We have measured the electron-capture decay branch of Tc to be (1.8 + 0.9) x 10 %, from which we deduce log ft = 4.45+o'so. This indicates that a two-step process connecting only the ground states of ' Mo-' Tc-Ru can account for the measured 2v double-P-decay rate of Mo.PACS number(s): 23.40.s, 23.40.Bw, 24.80.Ba, 24.80.x

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We present the results of two separate measurements of the half-life of 44 Ti relative to those of 22 Na and 207 Bi, respectively. By comparing the numbers of 1157-keV ␥ rays from 44 Ti to those of 1274-keV ␥ rays from 22 Na observed from a mixed source over a period of approximately 2 yr, we determined the half-life of 44 Ti to be 61.5Ϯ1.0 yr. From an approximately 1-yr-long study of another mixed source, where we compared the numbers of 1157-keV ␥ rays from 44 Ti to those of 1064-keV ␥ rays from 207 Bi, we determined the 44 Ti half-life to be 62Ϯ5 yr. From these two results, we have obtained a best value of 62Ϯ2 yr for the half-life of 44 Ti. The astrophysical implications of this result are discussed.

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