LAMOST/HRS spectroscopic analysis of two new Li-rich giants

作者：Ze-Ming Zhou,Jian-Rong Shi,Hong-Liang Yan,Yong-Hui Hou,Kai Zhang,Qi Gao,Xiao-Dong Xu,Hai-Long Yuan,Yu-Tao Zhou,Kaike Pan,Zi-Ye Sang,Yong-Heng Zhao

摘要：Two Li-rich candidates,TYC 1338-1410-1 and TYC 2825-596-1,were observed by the new high-resolution echelle spectrograph,LAMOST/HRS.Based on their high-resolution and high-signal-tonoise ratio(SNR)spectra,we derived stellar parameters and abundances of 14 important elements for the two candidates.The stellar parameters and lithium abundances indicate that they are Li-rich K-type giants,and having A(Li)NLTE and 2.91 dex,respectively.Our analysis suggests that TYC 1338-1410-1 is probably a red giant branch(RGB)star at the bump stage,while TYC 2825-596-1 is most likely to be a core helium-burning red clump(RC)star.The line profiles of both spectra indicate that the two Li-rich giants are slow rotators and do not show infrared(IR)excess.We conclude that engulfment is not the lithium enrichment mechanism for either star.The enriched lithium of TYC 1338-1410-1 could be created via the Cameron-Fowler mechanism,while the lithium excess in TYC 2825-596-1 could be associated with either non-canonical mixing processes or He-flash.

发文机构：CAS Key Laboratory of Optical Astronomy School of Astronomy and Space Science Nanjing Institute of Astronomical Optics&Technology Department of Astronomy Kavli Institute for Astronomy and Astrophysics Apache Point Observatory Astronomy Department

关键词：stars:fundamentalparametersstars:late-typestars:low-massstars:abundancesstars:chemicallypeculiar

分类号： P15[天文地球—天文学]