Morris, W.
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Measurement of the $\bar{p} p \to \bar{n} n$ Cross-section at Low $\bar{p}$ Momenta

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 169 (1986) 302-308, 1986.
Inspire Record 219986 DOI 10.17182/hepdata.30264

First measurements of the differential cross section are presented for p ̄ p → n ̄ n at LEAR in the momentum range between 180 and 600 MeV/ c . The differential cross sections show a forward peaking followed by a smooth drop-off. No indication of the “bump-dip” structure reported at higher momenta has been observed. The angle-integrated charge-exchange cross sections are determined down to E n ̄ n cm = 6.6 MeV .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Scaling Violations in Multiplicity Distributions at 200-GeV and 900-GeV

The UA5 collaboration Alner, G.J. ; Ansorge, R.E. ; Asman, B. ; et al.
Phys.Lett.B 167 (1986) 476-480, 1986.
Inspire Record 220002 DOI 10.17182/hepdata.30284

New data are presented on charged particle multiplicity distributions for non single-diffractive events produced at CM energies s = 200 and 900 GeV . The data were obtained at the CERN antiproton-proton collider operated in a new pulsed mode. The multiplicity distributions are very well described by a negative binomial distribution. The highest energy data show no sign of approaching scaling, confirming our earlier results on the breaking of KNO scaling. The energy variation of the average charged multiplicity can be fitted to a quadratic in ln s or a s 0.13 dependence.

3 data tables
Table 1

Figure gives uncorrected multiplicity distributions. Here we give the corrected distributions. Data supplied by D. Ward.

Table 2

Results for multiplicity moments based on negative binomial fit to corrected data. Errors reflect both statistical and systematic effects. Results from earlier data at 546 Gev cm energy are also given.

Table 3

C moments for corrected data where CQ=<N**Q>/<N>**Q.


Direct Measurements of Charmed d Meson Hadronic Branching Fractions

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 56 (1986) 2140, 1986.
Inspire Record 220653 DOI 10.17182/hepdata.20248

A new technique is applied to data collected at the ψ(3770) resonance to derive charmed-D-meson branching fractions without relying on the measurement of D-production cross sections. Measurements are presented for three decay modes of the D0 (K−π+, D−π−π+π+, and K−π+π0 and four decay modes of the D+ (K−π+π+,K−π+π+π0,KS0π+, and KS0π+π0). The resulting branching fractions are significantly larger than previous measurements.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Intermediate Vector Boson Properties at the {CERN} Super Proton Synchrotron Collider

The UA1 collaboration Arnison, G. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
EPL 1 (1986) 327-345, 1986.
Inspire Record 219230 DOI 10.17182/hepdata.30283

The properties of a sample of 172 charged intermediate vector bosons decaying in the (eνe) channel and 16 neutral intermediate vector bosons decaying in the (e+e-) channel are described. Masses, decay widths, decay angular distributions, and production cross-sections are given; they are shown to be in excellent agreement with the expectations of the SU2 ⊗ U1 standard model. A limit is put on the number of light-neutrino types Nν ≤ 10 at 90% c.l.

2 data tables
Table 1

W CROSS SECTIONS ARE GIVEN IN ARNISON ET AL., NC 44A, 1.

Table 2

No description provided.


Observation of a New Charmed Meson.

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Rev.Lett. 56 (1986) 549, 1986.
Inspire Record 222219 DOI 10.17182/hepdata.20225

Using the ARGUS detector at the DORIS II e+e− storage ring at DESY, we have obtained evidence for a new charmed resonance which decays into D*±(2010)π∓. The observed mass and width are 2420±6 MeV/c2 and 70±21 MeV/c2, respectively. The fragmentation function is found to be hard, as expected for a state containing a leading charm quark produced by nonresonant e+e− annihilation.

2 data tables
Table 1

No description provided.

Table 2

Estimated production cross section obtained by comparison with observed D*(2010) production rate.


Tests of the Standard Model in Leptonic Reactions at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Z.Phys.C 30 (1986) 371, 1986.
Inspire Record 222566 DOI 10.17182/hepdata.48419

An analysis of the three leptonic reactionse+e−→e+e−,μ+μ− andτ+τ− over a wide range of energy,\(12< \sqrt s< 46.78 GeV\) is presented. The data were obtained with the JADE detector at thee+e− storage ring PETRA. They are compared to predictions of electroweak theories, in particular the standard model. For the total cross-sections of all three reactions and for the differential cross-section of Bhabha scattering no deviation from QED is found over the entire energy range. The differential cross-sections of μ and τ pairs at high energies show the angular asymmetry predicted by electroweak interference. The axial-vector and vector weak coupling constant, sin2θW andMZ are determined and compared to other measurements. Finally, limits on deviations from the standard model are given.

36 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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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Inclusive Photoproduction of $\phi$, $K^*$ (890) and $K^*$ (1420) in the Photon Energy Range 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 30 (1986) 521, 1986.
Inspire Record 218609 DOI 10.17182/hepdata.15900

Inclusive photoproduction of ϕ,K*0(890),\(\bar K*^0 \) andK*0(1420),\(\bar K*^0 \) has been studied in γp collisions with photons of energy 20 to 70 GeV and in the range 0.1≦xF≦0.95 [0.4≦xF≦0.8 for the\(\mathop K\limits^{( - )} *\)(1420)],xF being the Feynman variable of the vector/tensor meson. The cross-sections for these processes, averaged over the photon energy range and integrated overxF are given. The inclusive ϕ production in the forward direction can be described quantitatively by a triple-Regge model calculation. The remaining ϕ production and the totalK*0(890) and\(\bar K*^0 \) production are consistent with a quark fusion picture.

1 data table
Table 1

No description provided.


Observation of Three 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Longacre, R.S. ; et al.
Phys.Lett.B 165 (1985) 217-221, 1985.
Inspire Record 218668 DOI 10.17182/hepdata.30309

We present data on 3652 analyzed events of the reaction π - p → φφn at 22 GeV/ c . A partial wave analysis has been performed on the φφ system. The results are well represented by three resonances all with quantum numbers I G J PC = 0 + 2 ++ . The absence of the Okubo-Zweig-Iizuka suppression observed in this reaction, the selection of only three J PC =2 ++ states ( g T , g T′ , and g T ″ ) which comprise virtually all of the cross section, and the large φφn signal over a very different φK + K - n background are all well explained if these states are produced by 1–3 glueballs (i.e. multigluon resonances).

1 data table
Table 1

Slope indicates pion exchange process.


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
Table 1

No description provided.

Table 2

No description provided.