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Paper text:
symbiotic stars are long - period binary systems composed of two evolved and strongly interacting stars : a red giant donor and a hot luminous white dwarf companion ( occasionally replaced by a neutron star ) surrounded by an ionized nebula .
mass exchange between the binary system members is critical in defining their evolution .
mass - loss from the giant undergoes accretion to the compact object via wind and@xmath1or roche lobe overflow ( @xcite , @xcite ) resulting in the formation of an accretion disc and jet ( @xcite , @xcite , @xcite ) .
the hot companion had previously passed through a red giant stage . in the previous red giant stage mass
was transferred from this star to the star that is currently a red giant .
abundance signatures tracing this mass transfer process have been measured in some red giant  white dwarf binary systems @xcite . in some cases
the mass transfer process can result in symbiotic progenitors for supernovea type ia ( sneia ) .
symbiotic systems are believed responsible for between a few per cent to 30 per cent of sneia events ( @xcite , @xcite ) .
knowledge of the elemental abundances of symbiotic giants is essential to address the role of chemical composition in the evolution of symbiotic binaries , to map their parent population , and to trace their mass transfer history . 
 however , there are few symbiotic giants for which the photospheric abundances are fairly well determined . 
 this is the second in a series of papers on chemical composition of symbiotic giants determined from high - resolution ( r@xmath050000 ) near - ir spectra . 
 results are presented for the late - type giant star in the aeara , bxmon , kxtra , and clsco systems . 
 spectrum synthesis employing standard local thermal equilibrium ( lte ) analysis and stellar atmosphere models were used to obtain photospheric abundances of cno and elements around the iron peak ( sc , ti , fe , and ni ) . 
 our analysis resulted in sub - solar metallicities in bxmon , kxtra , and clsco by [ fe@xmath1h]@xmath2 or @xmath3 depending on the value of microturbulence . 
 aeara shows metallicity closer to solar by @xmath4dex . 
 the enrichment in @xmath5n isotope found in all these objects indicates that the giants have experienced the first dredge - up . in the case of bxmon first dredge - up 
 is also confirmed by the low @xmath6c/@xmath7c isotopic ratio of @xmath08 .    
 [ firstpage ]    stars : abundances  stars : atmospheres  binaries : symbiotic  stars : individual : ae ara , bx mon , kx tra , cl sco  stars : late - type