Castelli, E.
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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
Table 1

No description provided.


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
Table 1

No description provided.

Table 2

No description provided.


Diffractive Photoproduction of a $b_1 \pi$ System

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 34 (1987) 157, 1987.
Inspire Record 235576 DOI 10.17182/hepdata.15813

None

1 data table
Table 1

Systematic errors are at least 25 pct.


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
Table 1

DIMUON TRIGGER, INELASTIC MEANS Z < 0.9.

Table 2

ELECTRON TRIGGER, INELASTIC MEANS Z < 0.9.


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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Study of a ($D$, $P$) X Reactions at 9-{GeV}/c at Proton Large Transverse Momenta. (In Russian)

Azhgirei, L.S. ; Vzorov, I.K. ; Zhmyrov, V.N. ; et al.
Sov.J.Nucl.Phys. 46 (1987) 661, 1987.
Inspire Record 239398 DOI 10.17182/hepdata.38997

None

1 data table
Table 1

No description provided.


Suppression of Valence Quark Recombination in $\pi^+$ Fragmentation Into $\rho^+$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Belokopytov, Yu.A. ; et al.
Phys.Lett.B 183 (1987) 425, 1987.
Inspire Record 238678 DOI 10.17182/hepdata.30207

We present inclusive ϱ ±,0 and ω cross sections in the beam fragmentation region of π + p interactions at 250 GeV/ c . The near equality of the ϱ + and ϱ 0 cross sections implies suppression of valence quark recombination in forward vector meson production.

1 data table
Table 1

No description provided.


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
Table 1

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.

Table 2

ASSUME A**.75 DEPENDENCE.

Table 3

No description provided.


VERY LOW-ENERGY PION PRODUCTION AT A 300-GeV PROTON BEAM

Bertin, A. ; Capponi, M. ; De Castro, S. ; et al.
CERN-EP/86-196, 1986.
Inspire Record 235590 DOI 10.17182/hepdata.49628

None

2 data tables
Table 1

Data obtained with 30 cm long target.

Table 2

Data from E.Zavattini, Proc. Conf. on Nuclear and Particle Physics at Intermediate Energies with Hadrons, Miramare ( Trieste), 1985, eds. T.Bressani and G.Pauli ( Italian Physical Socirty, Bologna, 1986) p.241. Data obtained with 1.27*1.27*7.62 cm**3 target.


Inclusive $\pi^0$ and Eta0 Production in $\pi^- p$ Interactions at 360-{GeV}/$c$

The NA27 & LEBC-EHS collaborations Aguilar-Benitez, M. ; Bailly, J.L. ; Baland, J.F. ; et al.
Z.Phys.C 34 (1987) 419, 1987.
Inspire Record 234876 DOI 10.17182/hepdata.15777

Theπ0 andη0 production is studied inπ−p interactions at 360 GeV/c. The cross section forπ0 production in the forward hemisphere (X>0) isσ(π0)=(49.7 ± 1.0 ± 1.1) mb and for η withX>0.1,Nch>2,σ(η0)=(3.1 ± 0.5) mb. The ratio of theπ0 toη0 cross section forX>0.1,Nch>2 isσ(π0)/σ(η0). Results on FeynmanX andpT distributions are presented. The data were obtained using the European Hybrid Spectrometer EHS and the bubble chamber LEBC at CERN.

6 data tables
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