HEPData Search

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.

A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.

Phys.Rev.Lett. 50 (1983) 2051, 1983.

Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables

Table 1

DATA REQUESTED FROM THE AUTHORS.

Table 2

No description provided.

DIFFRACTIVE PRODUCTION OF A NARROW BARYON IN NEUTRON CARBON INTERACTIONS

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Dubna Jinr - 83-602 (83,REC.NOV.) 6p, 1983.

Inspire Record 196394 DOI 10.17182/hepdata.39600

None

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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
Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.

Phys.Lett.B 110 (1982) 82-86, 1982.

Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables

Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.

INCLUSIVE PRODUCTION OF MESONS IN n p INTERACTIONS AT 3.83-GeV/c

Abdivaliev, A. ; Besliu, K. ; Gasparian, A.P. ; et al.

JINR-P1-81-437, 1981.

Inspire Record 167522 DOI 10.17182/hepdata.39060

None

7 data tables

Table 1

Table 2

Table 3

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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.

Date

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CM Energies (GeV)

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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

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

A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

DIFFRACTIVE PRODUCTION OF A NARROW BARYON IN NEUTRON CARBON INTERACTIONS

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

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

rivet Analysis
Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

INCLUSIVE PRODUCTION OF MESONS IN n p INTERACTIONS AT 3.83-GeV/c

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

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