Learned, J.G.
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Production of High Mass Muon Pairs in $\pi^-$ Be Collisions at 150-{GeV}/$c$ and 175-{GeV}/$c$

Barate, R. ; Bareyre, P. ; Bonamy, P. ; et al.
Phys.Rev.Lett. 43 (1979) 1541, 1979.
Inspire Record 142156 DOI 10.17182/hepdata.20768

This paper presents production and decay characteristics of 500 high-mass, high-resolution μ+μ− pairs produced in π− Be collisions at 150 and 175 GeV/c. The data do not agree with a simple Drell-Yan production mechanism, but indicate that higher-order quantum-chromodynamic corrections must be included.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Study of Electron - Positron Collisions at the Highest {PETRA} Energy

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Lett.B 85 (1979) 463-466, 1979.
Inspire Record 141976 DOI 10.17182/hepdata.27332

We report on the results of the study of e + e − collisions at the highest PETRA energy of √ s = 31.57 GeV, using the 4π sr, electromagnetic and calorimetric detector Mark J. Based on 88 hadron events, and an integrated luminosity of 243 nb −1 we obtain R = σ (e + e − → hadrons)/ σ (e + e − → μ + μ − ) = 4.0 ± 0.5 (statistical) ± 6 (systematic). The R value, the measured thrust distribution and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

CORRECTIONS FOR TWO-PHOTON PROCESSES, TAU HEAVY LEPTON PRODUCTION AND INITIAL STATE RADIATIVE CORRECTIONS HAVE BEEN APPLIED.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 31.57 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Cross-sections for Charged Current Neutrino and Anti-neutrino Interactions in the Energy Range 10-{GeV} to 50-{GeV}

Colley, D.C. ; Jones, G.T. ; O'Neale, S. ; et al.
Z.Phys.C 2 (1979) 187, 1979.
Inspire Record 141975 DOI 10.17182/hepdata.16366

Charged-current neutrino and antineutrino interaction cross sections have been measured in the energy range 10 to 50 GeV using BEBC filled with a neon-hydrogen mixture. At these energies, σ/E was measured to be (0.73±0.08) 10−38 cm2/GeV per nucleon for neutrinos and (0.32±0.06) 10−38 cm2/GeV per nucleon for antineutrinos.

2 data tables
Table 1

Axis error includes +- 9/9 contribution (NEUTRAL CURRENT EVENTS AND NEUTRAL HADRON INDUCED REACTIONS, LOSSES OF EVENTS WITH ONLY ONE VISIBLE CHARGED PARTICLE).

Table 2

Axis error includes +- 9/9 contribution (NEUTRAL CURRENT EVENTS AND NEUTRAL HADRON INDUCED REACTIONS, LOSSES OF EVENTS WITH ONLY ONE VISIBLE CHARGED PARTICLE).


Study of Electron - Positron Collisions at the Center-of-mass Energies of 27.4-{GeV} and 27.7-{GeV} at {PETRA}

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 901, 1979.
Inspire Record 141542 DOI 10.17182/hepdata.20739

This paper reports on the first results of the study of e+e− collisions at s=27.4 GeV and s=27.7 GeV at PETRA, using the 4π-sr electromagnetic and calorimetric detector MARK-J. We obtain an average R=σ(e+e−→hadrons)σ(e+e−→μ+μ−)=3.8±0.3 (statistical)±0.6 (systematic) and a relative R=1.0±0.2 between the two energies. The R values, the measured thrust distribution, and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

THE RELATIVE VALUE OF R BETWEEN THESE TWO ENERGIES IS 1.0 +- 0.2.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 13, 17 AND 27 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


A Measurement of the Anti-neutron - Proton Cross-section as Low-energy

Gunderson, B. ; Learned, J. ; Mapp, J. ; et al.
Phys.Rev.D 23 (1981) 587, 1981.
Inspire Record 8075 DOI 10.17182/hepdata.24071

The total and annihilation cross sections of antineutrons on protons and carbon nuclei have been measured for antineutron momenta 0.25 to 0.88 GeV/c using a novel poor-geometry transmission technique. The measured cross sections are similar to antiproton cross sections in the same energy region. The presence of higher angular momenta (≥P wave) in the annihilation is confirmed down to 0.25 GeV/c. The Glauber-Wilkin correction to the p¯d total cross section is verified to 20% precision in this momentum region.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (QUOTED ERRORS INCLUDE BOTH STATISTICAL AND SYSTEMATIC EFFECTS).


Measurements of the Double Polarization Parameters $G$ and $H$ in Neutral Pion Photoproduction

Bussey, P.J. ; Rutherglen, J.G. ; Booth, P.S.L. ; et al.
Nucl.Phys.B 159 (1979) 383-396, 1979.
Inspire Record 141663 DOI 10.17182/hepdata.34624

Measurements have been made of the double polarisation parameters G and H in the photoproduction of neutral pions from protons, for incident photon energies between 1300 MeV and 2300 MeV and for pion c.m. angles between 50δ and 80δ. The results are compared with predictions from a recent comprehensive analysis of earlier photoproduction data.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Polarization Parameters in Positive Pion Photoproduction

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Nucl.Phys.B 154 (1979) 205-225, 1979.
Inspire Record 140382 DOI 10.17182/hepdata.43832

Measurements have been made of the polarisation parameters Σ , T and P for the process γ p → π + n in the photon energy range 520–2250 MeV at c.m. angles between 30° and 120°. These data were obtained in a double polarisation experiment, using the polarised photon beam from the Daresbury electron synchrotron incident on a polarised proton target. The data are compared with predictions from current theoretical analyses.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Polarization Parameters in Neutral Pion Photoproduction

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Nucl.Phys.B 154 (1979) 492-502, 1979.
Inspire Record 140230 DOI 10.17182/hepdata.34681

The polarisation parameters Σ, P and T have been measured for the process γ p→ π 0 p in the photon energy range 1300–2100 MeV and c.m. angles between 30° and 110°, in an experiment with a polarised beam and polarised target. The results are compared with a recent theoretical analysis which fits data from threshold to 16 GeV. The new data are in general agreement with the analysis, but with some significant discrepancies in detail.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Test of Quantum Electrodynamics at {PETRA} Energies

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 42 (1979) 1110, 1979.
Inspire Record 140093 DOI 10.17182/hepdata.20817

We report on the measurement of the reaction e+e−→e+e− with a large—solid-angle electromagnetic shower detector at center-of-mass energies s=13 and 17 GeV. Comparison of our results with predictions of quantum electrodynamics shows excellent agreement in both the angular distribution and energy dependence. Values of cutoff parameters are also given.

1 data table
Table 1

No description provided.


Production of $\psi$ and $\psi^\prime$ Mesons in $\pi^- N$ Scattering at 150-{GeV}/$c$

Abolins, M.A. ; Barate, R. ; Bareyre, P. ; et al.
Phys.Lett.B 82 (1979) 145, 1979.
Inspire Record 133175 DOI 10.17182/hepdata.27333

In a large-acceptance spectrometer, muon pairs and associated hadrons were observed with μμ masses up to 10 GeV/ c 2 and ΔM M = 0.015 resolution. We report here on the production of 4000 J/ ψ and 80 ψ ′ mesons.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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