HEPData Search

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A Study of the recombination scheme dependence of jet production rates and of alpha-s (m(Z0)) in hadronic Z0 decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.

Z.Phys.C 49 (1991) 375-384, 1991.

Inspire Record 299833 DOI 10.17182/hepdata.15085

The error includes the experimental uncertainties (±0.003), uncertainties of hadronisation corrections and of the degree of parton virtualities to which the data are corrected, as well as the uncertainty of choosing the renormalisation scale.

9 data tables

Table 1

Jet production rates using the E0 recombination scheme.

Table 2

Jet production rates using the E recombination scheme.

Table 3

Jet production rates using the p0 recombination scheme.

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Beauty production at the CERN p anti-p collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.

Phys.Lett.B 256 (1991) 121-128, 1991.

Inspire Record 302583 DOI 10.17182/hepdata.48531

We report measurements of b-quark and B-hadron production in pp̄ collisions at √ s =630 GeV. We use muon samples to extract beauty production cross-sections over a wide range of transverse momentum in the central rapidity range | y | < 1.5. We compare our results to an O(α s 3 ) QCD prediction and find good agreement over the measured b-quark transverse momentum range 6 GeV / c to 54 GeV / c . Using the shape of the p T and y distribution predicted by QCD to extrapolate our data, we infer a total cross-section for b-quark production at √s=630 GeV of σ( p p ̄ → b b ̄ + X )=19.3±7( exp. )±9( th. μ b .

10 data tables

Table 1

No description provided.

Table 2

The cross section is multipled on the B(J/PSI --> MU+ MU-).

Table 3

No description provided.

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The Reaction pomeron-pomeron ---> pi+ pi- and an unusual production mechanism for the f2 (1270)

The Ames-Bologna-CERN-Dortmund-Heidelberg-Warsaw collaboration Breakstone, A. ; Campanini, R. ; Crawley, H.B. ; et al.

Z.Phys.C 48 (1990) 569-576, 1990.

Inspire Record 28759 DOI 10.17182/hepdata.15080

Data are presented on Pomeron-Pomeron interactions which produce a centralπ+π− system in proton-proton collisions at\(\sqrt s= 62 GeV\) at the CERN Intersecting Storage Rings. This process may favor the production of gluonic bound states. A partial-wave analysis of theπ+π− system shows evidence for the production of the statesf0(975),f0(1400), andf2(1270). The fitted mass for thef2(1270) is about 50 MeV below the world average. In addition, the production mechanism for thef2(1270) is uniquely different from that for the other final states in that there is a correlation between the outgoing protons. this is consistent with a picture of two-gluon exchange with thef2(1270) produced by gluon fusion, and could indicate that thef2(1270) has a glueball component.

1 data table

Table 1

No description provided.

Rapidity and transverse momentum structure in pi+ and K+ collisions with Al and Au nuclei at 250-GeV/c

The EHS/NA22 collaboration Agababyan, N.M. ; Ajinenko, I.V. ; Belokopytov, Yu. A. ; et al.

Z.Phys.C 50 (1991) 361-372, 1991.

Inspire Record 302020 DOI 10.17182/hepdata.14979

An analysis is presented of the rapidity and transverse momentum distributions and of the nuclear stopping power in collisions ofπ+ andK+ mesons with Al and Au nuclei at 250 GeV/c. The experimental results are compared to predictions of the additive quark model and the dual parton model. The AQM offers an overall consistent description of the data in this experiment. The DPM reproduces reasonably well the rapidity spectra in the central and projectile fragmentation regions, but fails to describe the nuclear stopping power.

14 data tables

Table 1

No description provided.

Table 2

Excluding protons of PLAB < 1.2 GeV.

Table 3

No description provided.

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A Search for substructure of leptons and quarks with the CELLO detector

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Field, J.H. ; et al.

Z.Phys.C 51 (1991) 149-156, 1991.

Inspire Record 301727 DOI 10.17182/hepdata.14981

Differential cross section data of the CELLO experiment on pair production of muons, taus, and heavy quarks ine+e−-annihilation are presented and analysed, together with our data on Bhabha scattering, in terms of compositeness effects characterized by the mass scale Λ. We discuss difficulties in the combination of limits Λ from different experiments. The appropriate parameter to combine different results turns out to be ɛ=±1/Λ2, which is in contrast to Λ Gaussian distributed.

10 data tables

Table 1

Errors are combined statistics and systematics.

Table 2

Errors are combined statistics and systematics.

Table 3

Errors are combined statistics and systematics.

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Charged pion production in noninclusive proton - nucleus interactions at .8-GeV and 1.6-GeV incident energies

Lemaire, M.C. ; Trzaska, M. ; Alard, J.P. ; et al.

Phys.Rev.C 43 (1991) 2711-2721, 1991.

Inspire Record 304286 DOI 10.17182/hepdata.26174

Charged pions and light nuclei (p, d, t, He3, and He4) have been measured in the interaction of proton beams with C, Nb, and Pb targets at 0.8 and 1.6 GeV incident energies, using a large solid angle detector. From slices on the multiplicity of protonlike particles (free protons and protons bound in light fragments), the events have been sorted out into two classes corresponding to more peripheral and more central collisions. For each class of events, the mean value and the dispersion of the π+ and π− multiplicity distributions have been studied as a function of target mass and incident energy. Comparisons to the Liege intranuclear cascade predictions exhibit some discrepancies which are discussed.

7 data tables

Table 1

OBSERVATION OF THE PROTONLIKE MULTIPLICITY.

Table 2

OBSERVATION OF PERCENTAGE OF THE PROTONLIKE MULTIPLICITY REACTIONS.

Table 3

OBSERVATION OF PERCENTAGE OF THE PROTONLIKE MULTIPLICITY REACTIONS.