Date

Pion Pair Production in Photon - Photon Collisions at {SPEAR}

Roussarie, A. ; Burke, D.L. ; Abrams, G.S. ; et al.
Phys.Lett.B 105 (1981) 304-308, 1981.
Inspire Record 166578 DOI 10.17182/hepdata.31056

We report a measurement of the cross section for the process γγ → π + π − at invariant masses 500 MeV/ c 2 < m ππ <2000 MeV/ c 2 . A value for the radiative width of the f(1270) tensor meson Γ f→ γγ = 3.6 ± 0.3 ± 0.5 KeV (helicity λ = 2) has been obtained from a fit to the observed ππ mass spectrum.

1 data table

DATA REQUESTED FROM AUTHORS.


Measurement of $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at Energies Up to 36.7-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J. ; et al.
Phys.Lett.B 103 (1981) 148-152, 1981.
Inspire Record 165288 DOI 10.17182/hepdata.31169

The differential cross sections of the reactions e + e − → e + e − and e + e − → λλ are measured at energies between 33.0 and 36.7 GeV. The results agree with the predictions of quantum electrodynamics. A comparison with the standard model of electroweak interaction yields sin 2 θ W = 0.25 ± 0.13.

2 data tables

No description provided.

No description provided.


Study of the Reaction $e^+ e^- \to 3 \pi^+ 3 \pi^-$ in the Total Energy Range 1400-{MeV} to 2180-{MeV}

Bisello, D. ; Bizot, J.C. ; Buon, J. ; et al.
Phys.Lett.B 107 (1981) 145-147, 1981.
Inspire Record 166353 DOI 10.17182/hepdata.31033

The e + e − → 3 π + 3 π − cross section has been measured between 1400 and 2180 MeV with the magnetic detector DM1 at the Orsay storage rings DCI. The cross section increases continuously above 1600 MeV and reaches 2 nb at the maximum explored energy, much larger than VDM previous estimates.

1 data table

No description provided.


Observation of a New Isoscalar Vector Meson in $e^+ e^- \to \omega \pi^+ \pi^-$ Annihilation at 1.65-{GeV}

Cordier, A. ; Bisello, D. ; Bizot, J.C. ; et al.
Phys.Lett.B 106 (1981) 155-158, 1981.
Inspire Record 166964 DOI 10.17182/hepdata.31042

The e + e − → ωπ + π − → π + π − π + π − π 0 cross section has been measured at DCI by the DMI experiment in the 1.4–2.2 GeV energy range. A bump in this cross section appears at 1.65 GeV above a small background, with 6.2 s.d. statistical significance. It can be interpreted as a new isoscalar vector meson: ω ′ or ø ′.

1 data table

THE INDIVIDUAL SYSTEMATIC ERRORS ARISE FROM THE UNCERTAINTY IN SUBTRACTING THE FIVE-PION (NON-OMEGA) BACKGROUND. THESE ERRORS ARE CORRELATED WITH THE STATISTICAL ERRORS.


Baryon Production in e+ e- Annihilation at PETRA

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 104 (1981) 325-329, 1981.
Inspire Record 166363 DOI 10.17182/hepdata.31062

Data on p and Λ production by e + e − -annihilation at CM energies between 30 and 36 GeV are presented. Indication for an angular anticorrelation in events with baryon-antibaryon pairs is seen.

3 data tables

No description provided.

No description provided.

AVERAGE NUMBER OF ANTIBARYONS PER HADRONIC EVENT. AN EXPONENTIAL SLOPE OF 2.5 GEV*-1 IN E WAS ASSUMED IN EXTRAPOLATING E*D3(SIG)/DP**3 TO ALL MOMENTA.


RESONANCE PRODUCTION BY TWO PHOTON INTERACTIONS AT SPEAR

Jenni, P. ; Burke, D.L. ; Telnov, Valery I. ; et al.
Phys.Rev.D 27 (1983) 1031, 1983.
Inspire Record 173430 DOI 10.17182/hepdata.23843

Two-photon interactions have been studied with the SLAC-LBL Mark II magnetic detector at SPEAR. The cross section for η′ production by the reaction e+e−→e+e−η′ has been measured at beam energies from 2.0 to 3.7 GeV. The radiative width Γγγ(η′) has been determined to be 5.8±1.1 keV (±20% systematic uncertainty). Upper limits on the radiative widths of the f(1270), A2(1310), and f′(1515) tensor mesons have been determined. A search has been made for production of the E(1420) by γγ collisions, but no signal is observed.

2 data tables

No description provided.

NO SIGNAL ABOVE BACKGROUND SEEN. UPPER LIMITS AT 95 PCT CL GIVEN.


SEARCH FOR NARROW QUARKONIUM STATES AND PAIR PRODUCTION OF NEW HEAVY QUARKS AT c.m. ENERGIES FROM 33-GeV TO 36.7-GeV

The CELLO collaboration Behrend, H.J. ; Chen, Ch. ; Field, J.H. ; et al.
DESY-81-029, 1981.
Inspire Record 166365 DOI 10.17182/hepdata.45222

None

1 data table

CONTINUOUS COVERAGE OF THREE ENERGY RANGES (33.00 TO 33.80, 34.00 TO 35.26 AND 36.08 TO 36.72 GEV PLUS SEVEN ADDITIONAL DATA POINTS AROUND 35.7 GEV).


Measurement of Hadron Production and Three Jet Event Properties at {PETRA} {MIT}

Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Lett.B 108 (1982) 63-66, 1982.
Inspire Record 166369 DOI 10.17182/hepdata.31009

We have performed a high statistics measurement of the production rate and the energy flow pattern of hadron events between √ s =33 and 36.7 GeV. The data show no evidence for the production of a new quark with charge 2 3 e . Planar events in e + e − →hadrons are shown to have three well separated jets. The production rate and the shape of three-jet events are compared with many models and we find that only the QCD model can explain the data.

1 data table

ENERGY SCAN WITH 7077 HADRON EVENTS.


Review of $e^+ e^-$ Experiments With Pluto From 3-{GeV} to 31-{GeV}

Criegee, Lutz ; Knies, Gerhard ;
Phys.Rept. 83 (1982) 151-280, 1982.
Inspire Record 166799 DOI 10.17182/hepdata.19326

The contributions of the PLUTO experiment to e + e − physics at collision energies in the range of 3–32 GeV are reviewed. The review briefly sketches the storage rings DORIS and PETRA at DESY, and describes the most important features of the PLUTO detector, of data processing, and of the analysis methods. It covers the physics results in the fields of electroweak interactions, of the heavy lepton τ and the search for still heavier leptons, of hadron production with evidence for quark and gluon jets, as well as for single and multiple gluon emission, of Y decays and their relation to QCD, and presents results in high-energy photon-photon interactions, including the first measurement of the photon structure function.

2 data tables

SUMMARY OF MEASUREMENTS OF R (REVISED FROM EARLIER PUBLICATIONS). RADIATIVE CORRECTIONS APPLIED. TAU HEAVY LEPTON CONTRIBUTION SUBTRACTED.

Summary of measurements of the cross section around the UPSI(1S) (revised from earlier publication Phys.Lett. 76B (1978) 243) with radiative corrections a pplied and leptons contribution subtracted. Data extracted from graph by VVE.


Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.
Phys.Lett.B 110 (1982) 82-86, 1982.
Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables

Data read from graph. Systematic error on M is of order of 2% or less.

Data read from graph.

No description provided.