Observational evidence points at AGB stars as possible progenitors of
  CEMP-s & r/s stars
  Origin of enhanced abundance of heavy elements observed in the surface
chemical composition of carbon-enhanced metal-poor (CEMP) stars still remain
poorly understood. Here, we present detailed abundance analysis of seven CEMP
stars based on high resolution (R${\sim}$ 50\,000) spectra that reveal enough
evidence of Asymptotic Giant Branch (AGB) stars being possible progenitors for
these objects. For the objects HE0110$-$0406, HE1425$-$2052 and HE1428$-$1950,
we present for the first time a detailed abundance analysis. Our sample is
found to consists of one metal-poor ([Fe/H]$<$$-1.0$) and six very metal-poor
([Fe/H]$<$$-2.0$) stars with enhanced carbon and neutron-capture elements. We
have critically analysed the observed abundance ratios of [O/Fe], [Sr/Ba] and
[hs/ls] and examined the possibility of AGB stars being possible progenitors.
The abundance of oxygen estimated in the programme stars are characteristics of
AGB progenitors except for HE1429$-$0551 and HE1447$+$0102. The estimated
values of [Sr/Ba] and [hs/ls] ratios also support AGB stars as possible
progenitors. The locations of the programme stars in the absolute carbon
abundance A(C) vs. [Fe/H] diagram along with the Group I objects hint at binary
nature of the object. We have studied the chemical enrichment histories of the
programme stars based on abundance ratios [Mg/C], [Sc/Mn] and [C/Cr]. Using
[C/N] and $^{12}$C/$^{13}$C ratios we have examined if any internal mixing had
modified their surface chemical compositions. Kinematic analysis shows that the
objects HE 0110$-$0406 and HE1447$+$0102 are thick disk objects and the
remaining five objects belong to the halo population of the Galaxy.
