# When a nucleus undergoes gamma decay, what happens to its atomic number?

$\text{_(28)^(60) "Ni"^"*" -> ""_(28)^(60) "Ni" + overbrace(""_(0)^(0) gamma + "1.33 MeV")^"Energy only, no mass}$
where ""_(0)^(0) gamma is a gamma ray photon, i.e. a nonrelativistically massless particle of light.