HEPData Search

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Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.

Z.Phys.C 19 (1983) 197, 1983.

Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies$\sqrt s $ between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,$\left\langle {\sqrt s } \right\rangle= 34.6 GeV$, the 1 δ limits 0.12

3 data tables

Table 1

Total cross sections.

Table 2

Angular distribution.

Table 3

Angular distribution.

Experimental Study of the Photon Structure Function F(2) in the High $Q^2$ Region

The JADE collaboration Bartel, W. ; Cords, D. ; Dietrich, G. ; et al.

Phys.Lett.B 121 (1983) 203-208, 1983.

Inspire Record 180758 DOI 10.17182/hepdata.30781

We report on a measurement of the process e + e − →e + e − + hadrons, where one of the scattered electrons is detected at large angles, with an average Q 2 of 23 GeV. The results are analysed in terms of the photon structure function F 2 and are compared with QCD predictions.

3 data tables

Table 1

Data read off graph.

Table 2

Data read off graph.

Table 3

Data read off graph.

Differential Three Jet Cross-section in $e^+ e^-$ Annihilation and Comparison With Second Order Predictions of {QCD} and Abelian Vector Theory

The JADE collaboration Bartel, W. ; Cords, D. ; Dietrich, G. ; et al.

Phys.Lett.B 119 (1982) 239-244, 1982.

Inspire Record 180033 DOI 10.17182/hepdata.30830

Differential three-jet cross sections have been measured in e + e − -annihilation at an average CM energy of 33.8 GeV and were compared to first- and second-order predictions of QCD and of a QED-like abelian vector theory. QCD provides a good description of the observed distributions. The inclusion of second-order effects reduced the observed quark-gluon coupling strength by about 20% to α S = 0.16 ± 0.015 (stat.) ± 0.03 (syst.). The abelian vector theory is found to be incompatible with the data.

2 data tables

Table 1

FIRST ORDER QCD.

Table 2

SECOND ORDER QCD.

Low Mass Electron Pair Anomaly in 17-{GeV}/c $\pi^- P$ Collisions

Stekas, J. ; Abshire, G. ; Adams, M.R. ; et al.

Phys.Rev.Lett. 47 (1981) 1686-1689, 1981.

Inspire Record 172147 DOI 10.17182/hepdata.20624

Inclusive e+e− production in 17-GeV/c π−p collisions has been measured. An excess of e+e− pairs over those from known sources for 0.1<~mee<~0.6 GeV and x<0.5 was found. No evidence is found for enhancements in specific final states involving electrons and photons or charged particles. The photon multiplicity associated with these pairs is measured.

1 data table

Table 1

No description provided.

Measurement of K- p Elastic Differential Cross-Sections Between 610-MeV/c and 943-MeV/c

Adams, C.J. ; Davies, J.D. ; Dowell, J.D. ; et al.

Nucl.Phys.B 96 (1975) 54-66, 1975.

Inspire Record 2402 DOI 10.17182/hepdata.31930

Measurements of K − p elastic scattering have been carried out at 14 momenta between 610 MeV/ c and 943 MeV/ c over the angular range −0.9 < cos θ < 0.9. The results agree well with the best existing data and have significantly smaller errors.

4 data tables

Table 1

No description provided.

Table 2

DIFFERENTIAL CROSS SECTION AT 0 DEG CALCULATED FROM DISPERSION RELATIONS AND AT 180 DEG INTERPOLATED FROM BUBBLE CHAMBER MEASUREMENTS.

Table 3

LEGENDRE POLYNOMIAL FIT, INCLUDING FORWARD AND BACKWARD POINTS.

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Differential Cross-Sections for the Charge Exchange Process pi+ p ---> pi0 (pi+ p) at 8-GeV/c, 16-GeV/c and 23-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg collaboration Baker, P A ; Barnham, Keith W.J. ; Buschbeck, Brigitte ; et al.

Nucl.Phys.B 85 (1975) 31-38, 1975.

Inspire Record 90862 DOI 10.17182/hepdata.32119

The differential cross section d σ d t′ for the charge-exchange process π + p → π 0 ( π + p) at 8, 16 and 23 GeV/ c is presented for several regions of the π + p effective mass. It is found that the dip at t ′ ≈ 0.6 (GeV/ c ) 2 which is observed in the Δ(1236) mass band becomes a less pronounced structure in the higher mass regions. However, while the slope of the d σ d t′ distributions in the near-forward direction decreases strongly with increasing π + p mass, there is no evidence that the observed structure moves to higher values of t ′ as the π + p mass increases. These results are consistent with a Regge-exchange picture where the position of the dip is determined by the exchanged trajectory, but are inconsistent with a simple geometrical picture.

1 data table

Table 1

TP DEPENDENCE FOR FOUR <PI+ P> MASS INTERVALS.

K+ p elastic scattering between 432 and 939 mev/c and phase shift analysis

Adams, C.J. ; Cox, G.F. ; Davies, J.D. ; et al.

Nucl.Phys.B 66 (1973) 36-77, 1973.

Inspire Record 94900 DOI 10.17182/hepdata.32390

Measurements of K + p elastic scattering have been carried out at 13 momenta between 432 MeV/ c and 939 MeV/ c using spark chambers. The data establish unambiguously the constructive interference of the Coulomb and nuclear amplitudes at 432 MeV/ c . The elastic cross section is found to be independent of momentum through the range covered. The phase shifts for S, P, D and F waves are obtained in an energy dependent analysis in which higher waves are held at theoretical values. The initial behaviour ofthe P, D and F amplitudes is quite close to that predicted by the calculation of the peripheral partial waves. Only the P3 and D5 amplitudes become strikingly different with increasing momentum.

14 data tables

Table 1

COULOMB INTERFERENCE EFFECT SEEN AT SMALL ANGLES.

Table 2

No description provided.

Table 3

No description provided.