Measurement of the $\pi K$ atom lifetime and the $\pi K$ scattering length

Abstract

After having announced the statistically significant observation (5.6~$\sigma$) of the new exotic $\pi K$ atom, the DIRAC experiment at the CERN proton synchrotron presents the measurement of the corresponding atom lifetime, based on the full $\pi K$ data sample: $\tau =(5.5_{-2.8}^{+5.0})\cdot 10^{-15}s$. By means of a precise relation ($<1\%$) between atom lifetime and scattering length, the following value for the S-wave isospin-odd $\pi K$ scattering length $a_0^{-}=\frac{1}{3}(a_{1/2}-a_{3/2})$ has been derived: $\left|a_0^{-}\right|=(0.072_{-0.020}^{+0.031})M_{\pi }^{-1}$.

18 pages, 17 figures

References in corpus (3)

• Pi-K Scattering in Full QCD with Domain-Wall Valence Quarks
• First $\pi K$ atom lifetime and $\pi K$ scattering length measurements
• Direct calculation of the probability of pionium ionization in the target

Cited by in corpus (5)

• Strange Hadron Spectroscopy with Secondary KL Beam in Hall D
• Manifestation of kaonium in the $e^{+}{e}^{-}\to K^{+}{K}^{-}$ process
• Short-Range Hard-Sphere Potential and Coulomb Interaction: Deser-Trueman Formula for Rydberg States of Exotic Atomic Systems
• New method for fitting the low-energy constants in chiral perturbation theory
• Investigation of $K^{+}{K}^{-}$ pairs in the effective mass region near $2m_K$