Spectrographically obtained zirconium, niobium and technetium abundances in a sample of low-mass stars of type S are used to determine that, in these stars, heavy elements are synthesized by the slow-neutron-capture process at a temperature of less than about 250 million kelvin, and that the process began one million to three million years ago.
- P. Neyskens
- S. Van Eck
- B. Plez
