POLARIZATION IN ${{\mathit B}}$ DECAY

In decays involving two vector mesons, one can distinguish among the states in which meson polarizations are both longitudinal ($\mathit L$) or both are transverse and parallel ($\parallel$) or perpendicular ($\perp$) to each other with the parameters $\Gamma _{L}/\Gamma $, $\Gamma _{}/\Gamma $, and the relative phases $\phi _{\parallel}$ and $\phi _{\perp}$. See the definitions in the note on “Polarization in ${{\mathit B}}$ Decays” review in the ${{\mathit B}^{0}}$ Particle Listings.

A${}^{(2)}_{T}$ in ${{\mathit B}}$ $\rightarrow$ ${{\mathit K}^{*}}{{\mathit e}^{+}}{{\mathit e}^{-}}$ (at low q${}^{2}$)

INSPIRE   JSON  (beta) PDGID:
S049A20
VALUE DOCUMENT ID TECN  COMMENT
$0.52$ $\pm0.53$ $\pm0.11$ 1, 2
FERLEWICZ
2024
BELL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$
1  Events are reconstructed in ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit K}^{*0}}$ ( $\rightarrow$ ${{\mathit K}^{+}}{{\mathit \pi}^{-}}$ ) ${{\mathit e}^{+}}{{\mathit e}^{-}}$ and ${{\mathit B}^{+}}$ $\rightarrow$ ${{\mathit K}^{*+}}$ ( $\rightarrow$ ${{\mathit K}_S^0}$ ${{\mathit \pi}^{+}}$ ) ${{\mathit e}^{+}}{{\mathit e}^{-}}$ decay modes. The effective dielectron invariant mass is required to be in the range 0.0008 $<$ q${}^{2}$ $<$ 1.12 GeV${}^{2}$/c${}^{4}$.
2  A${}^{Im}_{T}$ and A${}^{(2)}_{T}$ measure the ratio of the right- and left-handed Wilson coefficients, C${}^{'}_{7}/C_{7}$, which constrains non-SM contributions at small q${}^{2}$.
References