T-odd correlation in theKl3γdecay

Abstract

The dependence of the K + → π 0 l + ν l γ decay width on the T -odd kinematical variable,3 , is studied at the tree and one-loop levels of Standard Model. It is shown that at the tree level this decay width is the even function of ξ, while the odd contribution arises due to the electromagnetic final state interaction. This contribution is determined by imaginary parts of one-loop diagrams. The calculations performed show that the ξ-odd contribution to the K + → π 0 e + ν e γ and K + → π 0 µ + ν µ γ decay widths is four orders of magnitude smaller than even contribution coming from the tree level of SM.

Radiativeβdecay for studies ofCPviolation

“…A triple momentum correlation has been previously studied in decay [60,61], for which both electromagnetic and strong radiative corrections enter, but the electromagnetic FSI effects are orders of magnitude larger [62]. The small energy release associated with neutron and nuclear radiative β decay imply that only electromagnetic radiative corrections can mimic the T-odd effect.…”

Study ofK+→π0e+νeγdecay with OKA setup

“…Reasonable agreement of the data with MC is seen. When generating the signal MC, a generator based on O(p 2 ) [9] is used.…”

Study of K^(-) into e,nu,pi^(0),gamma decay with ISTRA+ setup

“…Theoretical prediction by V.V.Braguta, A.A.Likhoded, A.E.Chalov [11], at tree level, is Br = 3.12 ×10 −4 . For the asymmetry A ξ (for the same cuts as in Table 2) we get…”

“…Bolotov At present it is the best estimate of this asymmetry. It can be compared with an upper limit on the A ξ value |A ξ (K − → π 0 e − ν e γ)| < 0.8 · 10 −4 in the SU(2) L × SU(2) R ×U(1) model [15] and A ξ = −0.59 × 10 −4 in the SM [11].…”

“…T-odd correlation vanishes at tree level in the SM [11], but the SUSY theory gives rise to CP-odd(T-odd) observables already at tree level [12,13,14]. T-odd asymmetry value for SU(2) L ×SU(2) R ×U(1) model and scalar models was estimated in [15].…”