Transverse Polarization in the Beta Decay of Tm170

In a series of experiments a careful attempt has been made to measure the transverse polarization of the $\ensuremath{\beta}$ particles in the 883-keV ($logft=9.3$) transition in ${\mathrm{Tm}}^{170}$. Mott-scattering techniques were used to detect the $\ensuremath{\beta}$ polarization. The study shows that transverse-polarization measurements do not appear to be a fruitful way to delimit the matrix elements of transitions unless perhaps there is a marked deviation from the $\ensuremath{\xi}$-approximation calculations. The experimental value for the transverse polarization in the plane defined by the emitted $\ensuremath{\beta}$ and $\ensuremath{\gamma}$ particles, ${P}_{\mathrm{II}}=\ensuremath{-}0.024\ifmmode\pm\else\textpm\fi{}0.015$, is consistent with calculations from matrix elements satisfying the $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ directional correlation coefficient and shape-correction factor.