Date

Charged Meson Pair Production in $\gamma \gamma$ Interactions

Boyer, J. ; Burke, D.L. ; Butler, F. ; et al.
Phys.Rev.Lett. 56 (1986) 207, 1986.
Inspire Record 220003 DOI 10.17182/hepdata.20236

The cross section for the production of π+π− or K+K− pairs in γγ interactions is measured for mππ between 1.7 and 3.5 GeV/c2 and for two intervals of γγ center-of-mass scattering angle. Results are compared with predictions of a QCD model.

2 data tables

Data read off graph.

Data read off graph.


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

No description provided.


Measurement of the $K^0^*$ (896) Radiative Width

Carlsmith, D. ; Bernstein, R.H. ; Bock, G.J. ; et al.
Phys.Rev.Lett. 56 (1986) 18, 1986.
Inspire Record 217703 DOI 10.17182/hepdata.20252

Primakoff production of the K0*(896) by incident KL’s was observed in the energy range 100–200 GeV. Production from Cu and Pb targets was measured simultaneously leading to a new value for the K0*(896) radiative width Γ(K0*(896)→K0+γ) of 116.5±9.9 keV. The result agrees with a previous determination while being considerably more precise and allows for more stringent tests of quark-model relations among the radiative widths of the low-lying vector mesons.

1 data table

Data requested from authors.


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

No description provided.


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

No description provided.


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

No description provided.

No description provided.


Upper Limits of the Proton Magnetic Form-factor in the Timelike Region From $\bar{p} p \to e^+ e^-$ at the {CERN} {ISR}

The Annecy(LAPP)-CERN-Genoa-Lyon-Oslo-Rome-Strasbourg-Turin collaboration Baglin, C. ; Baird, S. ; Bassompierre, G. ; et al.
Phys.Lett.B 163 (1985) 400-403, 1985.
Inspire Record 218159 DOI 10.17182/hepdata.49639

From the measurement of e + e - pairs from the reaction p̄p→e + e - at the CERN-ISR, using an antiproton beam and a hydrogen jet target, we derived upper limits for the proton magnetic form factor in the time-like region at Q 2 ⋍8.9( GeV c ) 2 and Q 2 ⋍12.5( GeV c ) 2 .

1 data table

No description provided.


Measurement of W+- and Z0 Properties at the CERN anti-p p Collider

The UA2 collaboration Appel, J.A. ; Bagnaia, P. ; Banner, M. ; et al.
Z.Phys.C 30 (1986) 1, 1986.
Inspire Record 218462 DOI 10.17182/hepdata.2113

A study ofW± andZ0 properties has been performed using the UA2 detector at the\(\bar pp\) collider. The data correspond to a total integrated luminosity of 142 nb−1 at\(\sqrt s \)=546 GeV, and of 310 nb−1 at\(\sqrt s \)=630 GeV. The experimental results are compared with the predictions of the Standard Model of the unified electroweak theory.

3 data tables

No description provided.

No description provided.

No description provided.


INCLUSIVE PRODUCTION OF THE DELTA (1232) RESONANCE IN MUON - PROTON SCATTERING AT 280-GeV/c

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Nucl.Phys.B 264 (1986) 739-751, 1986.
Inspire Record 218464 DOI 10.17182/hepdata.33712

Inclusive production of the Δ (1232) resonance has been measured in 280 GeV/ c muon-proton interactions. The production of the Δ ++ as a function of the variables χ BJ , W , Q 2 , χ F and p T 2 is investigated. The average Δ ++ multiplicity is found to be smaller, by a factor of 6.2 ± 1.2, than the average multiplicity of protons. An upper limit for Δ 0 production is obtained. The net hadronic charge distribution for events with a Δ ++ is presented. The results are compared to the predictions of the Lund and Fire string models.

2 data tables

No description provided.

No description provided.


Comparison of Charged Particle Multiplicities in Quark and Gluon Jets Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 165 (1985) 449-453, 1985.
Inspire Record 17442 DOI 10.17182/hepdata.30286

The charged particle multiplicities of the quark and gluon jets in the three-fold symmetric e + e − → q q g events at √ s = 29 GeV have been studied using the high resolution spectrometer at PEP. A value of 〈 n 〉 g = 6.7 −2.1 +1.1 ±1.0 for gluon jet s with an energy of 9.7 −2.0 +1.5 GeV is measured. The ratio, 〈 n 〉 g /〈 n 〉 q , is 1.29 −0.41 +0.21 ±0.20, which i s significantly lower than the value of 9 4 naively expected from the ration of the gluon-to-quark color charges.

1 data table

Mean jet charged particle interpretations for gluon and quark jets as described above.