Atkinson, M.
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Composition of Particles Emitted at Large $p_T$ and Medium Angles in $p p$, $d d$, and $\alpha \alpha$ Collisions at the {CERN} Intersecting Storage Rings

The Ames-Bologna-CERN-Dortmund-Heidelberg-LBL-Lund-Warsaw collaboration Breakstone, A. ; Claesson, G. ; Crawley, H.B. ; et al.
Z.Phys.C 30 (1986) 507, 1986.
Inspire Record 218607 DOI 10.17182/hepdata.15905

The relative yields of kaons and protons compared with the yield of pions at highpT and polar angles θ away from 90° (in the range from 10° to 45°) are presented forpp, dd, and αα interactions at a centre-of-mass energy\(\sqrt {s_{NN} }= 31\) GeV per nucleon-nucleon collision. The measured particle ratios depend on the atomic mass numberA of the beam particles and on θ. TheA dependence of the ratios becomes stronger for largerpT and is more pronounced at smaller polar angles.

4 data tables
Table 1

ERRORS ARE PURELY STATISTICAL.

Table 2

ERRORS ARE PURELY STATISTICAL.

Table 3

ERRORS ARE PURELY STATISTICAL.

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Study of $\eta \pi^+ \pi^-$ States in the $\rho^\prime$ (1600) Mass Region Photoproduced in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 30 (1986) 531, 1986.
Inspire Record 218611 DOI 10.17182/hepdata.15991

In diffractive photoproduction ofηπ+π−, the two-body substatesηρ0 andA2π are found to contribute significantly to the cross-section forηπ+π− masses below 2.4 GeV. From a spin-parity analysis the branching ratio, ρ′(1600)→ηρ/ρ′(1600)→, is determined to be <0.02 at the 68.3% confidence level. TheA2π component shows an enhancement around 1.7 GeV. The spin-parity analysis indicates a probable contribution to this signal from exclusive photoproduction of theg(1690).

6 data tables
Table 1

No description provided.

Table 2

Not corrected for 35% background under the eta --> gamma gamma peak.

Table 3

Not corrected for 35% background under the ETA --> GAMMA GAMMA peak.

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Anti-proton - Proton Elastic Cross-sections in the Momentum Range Between 180-{MeV}/$c$ and 600-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 166 (1986) 113-118, 1986.
Inspire Record 217928 DOI 10.17182/hepdata.30308

Differential cross sections for p̄p elastic scattering have been measured in the full angular range for the p̄ momenta between 180 and 600 MeV/ c . It is found that s- and p-wave scattering is dominant below 300 MeV/ c . The s-wave component in the total cross section is 40–60% below 300 MeV/ c , in contrast to the NN scattering where it is about 90%. The s-, p- and d-wave scattering amplitudes are derived.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Direct Photon Pair Production From Pions and Protons at 200-{GeV}/$c$

The NA3 collaboration Badier, J. ; Bardadin-Otwinowska, M. ; Bemporad, C. ; et al.
Phys.Lett.B 164 (1985) 184-188, 1985.
Inspire Record 217947 DOI 10.17182/hepdata.30329

We present results from a direct photon pair search performed with the NA3 spectrometer, using incident positive and negative beams at 200 GeV/ c interacting with a carbon target. The experiment is sensitive to photons with p T >1.8 GeV / c and −0.4⩽y ∗ ⩽1.0 , one in each arm of the apparatus. A 3 standard deviation signal is seen in τ − and p interactions. The cross section is higher than the second order QCD calculations, but systematic errors are large.

1 data table
Table 1

No description provided.


HADRON MULTIPLICITY VARIATION WITH Q**2 AND SCALE BREAKING OF THE HADRON DISTRIBUTIONS IN DEEP INELASTIC MUON - PROTON SCATTERING

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Phys.Lett.B 165 (1985) 222-228, 1985.
Inspire Record 217810 DOI 10.17182/hepdata.30328

Measurements are presented of the variation with Q 2 (scaling violation) of the hadron multiplicity in deep inelastic muon-proton scattering. An increase in the average multiplicity of both the charged hadrons and K 0 mesons is observed with increasing Q 2 or x Bj for fixed centre-of-mass energy W . The study of the shape of the effective fragmentation function D h ( z , W , Q 2 ) shows that the increase of the particle yield with Q 2 takes place for low z particles. The variation of the hadron distributions with Q 2 is also studied in the current fragmentation region where a decrease in multiplicity is observed. Such effects are expected from QCD.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inclusive Charged Particle Production Near the Kinematic Limit in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.
Phys.Lett.B 164 (1985) 199-202, 1985.
Inspire Record 17255 DOI 10.17182/hepdata.30327

Inclusive production of charged particles has been studied in e + e − annihilation at s s=29 GeV using the high resolution spectrometer at PEP. Differential cross sections are presented in the range of scaled energy 0.1< z <1.0. The data for z <0.5 show the (1− z ) 2 behavior predicted by the dimensional counting rules. Comparisons are made with predictions of the Lund string model and the Webber cluster model.

1 data table
Table 1

Data requested from authors.


A Study of the Inclusive $K_s^0$, $\Lambda$, $\bar{\Lambda}$ Production in Diffractive $\gamma$P Interactions

Bhadra, S. ; Appel, J.A. ; Bartlett, D.F. ; et al.
Phys.Rev.Lett. 55 (1985) 2749, 1985.
Inspire Record 217669 DOI 10.17182/hepdata.20275

We have studied inclusive KS, Λ, and Λ¯ photoproduction over the ranges 40

1 data table
Table 1

No description provided.


Observation of a Narrow K anti-K State in J/psi Radiative Decays

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 56 (1986) 107, 1986.
Inspire Record 217856 DOI 10.17182/hepdata.20254

Evidence is presented for a narrow state, called ξ, in the decay modes J/ψ→γξ, ξ→K+K−, and ξ→KS0KS0. In the K+K− mode, the ξ has a mass of 2.230±0.006±0.014 GeV/c2, a width of Γ=0.026−0.016+0.020± 0.017 GeV/c2, a product branching ratio of (4.2−1.4+1.7±0.8)×10 −5, and a statistical significance of ∼4.5 standard deviations. In the KS0KS0 mode, it has a mass of 2.232±0.007±0.007 GeV/c2, a width of Γ=0.018−0.015+0.023± 0.010 GeV/c2, a product branching ratio of (3.1−1.3+1.6±0.7)×10 −5, and a statistical significance of ∼3.6 standard deviations. Limits on ξ decay to other final states are presented.

1 data table
Table 1

No description provided.


rivet Analysis
A STUDY OF eta FORMATION IN PHOTON-PHOTON COLLISIONS AT PEP

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Armitage, J.C. ; et al.
Phys.Rev.D 33 (1986) 844, 1986.
Inspire Record 217503 DOI 10.17182/hepdata.23508

The two-photon production of the η meson has been observed, and a value has been determined for the two-photon η decay width by a measurement of the cross section σ(e+e−→e+e−η) where η→γγ. The measurement was made with the TPC/Two-Gamma facility at the SLAC e+e− collider PEP, with an accumulated data sample of 64.5 pb−1. The η→γγ events were both triggered and detected by the pole-tip calorimeter. The measured two-photon η decay width is Γη→γγ=0.64±0.14 (statistical) ±0.13 (systematic) keV, in agreement with earlier similarly determined values.

1 data table
Table 1

No description provided.


rivet Analysis
CHARGED D* MESON PRODUCTION IN e+ e- ANNIHILATION AT S**(1/2) = 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Armitage, J.C. ; et al.
Phys.Rev.D 34 (1986) 1945, 1986.
Inspire Record 217416 DOI 10.17182/hepdata.23509

The production of charmed D* mesons in e+e− annihilations at a center-of-mass energy of 29 GeV has been studied using the time-projection-chamber (TPC) detector at the SLAC storage ring PEP. The production cross section, fragmentation function, and forward-backward asymmetry due to electroweak effects are measured, and a limit on D0-D¯0 mixing is determined.

2 data tables
Table 1

No description provided.

Table 2

No description provided.