${{\mathit \eta}}$ MASS

INSPIRE   PDGID:
S014M
Recent measurements resolve the obvious inconsistency in previous ${{\mathit \eta}}$ mass measurements in favor of the higher value first reported by NA48 (LAI 2002). We use only precise measurements consistent with this higher mass value for our ${{\mathit \eta}}$ mass average.
VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 547.862 \pm0.017}$ OUR AVERAGE
$547.865$ $\pm0.031$ $\pm0.062$
NIKOLAEV
2014
CRYB ${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \eta}}$
$547.873$ $\pm0.005$ $\pm0.027$ 1M
GOSLAWSKI
2012
SPEC ${{\mathit d}}$ ${{\mathit p}}$ $\rightarrow$ ${}^{3}\mathrm {He}{{\mathit \eta}}$
$547.874$ $\pm0.007$ $\pm0.029$
AMBROSINO
2007B
KLOE ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \phi}}$ $\rightarrow$ ${{\mathit \eta}}{{\mathit \gamma}}$
$547.785$ $\pm0.017$ $\pm0.057$ 16k
MILLER
2007
CLEO ${{\mathit \psi}{(2S)}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \eta}}$
$547.843$ $\pm0.030$ $\pm0.041$ 1134
LAI
2002
NA48 ${{\mathit \eta}}$ $\rightarrow$ 3 ${{\mathit \pi}^{0}}$
• • We do not use the following data for averages, fits, limits, etc. • •
$547.311$ $\pm0.028$ $\pm0.032$ 1
ABDEL-BARY
2005
SPEC ${{\mathit d}}$ ${{\mathit p}}$ $\rightarrow$ ${}^{3}\mathrm {He}{{\mathit \eta}}$
$547.12$ $\pm0.06$ $\pm0.25$
KRUSCHE
1995D
SPEC ${{\mathit \gamma}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \eta}}{{\mathit p}}$, threshold
$547.30$ $\pm0.15$
PLOUIN
1992
SPEC ${{\mathit d}}$ ${{\mathit p}}$ $\rightarrow$ ${}^{3}\mathrm {He}{{\mathit \eta}}$
$547.45$ $\pm0.25$
DUANE
1974
SPEC ${{\mathit \pi}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit n}}$ neutrals
$548.2$ $\pm0.65$
FOSTER
1965C
HBC
$549.0$ $\pm0.7$ 148
FOELSCHE
1964
HBC
$548.0$ $\pm1.0$ 91
ALFF-STEINBER..
1962
HBC
$549.0$ $\pm1.2$ 53
BASTIEN
1962
HBC
1  ABDEL-BARY 2005 disagrees significantly with recent measurements of similar or better precision. See comment in the header.
References