Isospin fluctuations from a thermally equilibrated hadron gas

Partition functions, multiplicity distributions, and isospin fluctuations are calculated for canonical ensembles in which additive quantum numbers as well as total isospin are strictly conserved. When properly accounting for Bose-Einstein symmetrization, the multiplicity distributions of neutral pions in a hadronic gas are significantly broader as compared to the nondegenerate case. Inclusion of resonances compensates for this broadening effect. Recursion relations are derived, which allow calculation of exact results with modest computer time.