Electron Capture and Alpha Decay ofNp235

The electron capture and alpha decay of ${\mathrm{Np}}^{235}$ have been investigated. An $\frac{L}{K}$ capture ratio of 30±2 is found from absolute $L$ and $K$ x-ray measurements. No gamma rays are observed in the electron capture decay of ${\mathrm{Np}}^{235}$. An alpha branching ratio of (3.5±0.4)×${10}^{-5\mathrm{}}$ was measured for this nuclide. The alpha particles have coincident 26- and 85-kev gamma rays with an intensity of 0.054±0.005 gamma per alpha disintegration for the 85-kev gamma ray. The intensity of the 26-kev gamma ray is comparable, although somewhat more uncertain.