Speaker
Description
Exotic hadronic atoms are a valuable tool to experimentally investigate the
strong interaction described by Quantum Chromodynamics (QCD). With kaonic
hydrogen/deuterium atoms one can directly measure the interaction at threshold and
will be able to extract the antikaon-nucleon scattering lengths at zero energy (no
interpolation to zero energy is necessary as in scattering experiments). The antikaon-
nucleon interaction close to threshold provides crucial information on the interplay
between spontaneous and explicit chiral symmetry breaking in low-energy QCD.
Kaonic hydrogen was measured successfully with SIDDHARTA and DEAR at
DAFNE (LNF, Italy) and with KpX at KEK (Japan). A measurement of kaonic
deuterium is still missing and just now ongoing at DAFNE. A second measurement
with different systematic corrections is prepared at J-PARC. The kaonic deuterium
data will allow for the first time, together with the already existing kaonic hydrogen
data, the determination of the isospin dependent antikaon-nucleon scattering lengths
a0 and a1, eagerly awaited by theory.
An overview of the status of the proposed kaonic deuterium measurement at
J-PARC will be given.