Fig. 1: 7Be EC in an STJ.
From: Direct experimental constraints on the spatial extent of a neutrino wavepacket
Schematic of the STJ sensor showing the five layers described in the text. The 7Be radioactive source is sparsely implanted into the Ta lattice of the absorber layer. The zoomed-in image (top right) shows the final state after EC decay including 7Li recoil and νe.
