Lithium anomaly in K giants: Connection with RGB luminosity bump
Yerra Bharat Kumar and Bacham Eswar Reddy

Indian Institute of Astrophysics, Bangalore
E-mail: bharat@iiap.res.in

Abstract. A few K giants are found to have anomalous high Li in their atmospheres. Adding to this anomaly, Li-rich K giants show far infrared excess and high rotation. Origin of overabundance of Li and associated peculiarities in Li-rich K giants are not well understood. To increase the sample size as well as to understand underlying physical process for excess Li, we have initiated spectroscopic survey of 2000 K giants along the red giant branch. This is the first major survey covering giants from RGB base to post luminosity bump in the HR~diagram. Survey resulted in 14 new Li-rich K giants increasing the total number of Li-rich K giants by a factor of two. Importantly, all the Li-rich K giants occur at the luminosity bump suggesting their connection to internal changes in the star. We discuss the survey and the consequences of the evidence that Li-rich phenomenon occurs only at a particular position on the HR diagram.