1
From a two Breit-Wigner resonance fit to the 4${{\mathit \pi}}$ mass distribution produced in ultraperipheral ${}^{}\mathrm {Pb}−{}^{}\mathrm {Pb}$ collisions.
2
Simple relativistic Breit-Wigner fit with model dependent width.
3
Simple relativistic Breit-Wigner fit with constant width.
6
Skew mass distribution compensated by Ross-Stodolsky factor.
References:
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2026
PL B872 140006
Exclusive four pion photoproduction in ultraperipheral Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV
ACHASOV
1997
PR D55 2663
${{\mathit \rho}^{\,'}}$'s in Analyzing ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Annihilation, MARK III, LASS and ARGUS Data
CORDIER
1982
PL 109B 129
A Study of the ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ 2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$ Reaction in the 1.4 $−$ 2.18 GeV Energy Range
ASTON
1981E
NP B189 15
The Reaction ${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}$2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$ for Photon Energies from 25 to 70 GeV
DIBIANCA
1981
PR D23 595
Resonant Structure in the ${{\mathit \pi}^{+}}$ ${{\mathit \pi}^{+}}$ ${{\mathit \pi}^{-}}$ ${{\mathit \pi}^{-}}$ System between 1.5 and 1.9 GeV
BACCI
1980
PL 95B 139
Measurement of the ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Cross Section in the ${{\mathit \rho}^{\,'}{(1600)}}$ Energy Region
KILLIAN
1980
PR D21 3005
Observation of Meson Resonances in Electroproduction
ATIYA
1979B
PRL 43 1691
High Energy Photoproduction of ${{\mathit \rho}^{\,'}{(1600)}}$
ALEXANDER
1975
PL 57B 487
Measurement of the ${{\mathit \gamma}}−$V Coupling Constants and $\sigma _{T}(V{{\mathit d}}$) from Coherent ${{\mathit \gamma}}{{\mathit d}}$ Interactions at 7.5 GeV
CONVERSI
1974
PL 52B 493
On the Possible Existence of a Vector Meson ${{\mathit \rho}{(1250)}}$
SCHACHT
1974
NP B81 205
Resonance Production in the Reaction ${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ in the Energy Range $\mathit E_{{{\mathit \gamma}}}$ = 3.0-18.0 GeV
BINGHAM
1972B
PL 41B 635
Observation of a Four Pion Vector Meson State of Mass $\simeq{}$ 1.5 GeV Produced by Linearly Polarized 9.3 GeV Photons