Muon pair production by electron-positron collisions in the gev region

Borgia, B. ; Ceradini, F. ; Conversi, M. ; et al.
Lett.Nuovo Cim. 3S2 (1972) 115-120, 1972.
Inspire Record 77432 DOI 10.17182/hepdata.37904

None

1 data table

CONST(NAME=EXP/THEORY) is the experimental numbers divided by the theoretical predictions.


Electromagnetic Form-Factors of the Proton at Low Four-Momentum Transfer

Borkowski, F. ; Peuser, P. ; Simon, G.G. ; et al.
Nucl.Phys.B 93 (1975) 461-478, 1975.
Inspire Record 850 DOI 10.17182/hepdata.31992

The 300 MeV electron linear accelerator of Mainz has been used to measure the angular dependence of the electron-proton elastic scattering cross sections at seven different energies for squared four-momentum transfers between 0.13 and 4.7 fm −2 . The proton form factors have been extracted from the cross sections by means of Rosenbluth plots and by fitting parametrized analytical functions directly to the cross sections. The best fit is compared to the data of other laboratories. The previously reported deviations from the dipole fit have been confirmed. From the form factors at q 2 <0.9 fm 2 the proton r.m.s. radius has been determined. A determination of the spectral function of the nucleon isovector form factor G E V in the time-like is obtained using a realistic ϱ resonance.

9 data tables

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Measurement of the Magnetic Structure Function of the Deuteron at q**2 = 1.0-(GeV/c)**2

Martin, F. ; Arnold, R.G. ; Chertok, B.T. ; et al.
Phys.Rev.Lett. 38 (1977) 1320, 1977.
Inspire Record 109585 DOI 10.17182/hepdata.21023

At a square of the momentum transfer of 1.0 (GeV/c)2 the elastic scattering of electrons on deuterons has been measured at electron scattering angles of 8°, 60°, and 82°. From these data we have extracted a value of B(q2)=(0.59±1.20)×10−5 for the deuteron. This measurements extends the range in momentum transfer by almost a factor of 2 over the previous measurements.

2 data tables

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Measurement of muon neutrino and antineutrino scattering off electrons.

Faissner, H. ; Fasold, H.G. ; Frenzel, E. ; et al.
Phys.Rev.Lett. 41 (1978) 213-216, 1978.
Inspire Record 135343 DOI 10.17182/hepdata.20832

Muon-neutrino and -antineutrino scattering off electrons was detected in a 19-ton Al spark chamber, exposed to the wide-band ν (ν¯) beam from the CERN proton synchrotron. The background was determined experimentally. 11 (10) genuine νμ− (ν¯μ−) e scattering events were found. The respective cross sections are (1.1±0.6)×10−42(Eν/GeV) cm2 and (2.2±1.0)×10−42(Eν/GeV) cm2. The analysis excludes a pure V−A interaction, and makes a pure V or A theory improbable. The data agree well with the Salam-Weinberg model and sin2θW=0.35±0.08.

2 data tables

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Electroproduction of Charged Pions in the Quark Fragmentation Region

Drews, G. ; Gebert, W. ; Janata, F. ; et al.
Phys.Rev.Lett. 41 (1978) 1433, 1978.
Inspire Record 131548 DOI 10.17182/hepdata.20866

This paper presents results of an experiment on hadron production in deep-inelastic electron scattering. Good agreement with the predictions of the quark-parton model is found. The Fragmentation functions for u and d quarks into pions are determined, and comparison is made with other deep-inelastic processes and with recent quark jet parametrizations.

1 data table

No description provided.


Experimental Limits on the Strength of Weak Neutral Currents in Lepton Pair Production at {PETRA} Energies

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 99 (1981) 281-286, 1981.
Inspire Record 156813 DOI 10.17182/hepdata.27121

The processes e + e − → e + e − and μ + μ − have been studied at PETRA using the JADE detector. The data, which were collected at s -values of up to 1300 GeV 2 have been analysed in terms of an electro-weak extension of QED to obtain values for the weak vector and axial vector couplings in the lepton sector. The values obtained agree with the predictions of the standard Salam-Weinberg model and the data are further analysed in terms of this model to obtain the limits 0.10 < sin 2 ϑ w < 0.40 (68% CL). The mass of the neutral weak gauge boson is deduced to be greater than 51 GeV/ c 2 .

3 data tables

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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

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.

SEE COMMENT IN PREVIOUS TABLE.

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.


Limit on the B ---> u Coupling from Semileptonic B Decay

The CLEO collaboration Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
Phys.Rev.Lett. 52 (1984) 1084, 1984.
Inspire Record 199380 DOI 10.17182/hepdata.20474

We have used the momentum spectrum of leptons produced in semileptonic B-meson decays to set a 90%-confidence-level upper limit on Γ(b→ulν)Γ(b→clν) of 4%. We also measure the semileptonic branching fractions of the B meson to be (12.0±0.7±0.5)% for electrons and (10.8±0.6±1.0)% for muons.

2 data tables

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A Measurement of the Pion Charge Radius

Amendolia, S.R. ; Badelek, B. ; Batignani, G. ; et al.
Phys.Lett.B 146 (1984) 116-120, 1984.
Inspire Record 201598 DOI 10.17182/hepdata.30511

We report a measurement of the negative pion electromagnetic form factor in the range of space-like four-momentum transfer 0.014 < q 2 < 0.122 (GeV/ c ) 2 . The measurement was made by the NA7 collaboration at the CERN SPS, by observing the interaction of 300 GeV pions with the electrons of a liquid hydrogen target. The form factor is fitted by a pole form with a pion radius of 〈r 2 〈 1 2 = 0.657 ± 0.012 fm.

1 data table

Errors are statistical only.


First Measurement of the Reaction $\pi^- e \to \pi^- \pi^0 e$

Amendolia, S.R. ; Arik, M. ; Badelek, B. ; et al.
Phys.Lett.B 155 (1985) 457-460, 1985.
Inspire Record 213172 DOI 10.17182/hepdata.30413

The first observation of neutral pion production in π e inelastic scattering is presented. The cross section at 300 GeV for | t ‖>62;10 −3 (GeV / c ) 2 is 2.11 ± 0.47 nb, in good agreement with the theory of PCAC anomalies with 3 quark colours.

1 data table

No description provided.