One-Nanosecond Overlap Coincidence Counting to Track PET Agents over Six Decades

Residue functions track the clearance of radio-labeled substrates through key metabolic pathways. Fast positron coincidence detection (BaF2, CsF) has a millihertz benchtop background. Subnanosecond resolution is preserved by delay-trimming NIM negative logic in a three-fold overlap "AND" circuit, enabling measurements over six decades of dynamic range on isolated animal preparations.