Inspire Record 179447 DOI 10.17182/hepdata.8172

Hadronic events obtained with the CELLO detector at PETRA were compared with first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model. Both models are in reasonable agreement with the data, although they do not completely reproduce the details of many distributions. Several methods have been applied to determine the strong coupling constant α S . Although within one model the value of α S varies by 20% among the different methods, the values determined using the Lund model are 30% or more larger (depending on the method used) than the values determined with the Hoyer model. Our results using the Hoyer model are in agreement with previous results based on this approach.

3 data tables
Table 1

DATA CORRECTED WITH HOYER MODEL (ALPHA-S=0.15).

Table 2

DATA CORRECTED WITH LUND MODEL (ALPHA-S=0.25).

Table 3

No description provided.


rivet Analysis
Analysis of the Energy Weighted Angular Correlations in Hadronic $e^+ e^-$ Annihilations at 22-{GeV} and 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 95, 1982.
Inspire Record 12010 DOI 10.17182/hepdata.16413

Measurements of energy weighted angular correlations in electron positron annihilations at c.m. energies of 22 GeV and 34 GeV are presented.

4 data tables
Table 1

ENERGY-ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

Table 2

ENERGY-ENERGY CORRELATIONS FOR PRIMORDIAL HADRONS.

Table 3

ASSYMETRY IN ENERGY CORRELATIONS FOR FINAL STATE PARTICLES.

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rivet Analysis
Energy-energy Correlations in $e^+ e^-$ Annihilation Into Hadrons

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 292, 1981.
Inspire Record 156315 DOI 10.17182/hepdata.6228

Measurements of energy-energy correlations in hadronic final states produced in e + e − annihilation at c.m. energies between 7.7 and 31.6 GeV are presented. The data are compared to perturbative QCD predictions. Good qualitative agreement above 20 GeV c.m. energy is found. The importance of non-perturbative effects is discussed, as well as the detailed behaviour of the correlation near 180°.

6 data tables
Table 1

No description provided.

Table 2

OPPOSITE SIDE ENERGY-ENERGY CORRELATIONS NEAR 180 DEG.

Table 3

ENERGY-ENERGY CORRELATION INTEGRATED IN THE REGION 60 TO 120 DEG.

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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.


Test of {QED} in the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 4 (1980) 269, 1980.
Inspire Record 152289 DOI 10.17182/hepdata.15600

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.