Battiston, R.
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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.


rivet Analysis
Scaling of Pseudorapidity Distributions at c.m. Energies Up to 0.9-TeV

The UA5 collaboration Alner, G.J. ; Ansorge, R.E. ; Asman, B. ; et al.
Z.Phys.C 33 (1986) 1-6, 1986.
Inspire Record 233599 DOI 10.17182/hepdata.15816

New data are presented on charged particle pseudorapidity distributions for inelastic events produced at c.m. energies\(\sqrt s \)=200 and 900 GeV. The data were obtained at the CERN antiproton-proton Collider operated in a new pulsed mode. The rise of the central density ρ(0) at energies up to\(\sqrt s \)=900 GeV has been studied. A new form of central region scaling is found involving the densityρn(0) for charged multiplicityn, namely that the scaled central densityρn(0)/ρ(0) expressed as a function ofz=n/〈n〉 is independent ofs. Scaling in the fragmentation region holds to 10–20%, and the small amount of scalebreaking observed here could be accommodated within the framework suggested by Wdowcyk and Wolfendale to account for both accelerator and cosmic ray data.

4 data tables
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Angular Distributions for High Mass Jet Pairs and a Limit on the Energy Scale of Compositeness for Quarks from the CERN p anti-p Collider

The UA1 collaboration Arnison, G. ; Albajar, C. ; Albrow, M.G. ; et al.
Phys.Lett.B 177 (1986) 244-250, 1986.
Inspire Record 230633 DOI 10.17182/hepdata.30248

Angular distributions of high-mass jet pairs (180< m 2 J <350 GeV) have been measured in the UA1 experiment at the CERN pp̄ Collider ( s =630 GeV ) . We show that angular distributions are independent of the subprocess centre-of-mass (CM) energy over this range, and use the data to put constraints on the definition of the Q 2 scale. The distribution for the very high mass jet pairs (240< m 2 J <300 GeV) has also been used to obtain a lower limit on the energy scale Λ c of compositeness of quarks. We find Λ c >415 GeV at 95% confidence level.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Diffraction Dissociation at the {CERN} Pulsed Collider at {CM} Energies of 900-{GeV} and 200-{GeV}

The UA5 collaboration Ansorge, R.E. ; Åsman, B. ; Booth, C.N. ; et al.
Z.Phys.C 33 (1986) 175, 1986.
Inspire Record 232615 DOI 10.17182/hepdata.15812

Cross-sections for diffractive particle production and pseudorapidity distributions of the decay products of diffractive states are presented. The data were obtained with the UA 5 streamer chamber detector at the CERNpp Collider operated in a new pulsed mode yieldingpp interactions at c.m. energies of 900 and 200 GeV. Data recorded with a special trigger designed to select a sample of events enriched in single-diffractive interactions clearly favour apt-limited fragmentation of diffractive states. The cross-section for single-diffractive particle production ϊ was found to be 7.8±0.5±1.1 mb at 900 GeV and 4.8±0.5±0.8 mb at 200 GeV (first error statistical, second systematic). From the pseudorapidity distribution of diffractive states we deduce the average number of charged particles to be 6.5±1.0 at 900 GeV and 4.1±1.1 at 200 GeV. Furthermore we report on our estimates for the cross-section of double-diffractive particle production at both Collider energies.

3 data tables
Table 1

Single diffractive cross sections.

Table 2

Average number of single diffractive charged particles.

Table 3

Estimate of the double diffractive cross sections.


Direct Photon Production at the {CERN} $\bar{p} p$ Collider

The UA2 collaboration Appel, J.A. ; Bagnaia, P. ; Banner, M. ; et al.
Phys.Lett.B 176 (1986) 239, 1986.
Inspire Record 229895 DOI 10.17182/hepdata.30247

Using the UA2 apparatus, the inclusive cross section has been measured for production of high- p T direct photons in p̄p collisions at s =546 GeV and s =630 GeV . The results are in good agreement with QCD predictions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Antiproton-proton cross sections at 200 and 900 {GeV} c.m. energy

The UA5 collaboration Alner, G.J. ; Ansorge, R.E. ; Asman, B. ; et al.
Z.Phys.C 32 (1986) 153-161, 1986.
Inspire Record 229896 DOI 10.17182/hepdata.15857

Data on antiproton-proton cross sections at the c.m. energies 200 and 900 GeV are presented. The data were obtained at the CERN antiproton-proton Collider operated in a new pulsed mode in which the same beams were accelerated and decelerated between beam energies of 450 and 100 GeV. The properties of the machine determine the ratio of the luminosities at the two energies to about 1% and thus an accurate measurement of the ratioR of the inelastic cross sections could be made. We findR (=σ900/σ200)=1.20±0.01±0.02, where the first error is statistical and the second systematic. Interpolating existing data to estimateσine1(200 GeV) this measurement ofR leads toσine1(900 GeV)=50.3+0.4+1.0 mb. Using an extrapolated value ofσe1/σtot we estimate the total cross section at 900 GeV to be 65.3±0.7±1.5 mb. Both the inelastic and total cross sections are compatible with a ln2s dependence. Comparisons are made with different fits to the total cross section energy dependence.

2 data tables
Table 1

Ratio of inelastic cross sections at 900 and 200 Gev.

Table 2

Estimate of 900 Gev total cross section based on a) interpolation to obtain total cross section at sqrt(s)=200 Gev (51.6 +- 0.4mb.) b) interpolation and extrapolation to obtain the ratio of elastic to total cross sections at 200 & 900 Gev (0.19 +- 0.01 and 0.23 +- 0.01 respectively).


Large T Elastic Scattering at the {CERN} {SPS} Collider at $\sqrt{s}=630$-{GeV}

The UA4 collaboration Bernard, Denis ; Bozzo, M. ; Braccini, P.L. ; et al.
Phys.Lett.B 171 (1986) 142-144, 1986.
Inspire Record 227143 DOI 10.17182/hepdata.30263

Proton-antiproton elastic scattering was measured at the centre-of-mass energy s = 630 GeV in the four-momentum transfer range 0.7 ⩽ − t ⩽ 2.2 GeV 2 . The new data confirm our previous results at s = 546 GeV on the presence of a break in the t -distribution at − t ≃ 0.9 GeV 2 which is followed by a shoulder, and extend the momentum transfer range to larger values. The t -dependence of the differential cross section beyond the break is discussed.

1 data table
Table 1

Errors contain statistics and acceptance uncertainty.


Measurement of the Inclusive Jet Cross-Section at the CERN p anti-p Collider

The UA1 collaboration Arnison, G. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 172 (1986) 461-466, 1986.
Inspire Record 228112 DOI 10.17182/hepdata.30262

The inclusive jet cross section has been measured in the UA1 experiment at the CERN p p Collider at centre-of-mass energies √ s = 546 GeV and √ s = 630 eV. The cross sections are found to be consistent with QCD predictions, The observed change in the cross section with the centre-of-mass energy √ s is accounted for in terms of x T scaling.

1 data table
Table 1

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.


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.