Observation of a broad peak in the production of four charged pions by e+ e- collisions around 1.6 gev

Barbarino, G. ; Grilli, M. ; Iarocci, E. ; et al.
Lett.Nuovo Cim. 3 (1972) 689-692, 1972.
Inspire Record 77547 DOI 10.17182/hepdata.37365

None

1 data table

STATISTICAL ERRORS ONLY.


A STUDY OF e+ e- ANNIHILATION IN THE 1400-MeV TO 2250-MeV ENERGY RANGE WITH THE MAGNETIC DETECTOR DM2 AT DCI

Augustin, J.E. ; Ayach, L. ; Calcaterra, A. ; et al.
LAL-83-21, 1983.
Inspire Record 192321 DOI 10.17182/hepdata.13242

None

5 data tables

ASSUMING ABS(GE)=ABS(GM).

No description provided.

No description provided.

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Multi-Hadron Production from e+ e- Annihilation at 1.6 Center-of-Mass Energy

Esposito, B. ; Felicetti, F. ; Marini, A. ; et al.
Lett.Nuovo Cim. 19 (1977) 21-31, 1977.
Inspire Record 124164 DOI 10.17182/hepdata.37424

None

3 data tables

SINGLE CHARGED PARTICLE MOMENTUM DISTRIBUTION.

No description provided.

No description provided.


STUDY OF (PI+ PI- PI+ PI-) AND (PI+ PI- PI0) CHANNEL IN E+ E- ANNIHILATION AT 1.450-GEV - 1.875-GEV center-of-mass ENERGY

Esposito, B. ; Marini, A. ; Ronga, F. ; et al.
Lett.Nuovo Cim. 28 (1980) 195-200, 1980.
Inspire Record 158282 DOI 10.17182/hepdata.37366

None

2 data tables

No description provided.

POSSIBLE EVIDENCE FOR OMEGA(1670) RESONANCE.


A Study of the Possible Existence of rho-prime and rho-prime-prime

Alles-Borelli, V. ; Bernardini, M. ; Bollini, D. ; et al.
Nuovo Cim.A 30 (1975) 136, 1975.
Inspire Record 100204 DOI 10.17182/hepdata.37699

The possible existence of new vector mesons above the ρ is investigated. The conclusion is that our data are compatible with the existence of the ρ′-meson only if we assume as a firm theoretical prediction the Gounaris-Sakurai tail of the standard ρ-meson. Furthermore our data are compatible with the existence of the ρ″-meson if we assume the validity of the\(\bar p\)p model for the calculation of the multihadron cross-section.

3 data tables

THESE MEASUREMENTS OF THE PION FORM FACTOR ARE GIVEN IN D. BOLLINI ET AL., NCL 14, 418 (1975).

THESE MEASUREMENTS OF THE FOUR CHARGED PION CROSS SECTION ARE GIVEN IN M. BERNARDINI ET AL., PL 53B, 384 (1974).

THESE MEASUREMENTS OF THE TOTAL HADRONIC CROSS SECTION ARE GIVEN IN M. BERNARDINI ET AL., PL 51B, 200 (1974).


Cross-section of the Reaction $e^+ e^- \to \pi^+ \pi^- \pi^+ \pi^-$ for Center-of-mass Energies From 890-{MeV} to 1100-{MeV}

Cordier, A. ; Delcourt, B. ; Eschstruth, P. ; et al.
Phys.Lett.B 81 (1979) 389-392, 1979.
Inspire Record 132828 DOI 10.17182/hepdata.27360

We present the results of a measurement of the cross section oof the reaction e + e − → π + π − π + π − from 890 to 1100 MeV in the center of mass, obtained with a magnetic detector at the Orsay Storage Ring ACO. With respect to previous experiments, the present one offers the possibility of reconstructing events with at least one constraint and his improved statistics. We find that our measurement of the cross section for e + e − → π + π − π + π − is compatible with quasi two-body production of π A 1 ( m A1 = 1.1 GeV, Γ A1 ∼ 0.2−0.3 GeV), through the ϱ and ϱ′(1600) intermediate states. We were able to states. We were able to determine the cross section of this reaction at the energy of the φ meson and consequently an upper limit on the branching ratio of φ → π + π − π + π − .

1 data table

UPPER LIMIT FOR PHI --> 4PI.


Multi-Pion Production Below 1.1-GeV by e+ e- Annihilation

Cosme, G. ; Courau, A. ; Dudelzak, B. ; et al.
Phys.Lett.B 63 (1976) 349-351, 1976.
Inspire Record 115717 DOI 10.17182/hepdata.27637

The production of multipion events by e + e − annihilation has been measured at centre of mass energies 915,990 and 1076 MeV. Both channels e + e − → π + π − π o and e + e − → π + π − π + π − have been analysed. An energy threshold effect analysed. An energy threshold effect around 919 MeV ( m ω + m π o ) has been evidenced for the π + π − π o π o channel and the cross section is consistent with the quasi two-body process e + e − → ωπ o . The cross section for π + π − π + π − is lower by an order of magnitude and increases with the energy.

2 data tables

SYSTEMATIC ERROR INCLUDED. RADIATIVE EFFECT (<15 PCT) INCLUDED.

MULTIHADRON PRODUCTION CROSS SECTION DEDUCED AS SUM OF FOUR PION CHANNELS.


Multihadron production in e+ e- collisions at high energy

Grilli, M. ; Iarocci, E. ; Spillantini, P. ; et al.
Nuovo Cim.A 13 (1973) 593-644, 1973.
Inspire Record 87243 DOI 10.17182/hepdata.1179

Multihadron production by electron-positron colliding beams has been investigated for total centre-of-mass energies ranging from 1.2 to 2.4 GeV. The total cross-section, σtot ≡ σ(e+e−→π+π−+ + anything), is of the order of σμμ ≡ σ(e+e−→μ+μ−), with a threshold near 1 GeV. Partial cross-sections for the various channels are also derived. The cross-section of the specific channel e+e−→π+π−π+π− exhibits an energy dependence which is suggestive of a heavier vector meson, ρ' (mρ,≈ 1.6 GeV,Гρ, ≈ 350 Mev), having the same quantum numbers as the ρ-meson. An upper limit is given for the coupling constantfρ′ (fρ′/4π<18, wherefρ′=mρ′2e/gγρ′). Final states withG+ parity are found to be much more abundant than those withG− parity. The average multiplicity (charged plus neutral final-state pions) is found to be betweet 4 and 5 over all the energy range explored.

3 data tables

No description provided.

VALUES OF R CALCULATED FROM TOTAL CROSS SECTION.

No description provided.