Beddo, M.
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Measurements of the electric and magnetic form-factors of the proton from Q**2 = 1.75-GeV/c**2 to 8.83-GeV/c**2

Bosted, Peter E. ; Clogher, L. ; Lung, A. ; et al.
Phys.Rev.Lett. 68 (1992) 3841-3844, 1992.
Inspire Record 332962 DOI 10.17182/hepdata.19849

The proton elastic electric and magnetic form factors, GEp(Q2) and GMp(Q2), have been separately measured in the range Q2=1.75 to 8.83 (GeV/c)2, more than doubling the Q2 range of previous data. Scaled by the dipole fit, GD(Q2), the results for GMp(Q2)/μpGD(Q2) decrease smoothly from 1.05 to 0.91, while GEp(Q2)/GD(Q2) is consistent with unity. Comparisons are made to QCD sum rule, diquark, constitutent quark, and vector meson dominance models, none of which agree with all of the new data. The ratio Q2F2/F1 approaches a constant value for Q2>3 (GeV/c)2.

2 data tables
Table 1

Magnetic form factors.

Table 2

Electric form factors.


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.


Characteristics of the pion production and proton emission processes in proton - carbon nuclear collisions at 4.2-GeV/c momentum

Strugalski, Z. ; Sultanov, M. ;
JINR-E1-92-68, 1992.
Inspire Record 336351 DOI 10.17182/hepdata.39402

None

12 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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.


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.


Backward emitted protons in interactions of neutrinos with nuclei in photoemulsion. FNAL-564 experiment

Dayon, M. ; Rappoport, V. ; Smirnitsky, V. ; et al.
Z.Phys.C 56 (1992) 391-393, 1992.
Inspire Record 345621 DOI 10.17182/hepdata.14532

Backward emitted protons with momentump>0.3 GeV/c in interactions of neutrino in the energy range 10–200 GeV with photoemulsion nuclei were investigated. Energy spectrum slope parameter of backward protons was measured to beT0=48.9±7.9 MeV. TheA-dependence power index of relative mean yield of backward protons was found to bea=0.68±0.12. A drop in the mean yield of backward protons at the four momentum squared over ∼15 (GeV/c)2 (the neutrino energy over ∼50 GeV) was observed.

3 data tables
Table 1

NUCLEUS IS AVERAGE NUCLEI OF NUCLEAR EMULSION, <A> ABOUT 80.

Table 2

NUCLEUS IS AVERAGE NUCLEI OF NUCLEAR EMULSION, <A> ABOUT 80.

Table 3

NUCLEUS IS AVERAGE NUCLEI OF NUCLEAR EMULSION, <A> ABOUT 80.


Study of intranuclear collision effects in interactions of K+ / pi+ mesons with Al and Au nuclei at 250-GeV/c.

The EHS/NA22 collaboration Agababyan, N.M. ; Ajinenko, I.V. ; Botterweck, F. ; et al.
Z.Phys.C 56 (1992) 371-380, 1992.
Inspire Record 345620 DOI 10.17182/hepdata.14529

Multiplicity, inclusive, correlation and collective characteristics of multiparticle production processes inK+ Al,K+ Au, π+ Al and π+ Au interactions at 250 GeV/c are studied with the European Hybrid Spectrometer, providing high statistics and almost 4 π acceptance for final state charged particles. It is shown that the proton energy spectrum practically does not depend on the target atomic weight, but the proton angular distributions reveal a strongA-dependence. In a model independent way, the average number of intranuclear collisions is extracted, and it is shown that their dominant part (60% for Al and 80% for Au) is caused by interactions of the non-leading particles produced in the target fragmentation. The multiplication ratio of the produced particles for the Au nucleus changes fromR≃40 at the smallest rapidities in the target fragmentation region, down toR=0.37±0.06 at the largest rapidities in the beam fragmentation region. It is found that the average total longitudinal momentum of the charged products of the beam fragmentation depends weakly on the number of leading hadron (cluster) intranuclear collisions which are characterized by a low inelasticity coefficient 〈k〉=0.17±0.03.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
An Experimental study of the process gamma gamma ---> pi+ pi-

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Field, J.H. ; et al.
Z.Phys.C 56 (1992) 381-390, 1992.
Inspire Record 345437 DOI 10.17182/hepdata.14534

Using the CELLO detector, we have measured cross sections for the processγγ→π+π− in the mass range 0.75–1.9 GeV/c2. A partial wave fit to the data indicates the presence of a sizeableS-wave amplitude with signs of resonant behaviour. Values for the γγ width of thef2(1270) are given, showing the model-dependence of this quantity. At higher dipion masses, the model of Brodsky and Lepage is found to give an order of magnitude description of the data.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Determination of $alpha_{s}$ in second order {QCD} from hadronic $Z$ decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Z.Phys.C 54 (1992) 55-74, 1992.
Inspire Record 333272 DOI 10.17182/hepdata.14603

Distributions of event shape variables obtained from 120600 hadronicZ decays measured with the DELPHI detector are compared to the predictions of QCD based event generators. Values of the strong coupling constant αs are derived as a function of the renormalization scale from a quantitative analysis of eight hadronic distributions. The final result, αs(MZ), is based on second order perturbation theory and uses two hadronization corrections, one computed with a parton shower model and the other with a QCD matrix element model.

9 data tables
Table 1

Experimental differential Thrust distributions.

Table 2

Experimental differential Oblateness distributions.

Table 3

Experimental differential C-parameter distributions.

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