Using the value of beta to help determine gamma from B decays

It has been pointed out by Gronau and Rosner that the angle gamma of the un itarity triangle could be determined by combining future results on B-s and B-d decays to K pi. Here we show that it is important to include in the an alysis the information on the phase beta which will, be determined in the n ear future. Omitting this information could lead to an error as large as 8 degrees in gamma. (C) 2000 Elsevier Science B.V. All rights reserved.