Thomas, D.L.
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A Measurement of jet shapes in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Anway, Carol E. ; et al.
Phys.Rev.Lett. 70 (1993) 713-717, 1993.
Inspire Record 340125 DOI 10.17182/hepdata.19744

We present a measurement of jet shapes in p¯p collisions at √s =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab (CDF). Qualitative agreement is seen with the predictions of recent next-to-leading [O(αs3)] calculations and with leading logarithm QCD based Monte Carlo simulations. The dependence of the jet shape on transverse energy is studied.

1 data table
Table 1

No description provided.


Measurement of the production rates of eta and eta-prime in hadronic Z decays

The ALEPH collaboration Buskulic, D. ; Decamp, D. ; Goy, C. ; et al.
Phys.Lett.B 292 (1992) 210-220, 1992.
Inspire Record 334575 DOI 10.17182/hepdata.29156

The decays η → γγ and η ′ → ηπ + π − have been observed in hadronic decays of the Z produced at LEP. The fragmentation functions of both the η and η ′ have been measured. The measured multiplicities for x > 0.1 are 0.298±0.023±0.021 and 0.068±0.016 for η and η ′ respectively. While the fragmentation function for the η is fairly well described by the JETSET Monte Carlo, it is found that the production rate of the η ′ is a factor of four less than the corresponding prediction.

3 data tables
Table 1

No description provided.

Table 2

Additional 7 pct systematic error.

Table 3

Additional 23 pct systematic error.


Properties of hadronic Z decays and test of QCD generators

The ALEPH collaboration Buskulic, D. ; Decamp, D. ; Goy, C. ; et al.
Z.Phys.C 55 (1992) 209-234, 1992.
Inspire Record 334577 DOI 10.17182/hepdata.1420

Distributions are presented of event shape variables, jet roduction rates and charged particle momenta obtained from 53 000 hadronicZ decays. They are compared to the predictions of the QCD+hadronization models JETSET, ARIADNE and HERWIG, and are used to optimize several model parameters. The JETSET and ARIADNE coherent parton shower (PS) models with running αs and string fragmentation yield the best description of the data. The HERWIG parton shower model with cluster fragmentation fits the data less well. The data are in better agreement with JETSET PS than with JETSETO(αS2) matrix elements (ME) even when the renormalization scale is optimized.

41 data tables
Table 1

Sphericity distribution.

Table 2

Sphericity distribution.

Table 3

Aplanarity distribution.

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A Measurement of the production and muonic decay rate of W and Z bosons in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 69 (1992) 28-32, 1992.
Inspire Record 334085 DOI 10.17182/hepdata.19817

An analysis of proton-antiproton collisions at √s =1.8 TeV recorded with the Collider Detector at Fermilab (CDF) yields σ(pp¯→WX)B(W→μν)=2.21±0.22 nb and σ(pp¯→ZX)B(Z →μ+μ−)=0.226±0.032 nb. The ratio is Rμ=σWB(W→μν)/σZB(Z→μ+μ−)=9.8±1.2. Combining with previous CDF electron results gives σWB(W→lν)=2.20±0.20 nb, σZB(Z→l+l−)=0.214±0.023 nb, and Rl=10.0±0.8. We extract the ratios of the coupling constants gμ/ge and gτ/gμ. Using standard model assumptions we deduce the inverse branching ratio B−1(W→lν), the width Γ(W), and a decay-mode-independent lower bound on the top quark mass of 45 GeV/c2 (95% C.L.).

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Global determination of alpha-s (M(z0)) at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 55 (1992) 1-24, 1992.
Inspire Record 333079 DOI 10.17182/hepdata.14606

The value of the strong coupling constant,$$\alpha _s (M_{Z^0 } )$$, is determined from a study of 15 d

16 data tables
Table 1

Differential jet mass distribution for the heavier jet using method T. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

Table 2

Differential jet mass distribution for the jet mass difference using methodT. The data are corrected for the finite acceptance and resolution of the detec tor and for initial state photon radiation.

Table 3

Differential jet mass distribution for the heavier jet using method M. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

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Measurement of the isolated prompt photon cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 68 (1992) 2734-2738, 1992.
Inspire Record 333081 DOI 10.17182/hepdata.19869

We present a measurement of the cross section for production of isolated prompt photons in p¯p collisions at √s =1.8 TeV. The cross section, measured as a function of transverse momentum (PT), agrees qualitatively with QCD calculations but has a steeper slope at low PT.

1 data table
Table 1

Additional normalization systematic uncertainty of 27 pct for first eleven entries, and +32 pct(-46 pct) for last four entries.


Evidence for the triple gluon vertex from measurements of the QCD color factors in Z decay into four jets

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Phys.Lett.B 284 (1992) 151-162, 1992.
Inspire Record 333127 DOI 10.17182/hepdata.48505

None

1 data table
Table 1

NC, CF, and TF are the color factors for SU(N) group. For SU(3) they are equal to: NC = 3, CF = 4/3, and TF = 1/2.


Evidence for b flavored baryon production in Z0 decays at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 281 (1992) 394-404, 1992.
Inspire Record 333300 DOI 10.17182/hepdata.48511

We observe evidence for the production of b-flavoured baryons in decays of the Z 0 boson with the OPAL detector at LEP. We find 68 Λl − , Λ l + candidates in 458 583 hadronic Z 0 decays. We interpret this as a signal of 55 ± 9 +0.3 −3.1 events from the semi-leptonic decays of b baryons. Assuming weakly decaying b baryons produced in Z 0 decays are mostly Λ b particles, we measure the product branching ratio (Γ b b /Γ had ) f ( b →Λ b ) B (Λ b →Λl − v X ) , averaged over the electron and muon channels, to be (6.2±1.0±1.5)×10 −4 .

1 data table
Table 1

FD is considered as a quark fragmentation fraction. Charge conjugated state is understood.


Measurement of alpha-s in hadronic Z decays using all orders resummed predictions

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Phys.Lett.B 284 (1992) 163-176, 1992.
Inspire Record 333334 DOI 10.17182/hepdata.48421

None

1 data table
Table 1

Three different methods are used for extraction Alphas value (see text for details). Systematical errors with C=HADR and C=THEOR are due to hadronization correction and theoretical uncertainties.


n p elastic spin transfer measurements at 485-MeV and 635-MeV

McNaughton, K.H. ; Ambrose, D.A. ; Coffey, P. ; et al.
Phys.Rev.C 46 (1992) 47-51, 1992.
Inspire Record 342389 DOI 10.17182/hepdata.26097

We have measured the spin-transfer parameters KLL, KSL, KLS, and KSS at 635 MeV from 50° to 178° c.m. and at 485 MeV from 74° to 176° c.m. These new data have a significant impact on the phase-shift analyses. There are now sufficient data near these energies to overdetermine the elastic nucleon-nucleon amplitudes.

2 data tables
Table 1

Spin transfer parameters from np elastic scattering at 635 MeV. There is an additional overall normalisation of 2 PCT.

Table 2

Spin transfer parameters from np elastic scattering at 485 MeV. There is an additional overall normalisation of 2 PCT.