Hi All, Does used radiaoactivity amount" affect linearly total computation time? Best regards, Sebnem& Giacomo -- Sebnem Erturk University of Pisa Applied Physics Dpt. Largo Pontecorvo 56127 Pisa-Italy Office :0039 050 2214346 Mobile :0039 345 3331440 http://www.df.unipi.it/~fiig/