What highly ionised elements are found in the spectrum of WR 102c?
Wolf–Rayet star Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectra showing prominent broad emission lines of highly ionised helium and nitrogen or carbon. The spectra indicate very high surface enhancement of heavy elements, depletion of hydrogen, and strong stellar winds. Their surface temperatures range from 30,000 K to around 200,000 K, hotter than almost all other stars.
Isotopes of barium Naturally occurring barium (Ba) is a mix of six stable isotopes and one very long-lived radioactive primordial isotope, barium-130, recently identified as being unstable by geochemical means (from analysis of the presence of its daughter xenon-130 in rocks). This nuclide decays by double-electron capture (absorbing two electrons and emitting two neutrons); with a half-life of (0.5–2.7)×10 years (about 10 times the age of the universe).