A Precision determination of the mass of the eta meson

Several processes of meson production in proton-deuteron collisions have been measured simultaneously using a calibrated magnetic spectrograph. Among these processes, the

\eta

meson is seen clearly as a sharp missing--mass peak on a slowly varying background in the

p+d\to ^3\textrm{He} +X

reaction. Knowing the kinematics of the other reactions with well determined masses, it is possible to deduce a precise mass for the

\eta

meson. The final result,

m(\eta)=547.311\pm 0.028 \textrm{(stat)} \pm 0.032 \textrm{(syst) MeV/c}^2

, is significantly lower than that found by the recent NA48 measurement, though it is consistent with values obtained in earlier counter experiments.

14.40.Aq
13.75.-n
Eta meson production
Meson mass
p deuteron: nuclear reaction
mass spectrum: missing-mass
eta: hadroproduction
eta: mass
p p: exclusive reaction
pi+: hadroproduction

References(8)

Figures(0)

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