October 2003 - h. 15:00
Observation of New
Narrow Ds states
The BaBar experiment has discovered a new narrow state, Ds(2317), near
2.32 GeV in the inclusive Ds pi0 invariant mass distribution
from e+e- annihilation data at energies near 10.6 GeV.
The same experiment has also shown evidence for structure in the 2.46
GeV region in the Ds pi0 gamma mass spectrum.
These discoveries have triggered several experiments in a search for
new states coupled to the Ds meson which confirmed the existence of
Ds(2317) together with Ds(2458) both in inclusive e+ e- annihilation
and in B decays.
These two new states are difficult to explain in terms of potential