International Conference on Precision Physics and Fundamental Physical Constants (FFK-2015)

Observation of long-lived states of hydrogen-like atom consisting of pi+ and pi- mesons.

13 Oct 2015, 11:00

45m

Kis terem (Small conference room) (Hungarian Academy of Sciences)

Exotic Atoms -1

Speaker

Leonid Afanasyev (Joint Inst. for Nuclear Research (RU))

Description

DIRAC experiment at the CERN PS accelerator observes for the first time long-lived states of hydrogen-like atom consisting of $\pi^+$ and $\pi^-$ mesons with lifetimes of about 10−11~s and more. There were observed $436\pm61$ characteristic pion pairs resulting from the long-lived states breakup, that corresponds to a signal-to-error ratio of better than 7 standard deviations. Together with measurement of the ground state lifetime of $\pi^+\pi^-$ atom, this observation opens a new possibility for detailed study of $\pi\pi$ scattering lengths.

Presentation materials

Afanasyev_FFK-2015.pdf