pdgLive

${{\mathit K}^{0}}$ MASS

VALUE (MeV)

EVTS

DOCUMENT ID

TECN

COMMENT

$\bf{ 497.611 \pm0.013}$

OUR FIT Error includes scale factor of 1.2.

$\bf{ 497.611 \pm0.013}$

OUR AVERAGE Error includes scale factor of 1.2.

$497.607$ $\pm0.007$ $\pm0.015$

261k

${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit K}_S^0}$ ${{\mathit X}}$

$497.583$ $\pm0.005$ $\pm0.020$

35k

KLOE

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit K}_L^0}$ ${{\mathit K}_S^0}$

$497.625$ $\pm0.001$ $\pm0.031$

655k

NA48

${{\mathit K}_L^0}$ beam

$497.661$ $\pm0.033$

3713

CMD

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit K}_L^0}$ ${{\mathit K}_S^0}$

$497.742$ $\pm0.085$

780

CMD

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit K}_L^0}$ ${{\mathit K}_S^0}$

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

$497.44$ $\pm0.50$

OSPK

$498.9$ $\pm0.5$

4500

HBC

${{\mathit K}^{0}}$ from ${{\overline{\mathit p}}}{{\mathit p}}$

$497.44$ $\pm0.33$

2223

HBC

${{\mathit K}^{0}}$ from ${{\overline{\mathit p}}}{{\mathit p}}$

$498.1$ $\pm0.4$

OSPK

¹	Obtained by analyzing CLEO-c data but not authored by the CLEO Collaboration.

References:

PR D89 031501

High Precision Measurement of the Masses of the ${{\mathit D}^{0}}$ and ${{\mathit K}_S^0}$ mesons

JHEP 0712 073

Precise Measurements of the ${{\mathit \eta}}$ Meson and the Neutral Kaon Masses with the KLOE Detector

PL B533 196

New Measurements of the ${{\mathit \eta}}$ and ${{\mathit K}^{0}}$ Masses

SJNP 46 630

The Precision Neutral Kaon Mass Measurement

JETPL 42 138

Measurement of the Neutral Kaon Mass

PR 164 1711

Studies of ${{\mathit K}_{{2}}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Decay and Interference

PR 142 932

Study of Antiproton Proton Annihilations into ${{\mathit K}}$ and ${{\mathit \pi}}$ Mesons at 3.7 ${\mathrm {GeV/}}\mathit c$

PR 140 B1334

Measurement of the ${{\mathit K}^{0}}$ Mass and the ${{\mathit K}^{0}}{{\mathit K}^{-}}$ Mass Difference

PRL 13 138

Evidence for the 2${{\mathit \pi}}$ Decay of the ${{\mathit K}_L^0}$ Meson

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