Autori: B. Adeva, ..., M. Pentia, et al

Editorial: Phys.Lett.B, 674, p.11-16, 2009.

Rezumat:

We present evidence for the first observation of electromagnetically bound pi^+/- K^-/+ pairs (piK-atoms) with the DIRAC experiment at the CERN-PS. The piK-atoms are produced by the 24 GeV/c proton beam in a thin Pt-target and the pi^+/- and K^-/+ mesons from the atom dissociation are analyzed in a two-arm magnetic spectrometer. The observed enhancement at low relative momentum corresponds to the production of 173+/-54 piK-atoms. The mean life of piK-atoms is related to the s-wave piK-scattering lengths, the measurement of which is the goal of the experiment. From these first data we derive a lower limit for the mean life of 0.8fs at 90% confidence level.

Cuvinte cheie: DIRAC experiment, Exotic atoms, Scattering length

URL: http://dx.doi.org/10.1016/j.physletb.2009.03.001