Abundances of Mercury in Sirius and VEGA

Abstract

The resonance line of Hg II at 1942 Å in Sirius and Vega is analyzed quantitatively based on high-resolution UV spectroscopic data. The spectrum synthesis technique is employed. The abundance of Hg in Sirius (log ɛ(Hg) = 2.5±0.5) is found to coincide with that found in the two normal late B-type stars ν Cap and π Cet. On the other hand, the obtained upper limit for Vega (log ɛ(Hg) ≤ 0.5) is lower than the solar-system abundance log ɛ(Hg) = 1.2.