pdgLive

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

INSPIRE JSON (beta) PDGID:

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.

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