Isobaric analog state
= Isobaric analog state
Nuclear <quantum states> in different <nuclear isobars> belonging to the same <isospin multiplet>, with equal total <isospin> and approximately the same spatial and spin structure. An <isospin> raising or lowering operator connects the states in the limit of exact isospin symmetry. <Nuclear Coulomb energy> and other isospin-breaking effects shift their <energies> and modify this ideal relationship.