We report on a high-resolution spectroscopic stellar parameter and abundance analysis of a d ^ { { } ^ { \prime } } symbiotic star : the yellow component of StH \alpha 190 .
This star has recently been discovered , and confirmed here , to be a rapidly rotating ( v sini = 100 \pm 10 km s ^ { -1 } ) subgiant , or giant , that exhibts radial-velocity variations of probably at least 40 km s ^ { -1 } , indicating the presence of a companion ( as in many symbiotic systems , the companion is a hot white-dwarf star ) .
An analysis of the red spectrum reveals the cool stellar component to have an effective temperature of T _ { eff } =5300 \pm 150K and a surface gravity of log g = 3.0 \pm 0.5 ( this corresponds to an approximate spectral type of G4III/IV ) .
These parameters result in an estimated primary luminosity of 45L _ { \odot } , implying a distance of about 780 pc ( within a factor of 2 ) .
The iron and calcium abundances are found to be close to solar , however , barium is overabundant , relative to Fe and Ca , by about +0.5 dex .
The Ba enhancement reflects mass-transfer of s-process enriched material when the current white dwarf was an asymptotic giant branch ( AGB ) star , of large physical dimension ( \geq 1AU ) .
The past and future evolution of this binary system depends critically on its current orbital period , which is not yet known .
Concerted and frequent radial-velocity meassurements are needed to provide crucial physical constraints to this d ’ symbiotic system .