Derrick, M.
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$\psi \psi$ Production and Limits on Beauty Meson Production From 400-{GeV}/$c$ Protons

The NA3 collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.
Phys.Lett.B 158 (1985) 85, 1985.
Inspire Record 213878 DOI 10.17182/hepdata.30379

From a study of multimuon events obtained in a high luminosity proton-platinum experiment at 400 GeV/ c , we find 5 ± 4 ψψ events, which correspond to a production cross section σ ( ψψ = 27 ± 10 pb. The observed production is compared to the ψψ events previously found in the same apparatus from incoming π − ; a comparison with QCD predictions is performed, giving a good agreement with expectations from gluon-gluon fusion. Finally, using like-sign dimuon, trimuon and quadrimuon events, we give model-dependent upper limits on beauty meson production: 2 nb/nucleon for central models, 20 nb/nucleon for diffractive production.

1 data table
Table 1

No description provided.


Observation of Anti-deuteron Production in Electron - Positron Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Lett.B 157 (1985) 326-332, 1985.
Inspire Record 214358 DOI 10.17182/hepdata.30409

The production of antideuterons has been observed in electron-positron annihilations at center-of-mass energies around 10 GeV. Antideuterons have been identified unambiguously by their energy loss in the drift chamber, their time-of-flight and the pattern of their energy deposition in the shower counters of the ARGUS detector. The production rate in the momentum range (0.6−1.8) GeV/ c is (1.6 −0.7 +1.0 ) × 10 −5 per hadronic event.

2 data tables
Table 1

Results from 6 antideuterons detected (3 from UPSI(2S), 2 from (IS) and 1 from (4S)).

Table 2

No description provided.


rivet Analysis
Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 54 (1985) 2568, 1985.
Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

WITH THE FOLLOWING ANGLE CUTS ON THE DECAY REGIONS. PHI DECAY - ABS(COS(THETA)) >0.5.

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Inclusive Photoproduction of Strange Baryons at 20-{GeV}

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Armenteros, R. ; Bacon, T.C. ; et al.
Phys.Rev.D 32 (1985) 2869-2882, 1985.
Inspire Record 213727 DOI 10.17182/hepdata.23548

Cross sections are presented for the inclusive photoproduction of KS0, Λ, Λ¯, Ξ−, Ξ¯−, Σ0, and Σ*±(1385) at 20 GeV. An upper limit to Ω− production is also given. The data come from 284 000 hadronic events photoproduced in the SLAC 1-m hydrogen-bubble-chamber hybrid facility exposed to a nearly monochromatic, polarized 20-GeV backscattered photon beam. A comparison of the KS0, Λ, Λ¯, and Ξ− rates per inelastic event to π±p data show that γp rates are consistent with being higher than the π±p rates, providing evidence of an ss¯ component of the photon. The pair cross sections for KS0KS0, KS0Λ, KSoΛ¯, and ΛΛ¯ are presented. The xF distributions of the Λ, Λ¯, and Ξ− are compared to a quark-diquark fusion model, giving information on strange-baryon photoproduction mechanisms.

1 data table
Table 1

No description provided.


Measurement of $e^+ e^- \to \mu^+ \mu^-$: A Test of Electroweak Theories

The Mark-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.
Phys.Rev.Lett. 55 (1985) 665, 1985.
Inspire Record 214607 DOI 10.17182/hepdata.3237

We use the reaction e+e−→μ+μ−, in the Mark J detector at the DESY high-energy e+e− collider PETRA, to test the standard electroweak theory and find good agreement. We also set limits on the parameters of several extended gauge theories.

6 data tables
Table 1

CROSS SECTION MEASUREMENT RELATIVE TO PREDICTED QED CROSS SECTION.

Table 2

FORWARD-BACKWARD ASYMMETRY. THE SYSTEMATIC ERROR IN THE ASYMMETRY IS <0.5 PCT.

Table 3

ANGULAR DISTRIBUTIONS NOT GIVEN IN PAPER. SUPPLIED BY E.DEFFUR.

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First Measurement of the Reaction $\pi^- e \to \pi^- \pi^0 e$

Amendolia, S.R. ; Arik, M. ; Badelek, B. ; et al.
Phys.Lett.B 155 (1985) 457-460, 1985.
Inspire Record 213172 DOI 10.17182/hepdata.30413

The first observation of neutral pion production in π e inelastic scattering is presented. The cross section at 300 GeV for | t ‖>62;10 −3 (GeV / c ) 2 is 2.11 ± 0.47 nb, in good agreement with the theory of PCAC anomalies with 3 quark colours.

1 data table
Table 1

No description provided.


Measurements of Tau Lepton Production and Decay

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 28 (1985) 1, 1985.
Inspire Record 213241 DOI 10.17182/hepdata.16019

We have studied 419 τ pair events produced in the reactione+e−→τ+ τ− at a c.m. energy of 34.6 GeV. We measure the cross section and angular distribution, as well as the decay branching ratios. The production characteristics are consistent with the Standard Electroweak Model predictions of γ andZ0 interference. The branching ratios are generally consistent with the τ decaying according to standard weak interaction principles, but we observe somewhat more decays resulting in single charged hadrons plus neutrals than are predicted by present theory.

3 data tables
Table 1

Corrected for radiative effects.

Table 2

Measured cross section relative to Standard Model Prediction.

Table 3

Asymmetry based on fits to angular distribution.


Intermediate Mass Dimuon Events at the {CERN} $p \bar{p}$ Collider at $\sqrt{s}=540$-{GeV}

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.
Phys.Lett.B 155 (1985) 442-456, 1985.
Inspire Record 213203 DOI 10.17182/hepdata.49630

We report the observation of 21 dimuon events at the CERN p p Collider with the UA1 detector. The events range in invariant dimuon mass from 2 to 22 GeV / c 2 . The properties of these events are given. The bulk of the events are consistent with heavy-flavour production (mainly b b ) with a few candidates for Drell-Yan production. There remain a few events which are difficult to interpret in terms of these processes, in particular two events with isolated, like-sign muons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


New Results on the Reaction $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.D 31 (1985) 2352, 1985.
Inspire Record 212767 DOI 10.17182/hepdata.3935

We have measured the process e+e−→μ+μ− at √s =29 GeV using the High Resolution Spectrometer at SLAC PEP. The forward-backward charge asymmetry is Aμμ=-(4.9±1.5±0.5)% based on 5057 events. A subsample of 3488 μ+μ− events in the angular range ‖cosθ‖<0.55 gives a cross-section ratio of Rμμ=0.990±0.017±0.030. The resulting couplings of the weak neutral current are gaegaμ=0.208±0.064± 0.021 and gvegvμ=0.027 ±0.051±0.089. The QED cutoff parameters are Λ+>170 GeV and Λ−>146 GeV at 95% C.L.

4 data tables
Table 1

Corrected for acceptance and O(alpha**3) QED radiation. Numerical values taken from SUGANO-ANL-HEP-CP-84-90.

Table 2

Forward-backward asymmetry based on fit to angular distribution. Result is given combined with earlier data from BENDER et al.

Table 3

No description provided.

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ANALYSIS OF THE REACTION PI- P ---> PI0 ETA N AT 40-GEV/C BEAM MOMENTUM.

The SERPUKHOV-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.
Yad.Fiz. 41 (1985) 126-136, 1985.
Inspire Record 218766 DOI 10.17182/hepdata.2594

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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