Jul 16 – 22, 2009
Kraków, Poland
Europe/Warsaw timezone

Experimental evidence for piK-atoms

Jul 17, 2009, 5:25 PM
Exhibition room B (Kraków, Poland)

Exhibition room B

Kraków, Poland

The Auditorium Maximum of the Jagiellonian University 33 Krupnicza Street 31-123 Kraków
QCD in hadronic physics VI. QCD in Hadronic Physics


Prof. Claude Amsler (University of Zurich)


We present evidence for the first observation of electromagnetically bound pion-kaon pairs (piK- atoms) with the DIRAC-II experiment at the CERN-PS. The mean life of piK-atoms is related to the s-wave piK-scattering lengths, a measurement of which is relevant to low energy QCD, in particular chiral perturbation theories including the s-quarks. The atoms are produced by a 24 GeV/c proton beam in a thin Pt-target and the dissociated pions and kaons analyzed in a two-arm magnetic spectrometer. The observed enhancement at low relative momentum corresponds to the production of 173 +- 54 piK-atoms. From these first data we derive a lower limit for the mean life of 0.8 fs at the 90% confidence level.

Primary author

Prof. Claude Amsler (University of Zurich)

Presentation materials