Gerhards, R.
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$\Lambda(c$) Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Giles, R.T. ; Hassard, J. ; et al.
Phys.Rev.Lett. 55 (1985) 923, 1985.
Inspire Record 214874 DOI 10.17182/hepdata.20302

We have observed Λc baryons in nonresonant e+e− annihilation at energies around s=10.5 GeV through their decay to Λπ+π+π−. We measure the branching fraction to be (2.8 ± 0.7 ± 1.1)%. The momentum spectrum of the Λc is similar to that of charmed mesons, providing a constraint on models of charmed-quark hadronization.

2 data tables
Table 1

No description provided.

Table 2

Data are extrapolated over whole x range using the 'Peterson' formula.


$\tau$ Leptonic Branching Ratios and a Search for Goldstone Decay

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 55 (1985) 1842, 1985.
Inspire Record 215995 DOI 10.17182/hepdata.20284

Pairs of τ leptons produced at s=3.77 GeV have been studied in eμ, ee, and μμ final states. The leptonic branching ratios have been measured to be B(τ→eνν)=(18.2±0.7±0.5)% and B(τ→μνν)=(18.0±1.0±0.6)%. Limits have been set for the two-body decays τ→eG and τ→μG, where G is a light Goldstone boson.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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First Observation and Cross-section Measurement of $\nu_e e^- \to \nu_e e^-$

Allen, R.C. ; Bharadwaj, V. ; Brooks, G.A. ; et al.
Phys.Rev.Lett. 55 (1985) 2401, 1986.
Inspire Record 215874 DOI 10.17182/hepdata.20326

We report the first observation and cross-section measurement of νe+e−→νe+e−. Using neutrinos of energy less than 53 MeV, we observed 63±17 events consistent with ν+e−→ν+e−, of which 51±17 events are assigned to νe+e−→νe+e−. The resulting cross section, {[8.9±3.2(statistical) ±1.5(systematic)]×10−45 cm2/MeV} Eν, agrees with standard electroweak theory, rules out constructive interference between weak charged-current and neutral-current interactions, and begins to indicate the existence of interference between these two interactions.

1 data table
Table 1

No description provided.


NEUTRAL STRANGE PARTICLE PRODUCTION IN NEUTRINO CHARGED CURRENT INTERACTIONS AT 3-GeV TO 30-GeV

Ammosov, V.V. ; Ardashev, E.N. ; Ivanilov, A.A. ; et al.
Z.Phys.C, 1985.
Inspire Record 222758 DOI 10.17182/hepdata.10525
15 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Hadron Production in $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.D 35 (1987) 2639, 1987.
Inspire Record 215848 DOI 10.17182/hepdata.23381

Data from the High Resolution Spectrometer at the SLAC storage ring PEP have been used to study the inclusive production of baryons and mesons. Time-of-flight measurements are used to identify the charged hadrons. Neutral hadrons are identified from effective-mass peaks associated with their decay into two charged particles. Cross sections and other inclusive production characteristics are presented for π±, K±, and K0 (K¯0) mesons, and for the baryons (antibaryons) p (p¯) and Λ (Λ¯). The ratio of the inclusive cross section to the point cross section for the K0 and K¯0 mesons is R(K0,K¯0)=6.15±0.13±0.25, and for Λ and Λ¯, R(Λ,Λ¯)=0.846±0.036±0.085. The neutral-hadron differential cross sections are compared with the predictions of the Lund string model.

8 data tables
Table 1

Charged particle fractions. Errors contain systematic uncertainties.

Table 2

Charged particle invariant cross sections. Errors contain systematic uncertainties.

Table 3

Charged particle invariant cross sections. Errors contain systematic uncertainties.

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INCLUSIVE JET PRODUCTION AT S**(1/2) = 546-GeV

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.
CERN-EP-85-116, 1985.
Inspire Record 216597 DOI 10.17182/hepdata.50065

None

1 data table
Table 1

No description provided.


Measurement of Total Cross-sections for $\pi^0$ Photoproduction on Nuclei in the $\Delta$ Resonance Region

Arends, J. ; Detemple, P. ; Floss, N. ; et al.
Nucl.Phys.A 454 (1986) 579-588, 1986.
Inspire Record 214936 DOI 10.17182/hepdata.50168

Total cross sections for π 0 photoproduction on Be, C, Al, Cu, Sn and Pb have been measured in the photon energy range k = 220–450 MeV using the tagged photon beam of the Bonn 500 MeV synchrotron. The data show a broad maximum around k = 350 MeV. The A -dependence can be described by σ A ∝ A 0.66 . The results are compared to charged pion production and to total hadronic cross sections.

1 data table
Table 1

No description provided.


A Measurement of the Total Cross-section and a Study of Inclusive Muon Production for the Process $e^+ e^- \to$ Hadrons in the Energy Range Between 39.79-{GeV} and 46.78-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Phys.Lett.B 160 (1985) 337-342, 1985.
Inspire Record 216799 DOI 10.17182/hepdata.30375

The total cross section and the inclusive muon cross section for the process e + e − → hadrons have been measured in the center of mass energy range between 39.79 and 46.78 GeV. The ratio R shows no significant structure. It has an average value of 4.13±0.08±0.14. An upper limit is set on the production of narrow resonances. Limits are obtained for pair-produced heavy quarks. The data are compared with the standard electroweak interaction model including QCD corrections taking into account the five known types of quarks. Upper limits are given for a possible structure of quarks and for effects of color octet leptons.

1 data table
Table 1

Figure 1 also shows energy scan of 'R'.


Comparison of Three Jet and Two Jet Cross-Sections in p anti-p Collisions at the CERN SPS p anti-p Collider

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.
Phys.Lett.B 158 (1985) 494, 1985.
Inspire Record 214736 DOI 10.17182/hepdata.30390

Results are presented on two-jet and three-jet cross sections, measured in the UA1 experiment at the CERN Super Proton Synchrotron (SPS) pp̄ Collider, at the highest available subprocess cms energies ( s ̂ >150 GeV ). Precise measurements of the two-jet angular distribution are consistent with previous results but show significant scale-breaking effects. The three-jet Dalitz plot and the three-jet angular distributions show evidence for final- and initial-state bremsstrahlung processes, in agreement with the leading-order QCD predictions. A comparison of the yield of wide-angle three-jet events with the yield of two-jet events at smaller scattering angles gives for the strong interaction coupling constant: α s ( K 3J K 2J )=0.16±0.02±0.03 at Q 2 ≈4000 GeV 2 , where the factor K 3J K 2J may plausibly be assumed to be close to unity.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charm Hadron Properties in 360-GeV/c $\pi^-$ p-Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Z.Phys.C 31 (1986) 491-511, 1986.
Inspire Record 214935 DOI 10.17182/hepdata.15883

A study of the properties of charm particles produced in 360 GeV/c π-p interactions is reported. The experiment was performed using the high resolution hydrogen bubble chamber LEBC in association with the European Hybrid Spectrometer at the CERN SPS. Details of the exposure and operation of the spectrometer are given and the methods used to extract the charm data are presented. The essential physics results on the decay properties (lifetime, branching ratios) as well as on the hadroproduction properties (cross sections forD,\(\bar D\),F, Λc,D, correlations between charm particles) are given.

2 data tables
Table 1

No description provided.

Table 2

No description provided.