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Related papers: Spectroscopic study of two new super Li rich red c…

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In this paper we report two new super Li-rich K giants: KIC 2305930 and KIC 12645107 with Li abundances exceeding that of ISM (A(Li) $\geq$ 3.2 dex). Importantly, both the giants have been classified as core He-burning red clump stars based…

Solar and Stellar Astrophysics · Physics 2018-05-23 Yerra Bharat Kumar , Raghubar Singh , B. Eswar Reddy , Gang Zhao

Two Li-rich candidates, TYC 1338-1410-1 and TYC 2825-596-1, were observed with the new high-resolution echelle spectrograph, LAMOST/HRS. Based on the high-resolution and high-signal-to-noise ratio (SNR) spectra, we derived stellar…

Solar and Stellar Astrophysics · Physics 2021-02-10 Zeming Zhou , Jianrong Shi , Hongliang Yan , Yonghui Hou , Kai Zhang , Qi Gao , Xiaodong Xu , Hailong Yuan , Yutao Zhou , Kaike Pan , Ziye Sang , Yongheng Zhao

In this letter, we report the discovery of 24 new super Li-rich (A(Li) $\ge$ 3.2) giants of He-core burning phase at red clump region. Results are based on systematic search of a large sample of about 12,500 giants common to the LAMOST…

Solar and Stellar Astrophysics · Physics 2019-06-19 Raghubar Singh , Bacham E. Reddy , Yerra Bharat Kumar , H. M. Antia

Given the implications for the origin of Li enhancement in red giants we have reviewed Li-rich classification of KIC~9821622, the only bonafide RGB giant with He inert-core till date, reported as a Li-rich giant by reanalyzing the…

Solar and Stellar Astrophysics · Physics 2020-01-08 Raghubar Singh , Bharat Kumar Yerra , Bacham E. Reddy , Wako Aoki

To understand the underlying mechanisms for high lithium abundances among core He-burning or red clump (RC) giants, we analyzed a sample of 5227 RC giants of mass M $\leq$ 2~M$_{\odot}$ using spectra and asteroseismic data. We found 120 RC…

Solar and Stellar Astrophysics · Physics 2025-08-06 Raghubar Singh , Bacham E. Reddy , Anohita Mallick , Gang Zhao

Aims: We report the discovery of a young lithium rich giant, HD 16771, in the core-helium burning phase that does not seem to fit existing proposals of Li synthesis near the luminosity function bump or during He-core flash. We aim to…

Solar and Stellar Astrophysics · Physics 2016-04-13 Arumalla B. S. Reddy , David L. Lambert

We present a study of correlations between high Li abundances and strong chromospheric He I 10830 \AA\ absorption line strengths in Kepler field giant stars. Our sample includes 84 giants with detectable solar-like oscillations in their…

Solar and Stellar Astrophysics · Physics 2025-01-16 Anohita Mallick , Christopher Sneden , Bacham E. Reddy , Melike Afşar

This paper presents results from Kepler photometric light curves and high-resolution spectroscopic study of a super Li-rich giant KIC11087027. Using the light curve analysis, we measured the star's rotational period P$_{\rm…

Solar and Stellar Astrophysics · Physics 2024-08-13 Raghubar Singh , Anohita Mallick , Bacham E. Reddy , Jeewan C. Pandey , Gang Zhao

It has recently been suggested that all giant stars with mass below 2 $M_{\odot}$ suffer an episode of surface lithium enrichment between the tip of the red giant branch (RGB) and the red clump (RC). We test if the above result can be…

In this Letter, we report on a low-resolution spectroscopic survey for Li-rich K giants among 2000 low mass (M <= 3 Msun) giants spanning the luminosity range from below to above the luminosity of the clump. Fifteen new Li-rich giants…

Solar and Stellar Astrophysics · Physics 2015-05-27 Yerra Bharat Kumar , Bacham E. Reddy , David L. Lambert

With an aim to shed light on the origin of Li anomaly observed in a small fraction of red giants, we carried out a spectroscopic study on the observational characteristics of selected 20 bright Li-rich giants, in comparison with a large…

Solar and Stellar Astrophysics · Physics 2017-09-20 Yoichi Takeda , Akito Tajitsu

Lithium abundances for red giants in the GALAH DR3 survey are studied. The rare examples of Li-enriched stars with abundances A(Li) $\geq 1.5$ are confirmed to be He-core burning stars belonging to or evolved from the red clump with similar…

Solar and Stellar Astrophysics · Physics 2021-08-25 Deepak , David L. Lambert

The discovery of Li-rich giant has cast a new challenge for the standard stellar evolution models, and to resolve this issue, the number of this type object has been rapidly increased because of the development of worldwide surveys these…

Solar and Stellar Astrophysics · Physics 2019-06-05 Yutao Zhou , Hongliang Yan , Jianrong Shi , S. Blanco-Cuaresma , Qi Gao , K. Pan , Xiaodong Xu , Junbo Zhang , Gang Zhao

Results from high resolution spectroscopic analysis of HD 77361 are reported. The LTE analysis shows that HD 77361 is a K giant of atmospheric parameters: Teff = 4580 +/- 75 K, log$g$ = 2.5 +/- 0.1, and \xi_{t} = 1.40 +/-0.5 km/s. We found…

Solar and Stellar Astrophysics · Physics 2009-08-20 Bharat Kumar Yerra , Bacham Eswar Reddy

In this work, we studied the distribution of lithium abundances in giants as a function of stellar mass. We used a sample of 1240 giants common among Kepler photometric and LAMOST medium resolution (R $\approx$ 7500) spectroscopic survey…

Solar and Stellar Astrophysics · Physics 2023-02-13 Anohita Mallick , Raghubar Singh , Bacham E. Reddy

Using the sample of 348 stars from the PennState-Torun Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we…

Solar and Stellar Astrophysics · Physics 2015-06-22 M. Adamow , A. Niedzielski , E. Villaver , A. Wolszczan , G. Nowak

A model scenario has recently been introduced to explain the presence of very strong Li lines in the spectra of some low mass K giant stars (de la Reza et al. 1996). In this scenario all ordinary, Li poor, K giants become Li rich during a…

Astrophysics · Physics 2009-10-30 R. de la Reza , N. A. Drake , L. da Silva , C. A. O. Torres , E. L. Martin

We report on spectroscopic analyses of three K giants previously suggested to be Li-rich: IRAS 12327-6523, IRAS 13539-4153, and IRAS 17596-3952. High-resolution optical spectra and the LTE model atmospheres are used to derive the stellar…

Astrophysics · Physics 2009-11-10 Bacham E. Reddy , David L. Lambert

In this article, we speculate on the possible mechanisms for Li enhancement origin in RGB stars based on a large data set of around 340,299 stars collected from the GALAH survey combined with the Gaia astrometry. Data has 51,982 low mass…

Solar and Stellar Astrophysics · Physics 2019-01-29 Deepak , Bacham Eswar Reddy

Lithium rich stars in globular clusters are rare. In fact, only 14 have been found so far, in different evolutionary phases from dwarfs to giants. Different mechanisms have been proposed to explain this enhancement, but it is still an open…

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