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Related papers: Lithium in LMC carbon stars

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We identify the rich Carbon star population of the Magellanic-type dwarf irregular galaxy WLM (Wolf-Lundmark-Melotte) and study its photometric properties from deep near-IR observations. The galaxy exhibits also a clear presence of Oxygen…

Astrophysics · Physics 2009-11-13 A. T. Valcheva , V. D. Ivanov , E. P. Ovcharov , P. L. Nedialkov

We derive the first detailed chemical abundances of three star clusters in the Large Magellanic Cloud (LMC), NGC1831 (436+/-22 Myr), NGC1856 (350+/-18 Myr) and [SL63]268 (1230+/-62 Myr) using integrated-light spectroscopic observations…

Astrophysics of Galaxies · Physics 2022-05-11 Randa Asa'd , S. Hernandez , A. M. As'ad , M. Molero , F. Matteucci , S. Larsen , Igor V. Chilingarian

The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 J. Christopher Howk , Nicolas Lehner , Brian D. Fields , Grant J. Mathews

The luminosities and periods of obscured AGB stars in the LMC are discussed using a combination of ISO and ground-based infrared photometry. The bolometric luminosities of these stars fall close to an extrapolation of the period-luminosity…

Astrophysics · Physics 2007-05-23 Patricia Whitelock , Michael Feast

Weak G-band (WGB) stars are a rare class of cool luminous stars that present a strong depletion in carbon, but also lithium abundance anomalies that have been little explored in the literature since the first discovery of these peculiar…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. Palacios , M. Parthasarathy , Y. Bharat Kumar , G. Jasniewicz

We report the APOGEE-2S$+$ discovery of a unique collection of nitrogen-enhanced mildly metal-poor giant stars, peaking at [Fe/H]$\sim -0.89$ with no carbon enrichment, toward the Small and Large Magellanic Clouds (MCs), with abundances of…

The vast majority of stars with mass similar to the Sun are expected to only destroy lithium over the course of their lives, via low-temperature nuclear burning. This has now been supported by observations of hundreds of thousands of red…

Solar and Stellar Astrophysics · Physics 2020-07-15 Yerra Bharat Kumar , Bacham E. Reddy , Simon W. Campbell , Sunayana Maben , Gang Zhao , Yuan-Sen Ting

We report the discovery of a possible symbiotic star, in the Large Magellanic Cloud (LMC). The object under consideration here, designated as RP 870, was detected during the course of a comprehensive H$\alpha$ survey of the LMC by Reid &…

Solar and Stellar Astrophysics · Physics 2017-11-28 Blesson Mathew , Warren A. Reid , R. E. Mennickent , D. P. K. Banerjee

We investigate if there is a difference in the lithium abundances of stars belonging to two halo populations of F and G main-sequence stars previously found to differ in [alpha/Fe] for the metallicity range -1.4 < [Fe/H] < -0.7. Li…

Astrophysics of Galaxies · Physics 2015-06-05 P. E. Nissen , W. J. Schuster

We present the discovery of 2MASS J05241392-0336543 (hereafter J0524-0336), a very metal-poor ([Fe/H]=-2.43 +- 0.16), highly r-process-enhanced ([Eu/Fe]= +1.34 +- 0.10) Milky Way halo field red giant star, with an ultra high Li abundance of…

Planetary engulfment events have long been proposed as a lithium (Li) enrichment mechanism contributing to the population of Li-rich giants (A(Li) >= 1.5 dex). Using MESA stellar models and A(Li) abundance measurements obtained by the GALAH…

Solar and Stellar Astrophysics · Physics 2021-12-08 M. Soares-Furtado , Matteo Cantiello , Morgan MacLeod , Melissa K. Ness

In this work, we study the chemical compositions and kinematic properties of six metal-poor stars with [Fe/H] $< -2.5$ in the Galactic halo. From high-resolution (R $\sim$~110,000) spectroscopic observations obtained with the Lick/APF, we…

Astrophysics of Galaxies · Physics 2019-09-04 Mohammad K. Mardini , Vinicius M. Placco , Ali Taani , Haining Li , Gang Zhao

We make use of high resolution, high signal-to-noise ratio spectra of 12 turn-off stars in the metal-poor globular cluster NGC 6397 to measure its lithium content. We conclude that they all have the same lithium abundance A(Li) = 2.34 with…

The first detection of ammonia (NH3) is reported from the Magellanic Clouds. Using the Australia Telescope Compact Array, we present a targeted search for the (J,K) = (1,1) and (2,2) inversion lines towards seven prominent star-forming…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Juergen Ott , Christian Henkel , Lister Staveley-Smith , Axel Weiss

The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. J. Liu , K. F. Tan , L. Wang , G. Zhao , Bun'ei Sato , Y. Takeda , H. N. Li

Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate {\it Hipparcos} parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin disk. This…

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

The Large Magellanic Cloud (LMC) has an extensive H$_{\alpha}$ emission halo that traces an extended, warm ionized component of its interstellar medium. Using the Wisconsin H$_{\alpha}$ Mapper (WHAM) telescope, we present the first…

Astrophysics of Galaxies · Physics 2023-05-18 B. M. Smart , L. M. Haffner , K. A. Barger , D. A. Ciampa , A. S. Hill , D. Krishnarao , G. J. Madsen

Most of relatively warm, unevolved metal-poor stars ($T_{\rm eff}\gtrsim 5800\,\mathrm{K}$ and $[{\rm Fe/H}]\lesssim -1.5$) exhibit almost constant lithium abundances, irrespective of metallicity or effective temperature, and thus form the…

Solar and Stellar Astrophysics · Physics 2017-06-21 Tadafumi Matsuno , Wako Aoki , Takuma Suda , Haining Li

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

We have determined Li abundances for eleven metal-poor turn-off stars, among which eight have [Fe/H]<-3, based on LTE analyses of high-resolution spectra obtained with the HDS on the Subaru telescope. The Li abundances for four of these…

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