D-brane Wess-Zumino terms and U-duality

We construct gauge-invariant and U-duality covariant expressions for Wess-Zumino terms corresponding to general D p -branes (0 ≤ p ≤ D − 1) in arbitrary 3 ≤ D ≤ 10 dimensions. A distinguishing feature of these Wess-Zumino terms is that they contain twice as many scalars as the 10 − D compactified dimensions, in line with doubled geometry. We find that for D < 10 the charges of the higher-dimensional branes can all be expressed as products of the 0-brane charges, which include the D0-brane and the NS-NS 0-brane charges. We give the general expressions for these charges and show how they determine the non-trivial conjugacy class to which some of the higher-dimensional D-branes belong.