A special class of solutions to the generalised WDVV equations related to a finite set of covectors is investigated. Some geometric conditions on such a set which guarantee that the corresponding function satisfies WDVV equations are found (boolean OR-conditions). These conditions are satisfied for all root systems and their special deformations discovered in the theory of the Calogero-Moser systems by Chalykh, Feigin and the author. This leads to the new solutions for the generalized WDVV equations.
This is a pre-print. The definitive version: VESELOV, A.P., 1999. Deformations of the root systems and new solutions to generalised WDVV equations. Physics Letters A, 261(5-6), pp. 297-302, is available at: http://www.sciencedirect.com/science/journal/03759601.