Allasia, D.
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A Study of Elastic Photoproduction of Low Mass K$^{+} $K$^{-}$ Pairs From Hydrogen in the Energy Range 2.8-{GeV} to 4.8-{GeV}

Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Z.Phys.C 12 (1982) 1, 1982.
Inspire Record 168200 DOI 10.17182/hepdata.16435

The results of an experiment to study elasticK+K− photoproduction are presented. Differential cross sections and spin density matrix elements for ϕ(1.019) production are stddied as a function of incident photon energy and over a wide range of momentum transfer,t (tmin>t>−1.5(GeV/c)2). Helicity conserving amplitudes are observed to dominate ϕ production throughout this range and the differential cross sections exhibit a forward diffractive peak which cannot be understood in terms of a simple exponential dependence. A new value of the photon ϕ coupling constant is determined and shown to be consistent withe+e− annihilation measurements. A detailed study of the energy dependence of the differential cross sections is made, including other experimental data, and the extracted effective Regge trajectory compared with other diffractive processes. A study of the dependence of theK+K− decay angular distribution on invariant mass reveals evidence for ans wave contribution interfering with thep wave ϕ which may be attributable to theS* meson.

3 data tables
Table 1

LOWER LIMIT OF ABS(T) IN TABLE IS TMIN.

Table 2

No description provided.

Table 3

LOW T VARIATION WITH ELAB. LOWER LIMIT OF ABS(T) IN TABLE IS TMIN.


Proton - Deuteron Elastic Scattering From 20-{GeV} to 210-{GeV}

Warren, G. ; Gross, D. ; Olsen, S.L. ; et al.
Nucl.Phys.B 207 (1982) 365-373, 1982.
Inspire Record 11268 DOI 10.17182/hepdata.34079

Measurements of the differential cross section for proton-deuteron elastic scattering are reported for incident proton momenta ranging from 20 to 210 GeV and for invariant four-momentum transfers of 0.6 ≤ − t ≤ 3.0 GeV 2 . The results are in disagreement with a very simple Glauber double scattering model calculation.

1 data table
Table 1

Axis error includes +- 5/5 contribution (ERROR IN RECONSTRUCTION EFFICIENCY AND ACCEPTANCE CALCULATION).


CHARM PARTICLE PRODUCTION IN 360-GeV pi- p AND 360-GeV p p INTERACTIONS

The Amsterdam-Brussels-CERN-Madrid-Mons-Nijmegen-Oxford-Padua- Paris-Rutherford-Serpukhov-Stockholm-Strasbourg-Turin-Trieste collaboration Aguilar-Benitez, M. ; Allison, W. ; Bagnaia, P. ; et al.
IFVE-81-165, 1981.
Inspire Record 169453 DOI 10.17182/hepdata.34204

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
Phys.Lett.B 110 (1982) 82-86, 1982.
Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables
Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.


rivet Analysis
Study of the $e^+ e^- \to \pi^+ \pi^- \pi^+ \pi^-$ Reaction in the 1.4-{GeV} to 2.18-{GeV} Energy Range

Cordier, A. ; Bisello, D. ; Bizot, J.C. ; et al.
Phys.Lett.B 109 (1982) 129-132, 1982.
Inspire Record 168552 DOI 10.17182/hepdata.30995

New measurements of thee + e − → π + π − π + π − cross section have been performed by the magnetic detector DM1 at DCI (ORSAY) in the 1.4−2.18 GeV total energy range with statistics of 11000 events. Assuming the4 π ± production is dominated by the ϱ′(1.6) we determine its parameters: M = 1.57 ± 0.02 (stat.) −0.00 +0.06 (syst.) GeV,Γ = 0.51 ± 0.04 (stat.) −0.01 +0.04 (syst.)GeV,Γ ρ ′ee B ϱ′→ ρ 0 π + π − = 2.67 ± 0.19 (stat.) −0.36 +0.27 (syst.)keV.

1 data table
Table 1

No description provided.


rivet Analysis
$\pi^0$ Production by $e^+ e^-$ Annihilation at 14-{GeV} and 34-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 108 (1982) 71-76, 1982.
Inspire Record 168232 DOI 10.17182/hepdata.31018

The process e + e − → π 0 + anything has been measured at c.m. energies of 14 and 34 GeV for π 0 energies between 0.5 and 4 GeV. The ratio of π 0 to π ± production for π momenta between 0.5 and 1.5 GeV/ c is measured to be 2 σ ( π 0 )/ [ σ ( π + ) + σ ( π − )] = 1.3 ± 0.4 (1.2 ± 0.4) at 14 (34) GeV. The scaled cross section ( s / μ )d σ /d x when compared with lower energy (4.9–7.4 GeV) π 0 data indicates a substantial scaling violation.

3 data tables
Table 1

COMPARISON OF PI0 WITH CHARGED PION CROSS SECTIONS (SCALED BI 1/S TO SAME ENERGIES).

Table 2

No description provided.

Table 3

No description provided.


A Comparison of $\bar{p} p$ and $p p$ Interactions in the Central Region at $\sqrt{s}=53$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 108 (1982) 58-62, 1982.
Inspire Record 168036 DOI 10.17182/hepdata.31012

The inclusive production cross sections of pions, kaons, protons, and antiprotons in p p and pp interactions at √ s =53 GeV are compared in the kinematic range | y | < 0.8 and p T < 1.5 GeV/ c . We observe differences in the K + /K − and p /p ratios for the two data samples. Although the bulk of the particles are produced with the same momentum and rapidity distributions in p p and pp collisions, we observe difference in these distributions for produced protons and antiprotons.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Observation of a Charge Asymmetry in $e^+ e^- \to \mu^+ \mu^-$

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 108 (1982) 140-144, 1982.
Inspire Record 168234 DOI 10.17182/hepdata.31023

The angular distribution and the s dependence of the total cross section for the process e + e − → μ + μ − have been measured using the JADE detector at PETRA. After radiative corrections, a forward-backward asymmetry of −(11.8±3.8) % was observed at an average centre of mass energy of 33.5 GeV. For comparison, an asymmetry of −7.8 % is expected on the basis of the standard Glashow-Salam-Weinberg model.

5 data tables
Table 1

Best fit to total cross section in energy range.

Table 2

ANGULAR DISTRIBUTION.

Table 3

Forward-backward asymmetry within the acceptnce region.

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Measurement of the Ratios of $\bar{\nu}_\mu n$ to $\bar{\nu}_\mu p$ Charged Current Cross-sections at High-energies

Allasia, D. ; Angelini, C. ; Baldo-Ceolin, M. ; et al.
Phys.Lett.B 107 (1981) 148-152, 1981.
Inspire Record 167732 DOI 10.17182/hepdata.39982

From the analysis of 5630 v υ and of 1372 v π charged current interactions, obtained in the BEBC bubble chamber filled with deuterium and exposed to the CERN wide band antineutrino beam, the ratios of cross section on neutron and photon targets have been measured and found to be R  σ ν)/σ v p = 0.51 ± 0.01 (±0.03) , and R  σ( ν n )/σ( v p ) = 22.2 ± 0.12 (±0.25) The dependence of these ratios on the x scaling variable shows, in a direct way, that the momentum distribution of the majority quark, u p ( x ) = d n ( x ), is broader than that of the minority quark, u n ( x ) = d p ( x ).

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Analysis of Fragmentation Functions of Narrow Band Neutrino and Anti-neutrino Interactions on an Isoscalar Target

The Aachen-Bonn-CERN-Democritos-London-Oxford-Saclay collaboration Deden, H. ; Fritze, P. ; Grassler, H. ; et al.
Nucl.Phys.B 198 (1982) 365-379, 1982.
Inspire Record 11149 DOI 10.17182/hepdata.34174

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.