if a fission-product decay curve of eh 2 and a 15- hour half-life for Na" 24 are assumed, then the maximum ratio of Na@4 activity occurs 26 hours after shot time, The intensities of the 2.75 Mev and 1.37 Mev lines may be extra=a af oa ——e poleted back to this time to give a maximum |“percentageNa®t | contribution.