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Studies of Intermediate Vector Boson Production and Decay in {UA1} at the {CERN} Proton - Antiproton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 44 (1989) 15-61, 1989.
Inspire Record 267170 DOI 10.17182/hepdata.15015

An extensive study of production and decay properties of charged and neutral Intermediate Vector Bosons (IVB) at the CERN proton-antiproton collider is presented. Intermediate Vector Bosons were detected in the electron, muon, and tau decay modes at centre-of-mass energies of 0.546 and 0.630 TeV. This paper is a summary, based on all the available data from the UA1 experiment from the running periods 1982–1985. Results are presented and compared with expectations of the Standard Eletroweak Model and QCD-improved Drell-Yan annihilation processes. The general conclusion is that there is an excellent agreement between the predictions of the Standard Model and our measurements.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Observation of the Charmed Strange Baryon $\Xi(c$)0

The CLEO collaboration Avery, P. ; Besson, D. ; Garren, L. ; et al.
Phys.Rev.Lett. 62 (1989) 863, 1989.
Inspire Record 267892 DOI 10.17182/hepdata.20029

We present evidence from the CLEO detector for the charmed strange baryon Ξc0. It is seen in nonresonant e+e− annihilations at s of 10.5 GeV through its decay to Ξ−π+. The measured Ξc0 mass is 2471 ± 3 ± 4 MeV/c2.

1 data table
Table 1

Production cross section times branching fraction for the sum of both particle and antiparticle. Error contains both statistics and systematics. X is defined as SQRT(P(P=3)**2/(EBEAM**2-M(P=3)**2)).


A Measurement of W Boson Production in 1.8-TeV anti-p p Collisions

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 62 (1989) 1005, 1989.
Inspire Record 267998 DOI 10.17182/hepdata.20078

The cross section for the production and subsequent decay to electron and neutrino of the W intermediate vector boson has been measured in 1.8-TeV p¯p collisions at the Fermilab Tevatron Collider. An analysis of events with missing transverse energy greater than 25 GeV and with an electron of transverse energy greater than 15 GeV from a datum sample of 25.3 nb−1 gives σB=2.6±0.6±0.5 nb.

1 data table
Table 1

Branching ratio to electron and neutrino.


Measurement of the Inclusive Jet Cross-Section in anti-p p Collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 62 (1989) 613, 1989.
Inspire Record 267999 DOI 10.17182/hepdata.20032

Inclusive jet production at s=1.8 TeV has been measured in the CDF detector at the Fermilab Tevatron p¯p Collider. Jets with transverse energies (Et) up to 250 GeV have been observed. The Et dependence of the inclusive jet cross section is consistent with leading-order quantum-chromodynamic calculations, and comparison with lower-energy data shows deviations from scaling consistent with QCD. A lower limit of 700 GeV (95% confidence level) is placed on the quark compositeness scale parameter Λc associated with an effective contact interaction.

1 data table
Table 1

No description provided.


MEASUREMENTS OF THE e+ e- TOTAL HADRONIC CROSS-SECTION AND A DETERMINATION OF M(Z) AND LAMBDA (MS)

The AMY collaboration Mori, T. ; Nozaki, T. ; Blanis, D. ; et al.
Phys.Lett.B 218 (1989) 499-507, 1989.
Inspire Record 276653 DOI 10.17182/hepdata.29847

The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .

1 data table
Table 1

No description provided.


Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.
Phys.Rev.Lett. 62 (1989) 1713, 1989.
Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


K0(S) PRODUCTION IN ANTI-P P INTERACTIONS AT S**(1/2) = 630-GeV AND 1800-GEV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.D 40 (1989) 3791-3794, 1989.
Inspire Record 287811 DOI 10.17182/hepdata.22999

Measurements of inclusive transverse-momentum spectra for KS0 mesons produced in proton-antiproton collisions at s of 630 and 1800 GeV are presented and compared with data taken at lower energies. The ratio, as a function of pT, of the cross section for KS0 to that for charged hadrons is very similar to what is observed at lower energies. At 1800 GeV, we calculate the strangeness-suppression factor λ=0.40±0.05.

4 data tables
Table 1

Estimated effective cross sections for events which pass the trigger and selection criteria. The uncertainties in these represent the principal source of error in the overall normalisation of the results.

Table 2

Statistical errors only.

Table 3

Statistical errors only.

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The Production of $J/_{\psi}$ and Associated Particles in the Collision of 530 GeV/c Protons and Pions with Nuclear Targets

De, K. ; Crittenden, R. ; Dzierba, A. ; et al.
(1989) 467-472, 1989.
Inspire Record 280605 DOI 10.17182/hepdata.22998

None

3 data tables
Table 1

Interacting beam cross-section.

Table 2

No description provided.

Table 3

No description provided.


Dijet Angular Distributions from anti-p p Collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 62 (1989) 3020-3023, 1989.
Inspire Record 278394 DOI 10.17182/hepdata.20046

We have measured dijet angular distributions at √s =1.8 TeV with the Collider Detector at Fermilab and the Tevatron p¯p Collider and find agreement with leading-order QCD. By comparing the distribution for the highest dijet invariant masses with the prediction of a model of quark compositeness, we set a lower limit on the associated scale parameter Λc at 330 GeV (95% C.L.).

1 data table
Table 1

Numerical values read from figure in preprint.


Studies of Jet Production Rates in $e^+ e^-$ Annihilation at $e$({CM}) = 29-{GeV}

Bethke, S. ; Abrams, G. ; Adolphsen, C.E. ; et al.
Z.Phys.C 43 (1989) 325, 1989.
Inspire Record 277772 DOI 10.17182/hepdata.15472

Production rates of multijet hadronic final states are studied ine+e− annihilation at 29 GeV center of mass energy. QCD shower model calculations with exact first order matrix element weighting at the first gluon vertex are capable of reproducing the observed multijet event rates over a large range of jet pair masses. The method used to reconstruct jets is well suited for directly comparing experimental jet rates with parton rates calculated in perturbative QCD. Evidence for the energy dependene of αs is obtained by comparing the observed production rates of 3-jet events with results of similar studies performed at higher center of mass energies.

2 data tables
Table 1

Observed production rates relative to the total hadronic cross section.

Table 2

Production rates corrected for fragmentation, initial state radiation and detector effects.