# Function crpropa::nucleusId¶

## Function Documentation¶

int nucleusId(int a, int z)

This implements the 2012 Monte Carlo nuclear code scheme. Ion numbers are +/- 10LZZZAAAI. AAA is A - total baryon number ZZZ is Z - total charge L is the total number of strange quarks. I is the isomer number, with I=0 corresponding to the ground state.