ENERGY DEPENDENCE OF ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}}$ DALITZ PLOTS

2023

BES3

${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}}$

$-0.0265$ $\pm0.0010$ $\pm0.0009$

2018

CRYB

${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}}$

$-0.055$ $\pm0.014$ $\pm0.004$

33k

2015

BES3

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}}$

$-0.0301$ $\pm0.0035$ ${}^{+0.0022}_{-0.0035}$

512k

2010

KLOE

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \phi}}$ $\rightarrow$ ${{\mathit \eta}}{{\mathit \gamma}}$

$-0.027$ $\pm0.008$ $\pm0.005$

120k

ADOLPH

WASA

${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit p}}{{\mathit \eta}}$

$-0.0322$ $\pm0.0012$ $\pm0.0022$

CRYB

${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}}$

$-0.032$ $\pm0.002$ $\pm0.002$

1.8M

UNVERZAGT

CRYB

${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}}$

$-0.026$ $\pm0.010$ $\pm0.010$

75k

BASHKANOV

2007

WASA

${{\mathit p}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit p}}{{\mathit \eta}}$

$-0.010$ $\pm0.021$ $\pm0.010$

12k

ACHASOV

2001

SND

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \phi}}$ $\rightarrow$ ${{\mathit \eta}}{{\mathit \gamma}}$

$-0.031$ $\pm0.004$

TIPPENS

2001

CRYB

${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit n}}{{\mathit \eta}}$, 720 MeV

$-0.052$ $\pm0.017$ $\pm0.010$

98k

ABELE

1998

CBAR

${{\overline{\mathit p}}}$ ${{\mathit p}}$ $\rightarrow$ 5 ${{\mathit \pi}^{0}}$

$-0.022$ $\pm0.023$

50k

ALDE

1984

GAM2

• • • We do not use the following data for averages, fits, limits, etc. • • •

$-0.038$ $\pm0.003$ ${}^{+0.012}_{-0.008}$

1.34M

2008

KLOE

$-0.32$ $\pm0.37$

192

BAGLIN

1970

HLBC

¹ This ADOLPH 2009 result is independent of the BASHKANOV 2007 result.

² The PRAKHOV 2009 and UNVERZAGT 2009 results are independent.

³ This AMBROSINO 2008D value is an indirect result using ${{\mathit \eta}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{0}}{{\mathit \pi}^{-}}$ events and a$~$rescattering matrix that mixes isospin decay amplitudes.

$\alpha $ PARAMETER FOR ${{\mathit \eta}}$ $\rightarrow$ 3${{\mathit \pi}^{0}}$

References:

2023AN

PR D107 092007

Precision measurement of the matrix elements for

? ? ?^{+} ?^{-} ?^{0}

and

? ? ?^{0} ?^{0} ?^{0}

decays

2018

PR C97 065203

High-statistics measurement of the $\eta \to 3\pi^0$ decay at the Mainz Microtron

2015G

PR D92 012014

Measurement of the Matrix Elements for the Decays ${{\mathit \eta}}$ $\rightarrow$ ${+}$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ and ${{\mathit \eta}}$ $/$ ${{\mathit \eta}^{\,'}}$ $\rightarrow$ ${{\mathit \pi}^{0}}{{\mathit \pi}^{0}}{{\mathit \pi}^{0}}$

2010A

PL B694 16

Measurement of the ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$ Slope Parameter $\alpha $ with the KLOE Detector

ADOLPH

PL B677 24

Measurement of the ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$ Dalitz Plot Distribution with the WASA Detector at COSY

PR C79 035204

Measurement of the Slope Parameter $\alpha $ for the ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$ Decay with the Crystal Ball Detector at the Mainz Microtron (MAMI-C)

UNVERZAGT

EPJ A39 169

Determination of the Dalitz Plot Parameter $\alpha $ for the Decay ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$ with the Crystal Ball at MAMI-B