Levi Sandri, P.
SIG/SIG
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Electroproduction of rho0 mesons at 1.5 > q-squared > 0.3 gev-squared and 2.8 > w > 1.7 gev

Eckardt, V. ; Gebauer, H.J. ; Joos, P. ; et al.
Phys.Lett.B 43 (1973) 240-244, 1973.
Inspire Record 84944 DOI 10.17182/hepdata.28153

Production and decay characteristics of electroproduced rho mesons were studied in the final state epπ + π − .

1 data table
Table 1

No description provided.


Observation of single pion production by a weak neutral current.

Barish, S.J. ; Cho, Y. ; Derrick, M. ; et al.
Phys.Rev.Lett. 33 (1974) 448, 1974.
Inspire Record 89586 DOI 10.17182/hepdata.51354

In exposures of the Argonne National Laboratory 12-ft bubble chamber filled with hydrogen and deuterium to a neutrino beam, we have observed events consisting of (1) a single π+ meson originating in the liquid, and (2) a proton with an e+e− pair pointing to it. Only a small fraction of these events can be ascribed to known reactions such as np→nnπ+ and np→npπ0. The remaining events, which correspond to a signal of about 4.5 standard deviations, we ascribe to the reactions νp→νnπ+ and νpπ0.

1 data table
Table 1

No description provided.


Measurement of the Branching Ratio gamma (anti-p p --> e+ e-) / gamma (anti-p p --> Total) in anti-Proton-Proton Annihilation at Rest

Bassompierre, G. ; Binder, G. ; Dalpiaz, P. ; et al.
Phys.Lett.B 64 (1976) 475-478, 1976.
Inspire Record 109375 DOI 10.17182/hepdata.27616

Analyzing a sample of 220 000 events from an experiment still in progress at the CERN Proton Synchrotron (PS), 60 pairs of electrons with an energy above 700 MeV have been observed. The electrons, produced by annihilation of antiprotons stopped in a liquid-hydrogen target, are detected with optical spark chambers and scintillation counters. Twenty-nine out of these 60 pairs have been found to be collinear; normalizing with respect to the hadronic two-body channels π + π − and K + K − , a braching ratio B ee =Γ( p ̄ p → e + e − )/Γ( p ̄ p → total ) = (3.2 ± 0.9) × 10 −7 has been obtained

1 data table
Table 1

No description provided.


Precision Comparison of Inelastic electron and Positron Scattering from Hydrogen

Fancher, D.L. ; Caldwell, David O. ; Cumalat, John P. ; et al.
Phys.Rev.Lett. 37 (1976) 1323, 1976.
Inspire Record 4108 DOI 10.17182/hepdata.21910

Using 13.5-GeV beams at Stanford Linear Accelerator Center, we have compared electron and positron inelastic scattering over the range 1.2<|q2|<3.3 (GeV/c)2, 2<ν<9.5 GeV for the four-momentum and energy transfers, respectively. We find the ratio of the cross sections to be e+e−=1.0027±0.0035 (including statistical and systematic effects), with no significant dependence on q2 or ν. This result has appreciably smaller errors than previous attempts to find two-photon-exchange effects in electron or muon scattering.

1 data table
Table 1

No description provided.


Study of Neutrino Proton Elastic Scattering in the GARGAMELLE Freon Experiment

Pohl, M. ; Welch, L. ; Dewit, M. ; et al.
Phys.Lett.B 72 (1978) 489-492, 1978.
Inspire Record 122236 DOI 10.17182/hepdata.48973

The cross section ratio of the elastic neutral current reaction ν p→ ν p to the quasi-elastic charged current reaction ν n→ μ − p has been measured in the kinematical region 0.3⩽ q 2 ⩽1.0 (GeV/ c ) 2 . The measured value is R M =0.17±0.08. Model dependent corrections are applied, especially for ν n→ ν n contamination, and the result is compared to various models.

1 data table
Table 1

(C=OBSERVED) and (C=CORRECTED) are the observed and corrected for the nuclear effects ratios.


Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.
Phys.Rev.Lett. 42 (1979) 1113, 1979.
Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inclusive $\rho^0$ Production in Anti-neutrino $p$ Charged Current Interactions

Derrick, M. ; Gregory, P. ; Lopinto, F. ; et al.
Phys.Lett.B 91 (1980) 307-310, 1980.
Inspire Record 8534 DOI 10.17182/hepdata.6495

Using data from the Fermilab 15 ft hydrogen bubble chamber, we have studied inclusive ϱ 0 production in antineutrino-proton charged-current interactions. We measure (0.21 ± 0.03) ϱ 0 /event, corresponding to ϱ 0 / π − =0.12 ± 0.02. As a function of Q 2 and for hadronic masses above a threshold region, the ϱ 0 / π − ratio shows little variation. At least 50% of the ϱ 0 's are consistent with coming from the current fragmentation region. The results agree reasonably well with the predictions of the quark fragmentation model of Feynman and field.

4 data tables
Table 1

AVERAGE BEAM ENERGY 31 GEV.

Table 2

No description provided.

Table 3

No description provided.

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Test of {QED} in $e^+ e^-$ Annihilation at Energies Between 12-{GeV} and 31.6-{GeV}

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 259-265, 1980.
Inspire Record 153127 DOI 10.17182/hepdata.45228

We have measured the reactions e + e − → e + e − → μ + μ − and e + e − → γγ at c.m. energies between 12 and 31.6 GeV. Excellent agreement with the predictions of QED has been found, resulting in cut off parameters Λ + > 112 GeV and Λ − > 139 GeV for the first process and Λ + > 34 GeV and Λ − > 42 GeV (95% c.1.) for the last one. A limit on the Weinberg angle of sin 2 θ W < 0.55 (95% c.1.) has been obtained.

3 data tables
Table 1

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 2

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 3

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.


High Statistics Study of ($\sim$ 10$^6$ events) of $J/\psi$ Production and $\Upsilon$ Production in the energy range 150 to 280 GeV by $\pi^\pm$, $p^\pm$ incident particle

The Saclay-CERN-College de France-Ecole Poly-Orsay collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
AIP Conf.Proc. 68 (1981) 201-204, 1981.
Inspire Record 154782 DOI 10.17182/hepdata.49656

We have performed in the NA3 experiment the study of high mass dimuon production by a hadronic unseparated beam on hydrogen and platinum targets. The comparison of the production cross‐section for proton and antiproton together with the differential cross‐section dσ/dx allows us to compare the data with a production mechanism involving quark‐antiquark and gluon‐gluon interactions. The cosΘ* distribution of the same J/ψ data have also been analysed and results will be presented. Finally we have observed T production from 150 GeV/c incident pions.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

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Multiplicity, Momentum and Angular Characteristics of $\pi^-$ Mesons for $p$ C, $d$ C, $\alpha$ C and C C Interactions at 4.2-{GeV}/$c$ Per Nucleon

The Alma Ata-Baku-Belgrade-Bucharest-Dubna-Kishinev-Leipzig- Moscow-Prague-Samarkand-Sofiya-Tashkent-Tbilisi-Ulan Bator-Varna collaboration Agakishiev, G.N. ; Akhababian, N. ; Armutliisky, D. ; et al.
Z.Phys.C 27 (1985) 177, 1984.
Inspire Record 203342 DOI 10.17182/hepdata.1999

Light ion collisions with carbon target at 4.2 GeV/c/N are studied. Pion multiplicity distributions, momentum and angular spectra are analysed. These data are described in terms of models assuming independent interactions of nucleons from the projectile nucleus with the target.

18 data tables
Table 1

No description provided.

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