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All the elements heavier than Fe are produced either by slow (-s) or rapid(-r) neutron-capture process. Neutron density prevailing in the stellar sitesis one of the major factors that determines the type of neutron-captureprocesses. We present the results based on the estimates of corrected value ofabsolute carbon abundance, [C/N] ratio, carbon isotopic ratio and [hs/ls] ratioobtained from the high resolution spectral analysis of six stars that includeboth CH stars and CEMP stars. All the stars show enhancement of neutron-captureelements. Location of these objects in the A(C) vs. [Fe/H] diagram shows thatthey are Group I objects, with external origin of carbon and neutron-captureelements. Low values of carbon isotopic ratios estimated for these objects mayalso be attributed to some external sources. As the carbon isotopic ratio is agood indicator of mixing, we have used the estimates of 12C/13C ratios toexamine the occurance of mixing in the stars. While the object HD 30443 mighthave experienced an extra mixing process that usually occurs after red giantbranch (RGB) bump for stars with log(L/L0) > 2.0, the remaining objects do notshow any evidence of having undergone any such mixing process. The highervalues of [C/N] ratios obtained for these objects also indicate that none ofthese objects have experienced any strong internal mixing processes. Based onthe estimated abundances of carbon and the neutron-capture elements, and theabundance ratios, we have classified the objects into different groups. Whilethe objects HE 0110-0406, HD 30443 and CD-38 2151 are found to be CEMP-s stars,HE 0308-1612 and HD 176021 show characteristic properties of CH stars withmoderate enhancement of carbon. The object CD-28 1082 with enhancement of bothr- and s-process elements is found to belong to the CEMP-r/s group.

Abundances of neutron-capture elements in CH and Carbon-Enhanced Metal-Poor (CEMP) stars