We have studied natural parity states in 26 Mg via the 22 Ne( 6 Li, d) 26 Mg reaction. Our method significantly improves the energy resolution of previous experiments and, as a result, we report the observation of a natural parity state in 26 Mg. Possible spin-parity assignments are suggested on the basis of published γ -ray decay experiments. The stellar rate of the 22 Ne(α, γ ) 26 Mg reaction is reduced and may give rise to an increase in the production of s-process neutrons via the 22 Ne(α, n) 25 Mg reaction.

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Sm (25). We prepared spectroscopic alpha sources (20-100 μg) from the three activations and counted them during several months using a silicon surface-barrier detector at Kanazawa University (Fig. 1, 25 Galactic-disk enrichment in low-metallicity gas (Fig. 3). This reduces the age of late events (≥ 50 Ma) (age is measured in this work relative to the birth of the solar system) but has a minor effect on earlier events (Table 1). Samarium-146 observations in terrestrial samples can be divided into two groups: (i) most terrestrial rocks display a 142 Nd/ 144 Nd ratio higher by ~18 parts per million (ppm) than CHUR (9) and (ii) anomalies in the 142 Nd/ 144 Nd ratio relative to the terrestrial standard, both positive, in rocks from Greenland and Australia (2,10), and negative, in rocks from Northern Quebec (2,11).