Monopole constituents inside SU(n) calorons

We present a simple result for the action density of the SU(n) charge one periodic instantons – or calorons – with arbitrary non-trivial Polyakov loop P∞ at spatial infinity. It is shown explicitly that there are n lumps inside the caloron, each of which represents a BPS monopole, their masses being related to the eigenvalues of P∞. A suitable combination of the ADHM construction and the Nahm transformation is used to obtain this result.