SOLITONS IN THE HORAVA-WITTEN SUPERGRAVITY

We study classical BPS five-brane solutions in the Horava-Witten super gravity. The presence of the eleventh dimension add a new feature, nam ely the dependence of the solution on this new coordinate. For gauge f ive-branes with an instanton size less than the eleventh radius and in the neighborhood of the center of the neutral five-brane, important c orrections to the ten-dimensional solution appear for all values of th e string coupling constant. We compute the mass and magnetic charge of the five-brane solitons and the result is shown to agree with the mem brane and five-brane quantization conditions. Compactified to four dim ensions, our solutions are interpreted as axionic strings. (C) 1998 El sevier Science B.V.