TWISTING CLASSICAL-SOLUTIONS IN HETEROTIC STRING THEORY

We show that, given a classical solution of the heterotic string theory which is independent of d of the space-time directions, and for which the gauge-field configuration lies in a subgroup that commutes with p of the U(1) generators of the gauge group, there is an O(d) x O(d + p) transformation, which, acting on the solution, generates new classical solutions of the theory. With the help of these transformations we construct black six-brane solutions in ten-dimensional heterotic string theory carrying independent magnetic, electric and antisymmetric tensor gauge-field charge, by starting from a black six-brane solution that carries magnetic charge but no electric or antisymmetric tensor gauge-field charge. The electric and the magnetic charges point in different directions in the gauge group.