Experimental evidence for πK-atoms
نویسنده
چکیده
Electromagnetically bound π±K∓-pairs (πK-atoms) have been observed by the DIRAC-II experiment at the CERN-PS. The πK-atoms were produced by the 24 GeV/c proton beam impinging on a thin Pt-target. The π±and K∓-mesons from the atom dissociation were analyzed in a two-arm magnetic spectrometer. An enhancement was observed at low relative momentum, corresponding to the production of 173 ± 54 πK-atoms. From these first data a lower limit for the mean life of 0.8 fs was derived at the 90% confidence level. The mean life being related to the S-wave πK-scattering lengths a1 and a3 in the isospin 1/2 and 3/2 states, one then obtains an upper limit for the difference |a1−a3| of 0.58 m−1 π at the 90% confidence level.
منابع مشابه
Evidence for πK-atoms with DIRAC
We present evidence for the rst observation of electromagnetically bound π±K∓pairs (πK-atoms) with the DIRAC experiment at the CERN-PS. The πK-atoms are produced by the 24 GeV/c proton beam in a thin Pt-target and the π± 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 ...
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