New Results From Asp on Single Photon Production at $\sqrt{s}$ 29-{GeV}

Hearty, C. ; Rothberg, J.E. ; Young, K.K. ; et al.
Phys.Rev.Lett. 58 (1987) 1711, 1987.
Inspire Record 244697 DOI 10.17182/hepdata.20171

This Letter reports results of a search for radiative production, by e+e− annihilation of particles that interact only weakly in matter. The search has been made in the total data set of 115 pb−1 acquired with the ASP detector at the SLAC storage ring PEP (s=29 GeV). No anomalous signal was observed. The number of generations of light neutrinos has been limited to Nν<7.5 (90% confidence level). Limits are also placed on the masses of particles predicted to exist by models of supersymmetry.

1 data table

No description provided.


Beauty Production at the CERN Proton - anti-Proton Collider. 1.

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 186 (1987) 237-246, 1987.
Inspire Record 236081 DOI 10.17182/hepdata.30202

We report evidence for beauty particle production through the observation of dimuon events from proton-antiproton collisions at energies of √ s =546 GeV and √ s =630 GeV at the CERN collider. Our data indicate that semi-leptonic decays of beauty particles are the dominant source of pairs of high- p T muons. The beauty flavour creation (gg or q¯q→b¯b ) cross-section needed to explain the dimuon rate is σ{ p¯p→b¯b +X, p b T 5 GeV/c, |η|<2.0}=(1.1±0.1±0.4) μb, which is in good agreement with QCD calculations. We also observe clear signals for ϒ→μ + μ − (hidden beauty) and high- p T J/ψ→μ + μ − , well above the backgraound of continuum muon pairs from the Drell-Yan mechanism.

1 data table

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Limit on the Decay D0 $\to e^\pm \mu^\mp$

Riles, Keith ; Dorfan, J. ; Abrams, G.S. ; et al.
Phys.Rev.D 35 (1987) 2914, 1987.
Inspire Record 236093 DOI 10.17182/hepdata.23380

We have searched for the lepton-flavor-violating decay D0→e±μ∓ in 204 pb−1 of e+e− annihilation data at Ec.m.=29 GeV from the Mark II detector. No candidates were found; we estimate an upper limit on the cross section times branching ratio of σ(e+e−→D0,D¯0; inclusive)B(D0→e±μ∓)<0.35 pb at the 90% confidence level. Simple assumptions yield the rough limit B(D0→e±μ∓)<2.1×10−3. AE.

1 data table

No description provided.


A Study of the Emc Effect Using Neutrino and Anti-neutrino Interactions in Neon and Deuterium

The WA25 & WA59 collaborations Guy, J. ; Saitta, B. ; Apeldoorn, G.Van ; et al.
Z.Phys.C 36 (1987) 337-348, 1987.
Inspire Record 236239 DOI 10.17182/hepdata.15733

Nearly 40000 neutrino and antineutrino interactions in BEBC are compared to measure the differences between neon and deuterium in the quark and antiquark distributions and in the nucleon structure functions. The ratio of Ne to D cross sections indicates some decrease betweenx∼0.2 andx∼0.6. They distributions show there is no significant increase in the neon sea, but prefer a small decrease. Taken altogether, thex andy distributions and the measured total cross-sections indicate some change in the shape of the valence distributions. No significant dependence onA is observed for either the shape of the sea or the ratio of longitudinal to transverse cross-sections.

12 data tables

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Measurements of Total Hadronic and Inclusive $D^*$ Cross-sections in $e^+ e^-$ Annihilations Between 3.87-{GeV} and 4.5-{GeV}

Osterheld, A. ; Hofstadter, R. ; Horisberger, R. ; et al.
SLAC-PUB-4160, 1986.
Inspire Record 238081 DOI 10.17182/hepdata.18759

None

2 data tables

R measurement.

D* cross sections.


The Production of Beauty Particles in $\pi^-$ U Interactions at 320-{GeV} Energy

The WA78 collaboration Catanesi, M.G. ; Muciaccia, M.T. ; Natali, S. ; et al.
Phys.Lett.B 187 (1987) 431-436, 1987.
Inspire Record 235069 DOI 10.17182/hepdata.6522

B B production in π − -uranium interactions has been observed at 320 GeV beam energy looking at events with three muons in the final state. The cross section is found to be σ B B = 4.5±1.4±1.4 nb per nucleon (for a linear A -dependence) or σ B B = 17.6±5.5±5.5 nb per nucleon (assuming A 0.75 dependence). An estimate of x F distribution is given.

3 data tables

BEAUTY INCLUSIVE SPECTRA WAS ASSUMED TO BE E*D(SIG)/D(X)/D(PT**2) = EXP(-0.9*PT**2)*(1-ABS(X))**A. THE BEST FIT FOR A IS A = 2.5.

ASSUME A**.75 DEPENDENCE.

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Inclusive $\pi^0$ Production in $\pi^+ p$, $K^+ p$ and $p p$ Interactions at 250-{GeV}/$c$

The NA22 collaboration Aiinenko, I.V. ; Atayan, M.R. ; Belokopytov, Yu. A. ; et al.
Z.Phys.C 35 (1987) 7, 1987.
Inspire Record 240345 DOI 10.17182/hepdata.40897

Data are presented on inclusive π0 production in the forward c.m. hemisphere (xF>0.025) in π+p,K+p andpp interactions at 250 GeV/c. These data are compared to results at other energies and interpreted in terms of quark-parton models.

4 data tables
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Direct Photon Plus Away - Side Jet Production in $p p$ Collisions at $s^1$/2 = 63-{GeV} and a Determination of the Gluon Distribution

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 34 (1987) 293, 1987.
Inspire Record 235690 DOI 10.17182/hepdata.15800

We have determined the double inclusive cross-section for opposite-side high-pT photons and away-side jets withθγ≈θjet≈90° produced inpp collisions at the CERN Intersecting Storage Rings at\(\sqrt s= 63\) GeV. Under the assumption that these events arise predominantly from the QCD gluon Compton process we have calculated the gluon structure function in the range 0.15≦x≦0.30 at an average square of the four-momentum transfer of 40 GeV2/c2. The data favour a soft gluon distribution in the proton.

2 data tables

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Measurement of $J/\psi$ and $\psi^\prime$ Real Photoproduction on $^{6}$Li at a Mean Energy of 90-{GeV}

The NA14 collaboration Barate, R. ; Bareyre, P. ; Bloch, D. ; et al.
Z.Phys.C 33 (1987) 505, 1987.
Inspire Record 235579 DOI 10.17182/hepdata.15814

Inelastic and elasticJ/ψ (3097) photoproduction on Li6 are measured at a mean γ energy of 90 GeV in an open spectrometer. TheJ/ψ are identified by their decays intoμ+μ− ore+e−. A signal of ψ′(3685) intoμ+μ− andJ/ψπ+π− is also seen. The inelastic cross-section withZ=Eψ/Eγ<0.9 is compared in shape and magnitude with the colour singlet model of photon-gluon fusion.

2 data tables

DIMUON TRIGGER, INELASTIC MEANS Z < 0.9.

ELECTRON TRIGGER, INELASTIC MEANS Z < 0.9.


Observation of Octet and Decuplet Hyperons in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Phys.Lett.B 183 (1987) 419-424, 1987.
Inspire Record 236982 DOI 10.17182/hepdata.30227

Results on hyperon production are reported for data accumulated at 10 GeV centre-of-mass energy with the ARGUS detector. Signals for both the octet states Λ, Σ 0 and Ξ − and the decuplet states Σ ± (1385), Ξ 0 (1530) and Ω − are observed 1 (references to a specific state are to be interpreted as also implying the charge conjugate state), some for the first time in e + e − annihilation. Baryon rates from γ dir (1S) decays are enhanced by a factor of about 3 over the continuum.

2 data tables

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