Interstellar 36 S : a probe of s - process nucleosynthesis ⋆
نویسندگان
چکیده
The first detection of a 36 S-bearing molecule in interstellar space is reported. The J=2−1 and 3−2 transitions of C 36 S have been observed toward eight Galactic molecular hot cores. From a comparison with other optically thin isotopic species of CS, the abundance ratio of 34 S/ 36 S is 115(±17). This is smaller than the solar system ratio of 200 and supports the idea that 36 S is, unlike the other stable sulfur isotopes, a purely secondary nucleus that is produced by s-process nucleosynthesis in massive stars.
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