Date

Total Cross-Section for Hadron Production by electron-Positron Annihilation Between 2.4-GeV and 5.0-GeV Center-Of-Mass Energy

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 764, 1975.
Inspire Record 100592 DOI 10.17182/hepdata.21227

The total cross section for hadron production by e+e− annihilation has been measured at center-of-mass energies between 2.4 and 5.0 GeV. Aside from the very narrow resonances ψ(3105) and ψ(3695), the cross section varies between 32 and 17 nb over this region with structure in the vicinity of 4.1 GeV.

2 data tables

No description provided.

MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.


Measurement of e+ e- ---> e+ e- and e+ e- ---> mu+ mu- at SPEAR

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 233, 1975.
Inspire Record 91755 DOI 10.17182/hepdata.21210

The reactions e+e−→e+e− and e+e−→μ+μ− have been measured at center-of-mass energies 3.0, 3.8, and 4.8 GeV and production angles of 50°<θ<130° over all azimuthal angles. Agreement with quantum electrodynamics is excellent. New limits for cutoff parameters in quantum-electrodynamic-breakdown models are given.

2 data tables

No description provided.

No description provided.


Discovery of a Narrow Resonance in $e^+ e^-$ Annihilation

The SLAC-SP-017 collaboration Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 33 (1974) 1406-1408, 1974.
Inspire Record 91761 DOI 10.17182/hepdata.21247

We have observed a very sharp peak in the cross section for e+e−→hadrons, e+e−, and possibly μ+μ− at a center-of-mass energy of 3.105±0.003 GeV. The upper limit to the full width at half-maximum is 1.3 MeV.

1 data table

No description provided.


Preliminary Result of Frascati (ADONE) on the Nature of a New 3.1-GeV Particle Produced in e+ e- Annihilation

Bacci, C. ; Celio, R.Balbini ; Berna-Rodini, M. ; et al.
Phys.Rev.Lett. 33 (1974) 1408, 1974.
Inspire Record 90991 DOI 10.17182/hepdata.21293

We report on the results at ADONE to study the properties of the newly found 3.1-BeV particle.

1 data table

No description provided.


Anti-Nucleon Production in Colliding e+ e- Beams at SPEAR

Berk, D. ; Buchanan, C.D. ; Drickey, Darrell James ; et al.
Lett.Nuovo Cim. 9 (1974) 475-478, 1974.
Inspire Record 3185 DOI 10.17182/hepdata.37333

None

1 data table

ONE EVENT SEEN - PROBABLY AN ANTIPROTON.


Electron-Positron Elastic Scattering at 5-GeV Center-Of-Mass Energy

Newman, H. ; Averill, R. ; Eshelman, J. ; et al.
Phys.Rev.Lett. 32 (1974) 483, 1974.
Inspire Record 744 DOI 10.17182/hepdata.21306

We have measured the cross section, the distribution of scattering angles, and the distribution of noncoplanarity angles for electron-positron elastic scattering at 5 GeV c. m. energy. An analysis based on 230 events with scattering angles between 50 and 130° yields a ratio of the experimental to theoretical quantum-electrodynamic cross section of 1.03 ± 0.09. The scattering-angle and noncoplanarity-angle distributions are also found to be in excellent agreement with the quantum-electrodynamic predictions.

1 data table

No description provided.


Hadron Production by electron-Positron Annihilation at 5-GeV Center-Of-Mass Energy

Tarnopolsky, G. ; Eshelman, J. ; Law, M.E. ; et al.
Phys.Rev.Lett. 32 (1974) 432-435, 1974.
Inspire Record 745 DOI 10.17182/hepdata.21302

We have measured the cross section σ for electron - positron annihilation into three or more hadrons, with at least two charged particles in the final state, at 5 GeV center-of-mass energy. We find a model-independent lower limit of σ>9.1±1.0nb; assuming invariant phase-space production of pions, we calculate the detection efficiency of our detector to be (45 ± 11)%, yielding a cross section σ=21±5nb. The average charged hadron multiplicity is found to be n¯=4.3±0.6.

1 data table

No description provided.


Multihadron production through the photon-photon interaction

Paoluzi, L. ; Ceradini, F. ; Ferrer, M.L. ; et al.
Lett.Nuovo Cim. 10S2 (1974) 435-439, 1974.
Inspire Record 96130 DOI 10.17182/hepdata.37454

None

1 data table

TWO EVENTS SEEN WITH MASSES 800 +- 90 MEV AND 1400 +- 90 MEV. THE FIRST WHEN INTERPRETED AS ETAPRIME PRODUCTION GIVES A WIDTH OF 11, +15, -8 KEV FOR ETAPRIME --> 2GAMMA USING THE EQUIVALENT PHOTON APPROXIMATION.


Experimental Results on the Production And Decay Modes of the 3101 MeV Resonance at #techn{ADONE}

Baldini-Celio, R. ; Bacci, C. ;
Lett.Nuovo Cim. 11 (1974) 711, 1974.
Inspire Record 98139 DOI 10.17182/hepdata.37446

None

1 data table

HADRONIC WIDTH IS 26 +- 11 KEV, ELECTRON DECAY WIDTH IS 3.4 +- 1.2 KEV AND MUON DECAY WIDTH IS 2.4 +- 1.1 KEV.


Multihadron production in e+ e- collisions up to 3 gev total center-of-mass energy

Ceradini, F. ; Conversi, M. ; D' Angelo, S. ; et al.
Phys.Lett.B 47 (1973) 80-84, 1973.
Inspire Record 95215 DOI 10.17182/hepdata.28037

New results on the multihadron production by electron and positron beams colliding with a total energy of up to 3 GeV are reported. Disregarding possible kaon final states, the ratio σ mh / σ μμ of the total multihadron cross-section to the point-like cross section for process e + e − → μ + μ − has an average value of 1.58 ± 0.25 in the energy interval 2.6–3.0 GeV. The average charged multiplicity over this energy range is 〈 n c 〉 = 2.9 ± 0.3.

1 data table

AT A MEAN ENERGY OF 2.85 GEV, THE AVERAGE MULTIHADRON CROSS SECTION IS 16.4 +- 2.6 NB (R = 1.58 +- 0.25).