Johnson, J.A.
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A Comparison of the Particle Flow in Three Jet and Radiative Two Jet Events From $e^+ e^-$ Annihilation at $e$({CM}) = 29-{GeV}

Sheldon, P.D. ; Trilling, G. ; Petersen, A. ; et al.
Phys.Rev.Lett. 57 (1986) 1398, 1986.
Inspire Record 230941 DOI 10.17182/hepdata.20219

We have made a detailed comparison of the charged-particle flow in three-jet events (e+e−→qq¯g) and radiative two-jet events (e+e−→qq¯γ) from e+e− annihilation at Ec.m.=29 GeV. Accurate comparisons can be made because these two event types have similar topologies. In the angular region between the quark and antiquark jets, we observe substantially fewer charged tracks in the two-jet events than in the radiative three-jet events.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Tests of Quantum Electrodynamics With 2, 3 and 4 Photon Final States From $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 35 (1987) 1, 1987.
Inspire Record 230165 DOI 10.17182/hepdata.23424

High-precision measurements of electron-positron annihilation into final states of two, three, and four photons are presented. The data were obtained with the MAC detector at the PEP storage ring of the Stanford Linear Accelerator Center, at a center-of-mass energy of 29 GeV. The measured e+e−→γγ differential cross section is used to test the validity of quantum electrodynamics (QED) in this energy range; it agrees well with QED, and the limit on cutoff parameters for the electron propagator is Λ>66 GeV. The measurement of e+e−→γγγ is used to test the QED calculations of order α3 and to search for anomalies that would indicate the existence of new particles; the agreement with QED is excellent and no anomalies are found. Two events from the reaction e+e−→γγγγ are found, in agreement with the QED prediction.

3 data tables
Table 1

Errors are combined statistical and systematics.

Table 2

No description provided.

Table 3

Two 4gamma events are observed corresponding to a cross section of 0.02 PB.


SEARCH FOR SINGLE PHOTONS FROM RADIATIVE NEUTRINO OR SUPERSYMMETRIC

Ford, William T. ; Qi, N. ; Read, Alexander L. ; et al.
SLAC-PUB-4003, 1986.
Inspire Record 230016 DOI 10.17182/hepdata.23507

None

1 data table
Table 1

No description provided.


Electroweak Effects in $e^+ e^- \to e^+ e^-$ at $\sqrt{s}=29$-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 35 (1987) 10-18, 1987.
Inspire Record 230164 DOI 10.17182/hepdata.3835

A high-precision measurement of the differential cross section for Bhabha scattering (e+e−→e+e−) is presented. The measurement was performed with the MAC detector at the PEP storage ring of the Stanford Linear Accelerator Center, at a center-of-mass energy of 29 GeV. Effects due to electroweak interference are observed and agree well with the predictions of the Glashow-Salam-Weinberg model. The agreement between the data and the electroweak prediction rules out substructure of the electron up to mass scales of 1 TeV.

5 data tables
Table 1

Error contains both statistics and systematics.

Table 2

No description provided.

Table 3

No description provided.

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Measurement and QCD Analysis of the Photon Structure Function F2 (x, Q**2)

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Nucl.Phys.B 281 (1987) 365, 1987.
Inspire Record 230592 DOI 10.17182/hepdata.33588

We present a measurement of the hadronic structure function F 2 γ ( x , Q 2 ) of the photon in the Q 2 range from 10 to 100 GeV 2 . Data were taken with the PLUTO detector at the e + e - storage ring PETRA. This measurement and previous PLUTO measurements in the Q 2 range of 1.5 to 16 GeV 2 are compared with higher order QCD calculations. The structure function is consistent with the predicted log Q 2 behaviour when charm contributions are subtracted. The x dependence can be well described for 0.1 < x < 0.9 by the regularization scheme of Antoniadis and Grunberg. Within their scheme the data yield a value of Λ MS = 183 + 65/ −40( stat. ) + 46/ −36( sys. ) MeV for the QCD scale parameter.

5 data tables
Table 1

Data read from graph.

Table 2

Data read from graph.

Table 3

Data read from graph.

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A Measurement of the Strong Coupling Constant $\alpha^- s$ to Complete Second Order

The Mark-J collaboration Adeva, B. ; Anderhub, H. ; Ansari, S. ; et al.
Phys.Lett.B 180 (1986) 181-184, 1986.
Inspire Record 231302 DOI 10.17182/hepdata.6535

The strong interaction coupling constant α s has been measured with a new method, the planar triple energy correlation in the reaction e + e - → hadrons at center-of-mass energies ranging from 14 GeV to 46.78 GeV. A complete second-order perturbative QCD calculation was used. Λ MS = 110 ± 30 −55 +70 MeV is found.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Observation of the Leading $K^*$ L Excitation Series From $J P=1$- Through 5- in the Reaction $K^- p \to K^- \pi^+ n$ at 11 GeV/$c$

Aston, D. ; Awaji, N. ; D'Amore, J. ; et al.
Phys.Lett.B 180 (1986) 308, 1987.
Inspire Record 231083 DOI 10.17182/hepdata.6544

High statistics data for the reaction K − p→K − π + n at 11 GeV / c have been obtained in the LASS spectrometer at SLAC. A spherical harmonic moments analysis provides clear evidence for the production of the complete leading orbitally excited K ∗ series up through J P = 5 − . New measurements are made of the masses and widths of the 1 − K ∗ (892), 2 + K ∗ (1430 ), 3 − K ∗ (1780), and 4 + K ∗ (2060), and evidence is presented for the production of a new K ∗ state at 2382 MeV / c 2 with spin-parity 5 − .

21 data tables
Table 1

Unnormalised acceptance corrected spherical moments.

Table 2

Correlation matrices.

Table 3

Correlation matrices.

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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.


The Production and Decay of Tau Leptons

The Mark-J collaboration Adeva, B. ; Ansari, S. ; Becker, U. ; et al.
Phys.Lett.B 179 (1986) 177-182, 1986.
Inspire Record 230298 DOI 10.17182/hepdata.14556

A study of τ-lepton production in the CMS energy region from 14 to 46.8 GeV at PETRA is reported. The cross section, the decay branching ratio into μν ν , and the electroweak parameters are determined with a total integrated luminosity of 115 pb −1 .

4 data tables
Table 1

Total cross section calculated from measured channel cross section assuming BR(tau-mu) = 17.6 pct. SIG(Q=MU) is the QED point cross section.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Hadronic Production Cross-Sections Measured in Proton - Nucleus Collisions at s**(1/2) = 27.4-GeV

Crittenden, J.A. ; Hsiung, Y.B. ; Kaplan, D.M. ; et al.
Phys.Rev.D 34 (1986) 2584, 1986.
Inspire Record 231109 DOI 10.17182/hepdata.23462

We present results on the production of hadrons in collisions of 400-GeV/c protons with beryllium, copper, and tungsten nuclei. The data cover the region from 5.6 to 8.0 GeV/c in the transverse momentum of the final-state hadron and from 73° to 102° in the proton-nucleon center-of-momentum frame production angle theta*. The restriction of the data to values of xT (xT=2pT/ √s ) greater than 0.4 enriches the sample with hard collisions of valence quarks. Asymmetries about theta*=90° reflect the presence of neutrons in the target nuclei. The variation of the atomic-weight dependence parameter α with production angle is discussed in the context of the phenomenology of nucleonic structure within nuclei. We also extrapolate our measurements to a ‘‘deuteron’’ target to minimize nuclear effects and compare the result to QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.