${{\mathit \rho}{(770)}}$ MASS

We no longer list ${\mathit S}{\mathrm -wave}$ Breit-Wigner fits, or data with high combinatorial background.

NEUTRAL ONLY, ${{\mathit e}^{+}}{{\mathit e}^{-}}$

INSPIRE   JSON  (beta) PDGID:
M009M0
VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 775.26 \pm0.23}$ OUR AVERAGE
$775.3$ $\pm0.5$ $\pm0.6$ 1
ACHASOV
2021
SND ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$775.02$ $\pm0.35$ 2
LEES
2012G
 BABR ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \gamma}}$
$775.97$ $\pm0.46$ $\pm0.70$ 900k 3
AKHMETSHIN
2007
${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$774.6$ $\pm0.4$ $\pm0.5$ 800k 4, 5
ACHASOV
2006
SND ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$775.65$ $\pm0.64$ $\pm0.50$ 114k 6, 7
AKHMETSHIN
2004
CMD2 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$775.9$ $\pm0.5$ $\pm0.5$ 1.98M 8
ALOISIO
2003
KLOE 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$775.8$ $\pm0.9$ $\pm2.0$ 500k 8
ACHASOV
2002
SND 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$775.9$ $\pm1.1$ 9
BARKOV
1985
OLYA ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
• • We do not use the following data for averages, fits, limits, etc. • •
$775.4$ $\pm0.1$ 34M 10
IGNATOV
2024
CMD3 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$763.49$ $\pm0.53$ 11
BARTOS
2017
RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$758.23$ $\pm0.46$ 12
BARTOS
2017A
 RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$775.8$ $\pm0.5$ $\pm0.3$ 1.98M 13
ALOISIO
2003
KLOE 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$775.9$ $\pm0.6$ $\pm0.5$ 1.98M 14
ALOISIO
2003
KLOE 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$775.0$ $\pm0.6$ $\pm1.1$ 500k 15
ACHASOV
2002
SND 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$775.1$ $\pm0.7$ $\pm5.3$ 16
BENAYOUN
1998
RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$, ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$
$770.5$ $\pm1.9$ $\pm5.1$ 17
GARDNER
1998
RVUE $0.28 - 0.92$ ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$764.1$ $\pm0.7$ 18
O'CONNELL
1997
RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$757.5$ $\pm1.5$ 19
BERNICHA
1994
RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
$768$ $\pm1$ 20
GESHKENBEIN
1989
RVUE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$
1  From a fit of the cross section in the energy range 0.525 $<$ $\sqrt {s }$ $<$ 0.883 GeV parameterized by the sum of the Breit-Wigner amplitudes for the ${{\mathit \rho}{(770)}}$, ${{\mathit \omega}}$ and ${{\mathit \rho}{(1450)}}$ resonances.
2  Using the GOUNARIS 1968 parametrization with the complex phase of the ${{\mathit \rho}}−{{\mathit \omega}}$ interference and leaving the masses and widths of the ${{\mathit \rho}{(1450)}}$, ${{\mathit \rho}{(1700)}}$, and ${{\mathit \rho}{(2150)}}$ resonances as free parameters of the fit.
3  A combined fit of AKHMETSHIN 2007, AULCHENKO 2006, and AULCHENKO 2005.
4  Supersedes ACHASOV 2005A.
5  A fit of the SND data from 400 to 1000 MeV using parameters of the ${{\mathit \rho}{(1450)}}$ and ${{\mathit \rho}{(1700)}}$ from a fit of the data of BARKOV 1985, BISELLO 1989 and ANDERSON 2000A.
6  Using the GOUNARIS 1968 parametrization with the complex phase of the ${{\mathit \rho}}-{{\mathit \omega}}$ interference.
7  Update of AKHMETSHIN 2002.
8  Assuming ${\mathit m}_{{{\mathit \rho}^{+}}}$ = ${\mathit m}_{{{\mathit \rho}^{-}}}$, $\Gamma _{{{\mathit \rho}^{+}}}$ = $\Gamma _{{{\mathit \rho}^{-}}}$.
9  From the GOUNARIS 1968 parametrization of the pion form factor.
10  From a fit of the pion form factor in the energy range 0.32 $<$ $\sqrt {s }$ $<$ 1.2 GeV using the GOUNARIS 1968 parametrization with the complex phase of the ${{\mathit \rho}}−{{\mathit \omega}}$ interference with ${{\mathit \omega}}$ and ${{\mathit \phi}}$ masses and widths constrained by the values and their errors from PDG 2022, and leaving ${{\mathit \rho}{(1450)}}$, ${{\mathit \rho}{(1700)}}$ resonances as free parameters of the fit. Systematic errors not estimated.
11  Applies the Unitary $\&$ Analytic Model of the pion electromagnetic form factor of DUBNICKA 2010 to analyze the data of LEES 2012G and ABLIKIM 2016C.
12  Applies the Unitary $\&$ Analytic Model of the pion electromagnetic form factor of DUBNICKA 2010 to analyze the data of ACHASOV 2006, AKHMETSHIN 2007, AUBERT 2009AS, and AMBROSINO 2011A.
13  Assuming ${\mathit m}_{{{\mathit \rho}^{+}}}$ = ${\mathit m}_{{{\mathit \rho}^{-}}}$ = ${\mathit m}_{{{\mathit \rho}^{0}}}$, $\Gamma _{{{\mathit \rho}^{+}}}$ = $\Gamma _{{{\mathit \rho}^{-}}}$ = $\Gamma _{{{\mathit \rho}^{0}}}$.
14  Without limitations on masses and widths.
15  Assuming ${\mathit m}_{{{\mathit \rho}^{0}}}$ = ${\mathit m}_{{{\mathit \rho}^{\pm}}}$, $\mathit g_{{{\mathit \rho}^{0}} {{\mathit \pi}} {{\mathit \pi}}}$ = $\mathit g_{{{\mathit \rho}^{\pm}} {{\mathit \pi}} {{\mathit \pi}}}$.
16  Using the data of BARKOV 1985 in the hidden local symmetry model.
17  From the fit to ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ data from the compilations of HEYN 1981 and BARKOV 1985, including the GOUNARIS 1968 parametrization of the pion form factor.
18  A fit of BARKOV 1985 data assuming the direct ${{\mathit \omega}}{{\mathit \pi}}{{\mathit \pi}}$ coupling.
19  Applying the S-matrix formalism to the BARKOV 1985 data.
20  Includes BARKOV 1985 data. Model-dependent width definition.
References