Abstract Details
| Name: Anirban Bhowmick Affiliation: JRF- IIA Conference ID: ASI2016_717 Title : Determination of $^{16}O/^{18}O$ ratios in carbon rich hydrogen deficient stars from their infra-red spectra Authors and Co-Authors : Dr. Gajendra Pandey, Associate Professor, IIA (Indian Institute of Astrophysics) Abstract Type : Poster Abstract Category : Stars, The Milky Way Galaxy and its neighbours Abstract : The formation and evolutionary connections of carbon rich hydrogen deficient stars viz. R Coronae Borealis stars (RCBs), Hydrogen deficient Carbon stars (HdCs), DYPer and DYPer candidates are not clearly known. Till now two possible scenarios have been proposed for the formation and evolution of these stars: 1) Merging of two white dwarfs and 2) Final Helium shell flash in a post AGB (Asymptotic Giant Branch) star. Till date in some of the known RCB/HdC stars the $^{16}O/^{18}O$ ratios are observed to be very low whereas $^{16}O/^{18}O$ in the solar neighbourhood is $\sim$ 500. Thus the $^{16}O/^{18}O$ ratios are one of the potential clues for determining their formation and evolutionary scenario. Hence we observationally investigate low resolution (R $\sim$ 1200) H and K band spectras of a group of RCBs, HdCs and DYPer and DYPer candidates using TIRSPEC on HCT 2m telescope, Hanle, to look for the near IR transitions of CO and its isotopes for determining $^{16}O/^{18}O$ ratios. |