If Lorentz and CPT violation exist, they could affect the decays of scalar and pseudoscalar particles. For a decay into a fermion and an antifermion (not necessarily of the same mass), both the total decay rate and the outgoing particle distribution may be modified, through interference between the conventional decay mechanism and a separate Lorentz-violating mechanism. The modifications are sensitive to forms of Lorentz violation that are otherwise rather difficult to study, since at tree level they do not affect particle propagation, but only interaction vertices. Using existing experimental data on charged pion decay, it is possible to constrain three parameters in the modified pionmuon-neutrino coupling at better than the 10−9 level; these are the first bounds on these quantities.
Digital Object Identifier (DOI)
Physical Review D, Volume 89, Issue 11, 2014.
© 2014 American Physical Society
Altschul, B. (2014). Lorentz violation in fermion-antifermion decays of spinless particles. Physical Review D, 89(11). https://doi.org/10.1103/physrevd.89.116007