 2

For the complex scalar fields, use the conventional particle names: $\varphi$ annihilates a light $\varphi$ particle and creates a light antiparticle $\bar{\varphi }$; $\Phi$ annihilates a heavy $\Phi$ particle and creates $\bar{\Phi }$. These choices make the distinction between particle labels and field symbols explicit throughout ii and iii. The couplings $g,h$ are real as required by the printed Hermitian Lagrangian density.