Date

Search for Top Quark and a Test of Models Without Top Quark at the Highest {PETRA} Energies

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 799, 1983.
Inspire Record 182337 DOI 10.17182/hepdata.20549

With a PETRA energy scan in ≤30-MeV steps, the continuum production of open top quark up to 38.54 GeV is excluded. Over regions of energy scan from 29.90 to 38.63 GeV limits are set on the product of hadronic branching ratio and electronic width BhΓee for toponium to be less than 2.0 keV at the 95% confidence level. By a search for flavor-changing neutral currents in b decay, models without a top quark are excluded.

4 data tables

MEASUREMENT OF R IN ENERGY SCAN FROM SQRT(S) = 29.9 TO 3.146 AND 33.0 TO 36.72.

MEASUREMENT OF R IN THE RANGE SQRT(S) 37 TO 38.63 GEV.

THRUST DISTRIBUTION FOR EVENTS IN THE RANGE SQRT(S) 37.94 TO 38.63 AND 38.54 TO 38.63.

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Limits on $J/\psi$ and $\Upsilon$ Production in $e^+ e^-$ Interactions at $\sqrt{s}=29$-{GeV}

Matteuzzi, C. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Lett.B 129 (1983) 141-144, 1983.
Inspire Record 189580 DOI 10.17182/hepdata.30662

A search has been made for the inclusive production of J ψ (3.1) and ϒ (9.4) mesons in e + e − interactions at 29 GeV, via their decay into two leptons. No signal is observed in the J ψ region, nor in the ϒ region. The limits on the cross sections are σ ( e + e − → ψX ) < 4.4 × 10 −36 cm 2 , and σ ( e + e − → ϒX ) < 4.7 × 10 −36 cm 2 . The same data yield limits on the branching ratios for the b quark BR ( b → ψX ) < 4.9% and BR ( b → ℓ + ℓ − X ) < 0.8%.

2 data tables

No description provided.

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A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 2051, 1983.
Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables

DATA REQUESTED FROM THE AUTHORS.

No description provided.


Experimental Study of Inclusive Muon Spectra at PETRA

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 51 (1983) 443, 1983.
Inspire Record 13422 DOI 10.17182/hepdata.20492

The results of a high-statistics study of inclusive muon spectra at PETRA are reported. Improved mass limits have been obtained for heavy quarks, heavy leptons, and charged Higgs particles. It is shown that the fragmentation properties of b quarks and c quarks are different, with the mean fragmentation variables 〈zb〉=0.75±0.03±0.06, 〈zc〉=0.46±0.02±0.05 and the average semileptonic branching ratio for the B and C hadrons R(B)=(10.5±1.5±1.3)%, R(C)=(11.5±1.0±1.7)%.

5 data tables

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A Summary of Recent Experimental Results From Mark-$J$: High-energy $e^+ e^-$ Collisions at {PETRA}

The Mark-J collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rept. 109 (1984) 131, 1984.
Inspire Record 196567 DOI 10.17182/hepdata.30997

None

6 data tables

DATA ARE CORRECTED FOR TWO-PHOTON AND TAU PRODUCTION EFFECTS, ACCEPTANCE AND QED RADIATIVE EFFECTS UP TO ORDER ALPHA**3. THERE IS ALSO A 6 PCT NORMALISATION ERROR NOT INCLUDED. THE OVERALL AVERAGE VALUE OF R FROM THIS DATA IS 3.88 +- 0.04 +- 0.22.

No description provided.

SEE PRL 55, 665 FOR MOST RECENT VALUES OF THE MU+ MU- CROSS SECTIONS.

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CHARGED HADRON PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 52 (1984) 577, 1984.
Inspire Record 195994 DOI 10.17182/hepdata.20439

The inclusive production cross sections and mean multiplicities of π±, K±, p, and p¯ in e+e− annihilation at a c.m. energy of 29 GeV have been measured with the time-projection chamber at PEP, using ionization energy loss to separate particle types. On average, 10.7±0.6 π±, 1.35±0.13 K±, and 0.60±0.08 p,p¯ are contained in an annihilation event. The fraction of pions among final-state particles decreases from over 95% at 0.3 GeV/c momentum to about 60% at high momentum; the kaon and proton fractions rise correspondingly.

7 data tables

PARTICLE FRACTIONS.

PARTICLE FRACTIONS.

PARTICLE FRACTIONS.

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Search for New Particles in $e^+ e^-$ Annihilation From 39.79-{GeV} to 45.52-{GeV}

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 53 (1984) 134, 1984.
Inspire Record 199819 DOI 10.17182/hepdata.20429

We have searched for resonances in the reaction e+e−→hadrons, γγ, μμ, and ee, in the energy range 39.79

1 data table

No description provided.


phi MESON PRODUCTION IN e+ e- ANNIHILATIONS AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 52 (1984) 2201, 1984.
Inspire Record 200105 DOI 10.17182/hepdata.20445

Production of φ mesons in e+e− annihilation at a center-of-mass energy of 29 GeV has been observed with the time-projection chamber detector at the PEP storage ring. The φ production rate has been measured in the energy range 0.075

3 data tables

No description provided.

EXTRAPOLAATION TO ALL X USES LUND MONTE CARLO PREDICTIONS.

ERRORS ARE BOTH STATISTICAL AND SYSTEMATIC. PT IS MEASURED RELATIVE TO THE EVENT THRUST AXIS, AND IS FOUND TO HAVE A MEAN VALUE OF 1.0 +- 0.4 GEV.


PROMPT ELECTRON PRODUCTION IN e+ e- ANNIHILATIONS AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Z.Phys.C 27 (1985) 39, 1985.
Inspire Record 200040 DOI 10.17182/hepdata.1895

We have measured the inclusive prompt electron cross section over a wide momentum range (P>0.5 GeV/c) with the PEP-4 TPC detector. The semielectronic branching fractions of thec andb quarks are (9.1±0.9 (stat.)±1.3 (syst.))% and (11.0±1.8±1.0)%, respectively. Theb quark fragmentation function peaks at highz with 〈zb〉=0.74±0.05±0.03. The axial couplings to the neutral current areac=2.3±1.4±1.0 for thec quark andab=−2.0±1.9±0.5 for theb quark.

3 data tables

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CHARACTERISTICS OF PROTON PRODUCTION IN JETS FROM e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 53 (1984) 130, 1984.
Inspire Record 201475 DOI 10.17182/hepdata.20437

Proton production in e+e− annihilation at 29 GeV has been studied with the time projection chamber. Measurements of the dependence of proton fractions on momentum, transverse momentum with respect to the jet axis, hadron multiplicity, and event sphericity are reported. Our results are consistent with the assumption that primary baryons and mesons have similar production spectra, and indicate that protons provide more direct probes of underlying fragmentation phenomena than do pions.

1 data table

No description provided.