2-9 July 2014
Valencia, Spain
Europe/Madrid timezone

Last results of DIRAC experiment on study hadronic hydrogen-like atoms at PS CERN.

4 Jul 2014, 17:00
Sala 3+4 ()

Sala 3+4

Decision by LOC Strong Interactions and Hadron Physics Strong Interactions and Hadron Physics


Dr. Afanasyev Leonid (Joint Institute for Nuclear Research (JINR))


Results on study the hydrogen-like atoms consisting of charged pions and Kaons are presented. The first measurement of K+π− and K−π+ atoms lifetime was fulfilled basing on identification of 178±49 Kπ pairs from the atom breakup. The measured lifetime is τ=〖2.5〗_(-1.8)^(+3.0) fs . This value is dictated by properties of the strong πK-interaction at low energy, namely S-wave πK scattering length. The first experimental value of the isospin-odd combination of S-wave πK scattering length was obtained |a_0^- |=1/3|a_(1/2)-a_(3/2) |=(〖0.11〗_(-0.04)^(+0.09))M_π^(-1). A dedicated experiment with π+π− atoms allows further study of these already observed atoms. The preliminary results on observation of the long-lived (metastable) states of π+π− atoms are presented. The observation of long-lived states opens the possibility to measure the energy difference between ns and np states – the Lamb shift.

Primary author

Dr. Afanasyev Leonid (Joint Institute for Nuclear Research (JINR))

Presentation Materials


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