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Related papers: Lithium in the Intermediate-Age Open Cluster, NGC …

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Old open clusters are very useful targets to investigate mechanisms responsible for lithium (Li) depletion during the main sequence. Comparison of the Li abundances in clusters of different age allows us to understand the efficiency of the…

Astrophysics · Physics 2009-11-13 Loredana Prisinzano , Sofia Randich

We present Li abundances for 14 solar-type stars in the intermediate age (~ 2 Gyr) clusters IC 4651 and NGC 3680. The log n(Li) vs. effective temperature distributions are compared with those of the similar age cluster NGC 752, of the…

Astrophysics · Physics 2007-05-23 S. Randich , L. Pasquini , R. Pallavicini

We have analyzed high-dispersion spectra in the Li 6708 Angstrom region for 167 stars within the anticenter cluster, NGC 2204. From 105 probable members, abundance analysis of 45 evolved stars produces [Fe/H] = -0.40 +/- 0.12, [Si/Fe] =…

Solar and Stellar Astrophysics · Physics 2024-06-28 Barbara J. Anthony-Twarog , Constantine P. Deliyannis , Aaron Steinhauer , Qinghui Sun , Bruce A. Twarog

High-dispersion spectra in the Li 6708 Angstrom region have been obtained and analyzed in the old, metal-deficient cluster, NGC 2243. From Hydra spectra for 29 astrometric and radial-velocity members, we derive rotational velocities, as…

Astrophysics of Galaxies · Physics 2021-03-10 B. J. Anthony-Twarog , C. P. Deliyannis , . B. A. Twarog

Hydra spectra of 85 G-K dwarfs in the young cluster, M35, near the Li 6708 Angstrom line region are analyzed. From velocities and Gaia astrometry, 78 are likely single-star members which, combined with previous work, produces 108 members…

Solar and Stellar Astrophysics · Physics 2018-07-18 B. J. Anthony-Twarog , C. P. Deliyannis , D. Harmer , D. B. Lee-Brown , A. Steinhauer , Q. Sun , B. A. Twarog

We present spectroscopic observations of candidate F, G and K type stars in NGC 6633, an open cluster with a similar age to the Hyades. We identify 10 new cluster members including one short period binary system. Combining this survey with…

Astrophysics · Physics 2009-11-07 R. D. Jeffries , E. J. Totten , S. Harmer , C. P. Deliyannis

We present lithium abundances for 119 main-sequence stars in the old open cluster NGC 188 (age = 6.3 Gyr), using high-resolution, high signal-to-noise ratio spectra from WIYN/Hydra. We observe the stars over multiple nights and measure…

Solar and Stellar Astrophysics · Physics 2025-09-19 Qinghui Sun , Constantine P. Deliyannis , Bruce A. Twarog , Barbara J. Anthony-Twarog

We have obtained new photometry and intermediate resolution ($\Delta \lambda = 2.7$ \AA\ ) spectra of 19 of these objects (14.9 $\le$ $I_c$ $\le$ 17.5) in order to confirm cluster membership. We identify 15 of our targets as likely cluster…

Astrophysics · Physics 2011-02-11 D. Barrado y Navascues , J. R. Stauffer , B. M. Patten

We consider WIYN/Hydra spectra of 329 photometric candidate members of the 420-Myr-old open cluster M48, and report Lithium detections or upper limits for 234 members and likely members. The 171 single members define a number of notable…

Solar and Stellar Astrophysics · Physics 2023-07-26 Qinghui Sun , Constantine P. Deliyannis , Aaron Steinhauer , Barbara J. Anthony-Twarog , Bruce A. Twarog

High-resolution CTIO 4-m/HYDRA spectroscopy of the super-metal-rich open cluster NGC 6253 ([Fe/H]=+0.43+/-0.01) has been used to study the stellar lithium (Li) abundances near the cluster's turnoff. NGC 6253 greatly expands the range of…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Cummings , Constantine P. Deliyannis , Barbara Anthony-Twarog , Bruce Twarog , Ryan M. Maderak

We present a survey of lithium abundances in 185 main- sequence field stars with Teff between 5600 and 6600 K and [Fe/H] from -1.4 to +0.2 based on high-resolution spectra of 130 stars and a reanalysis of data from Lambert et al. (1991).…

Astrophysics · Physics 2009-11-06 Y. Q. Chen , P. E. Nissen , T. Benoni , G. Zhao

Lithium-rich giant stars are rare and their existence challenges our understanding of stellar structure and evolution. We profit from the high-quality sample gathered with HARPS and UVES, in order to search for Li-rich giants and to…

Solar and Stellar Astrophysics · Physics 2023-06-21 M. Tsantaki , E. Delgado-Mena , D. Bossini , S. G. Sousa , E. Pancino , J. H. C. Martins

Measurements of lithium (Li) abundances in open clusters provide a unique tool for following the evolution of this element with age, metallicity, and stellar mass. Using FLAMES/Giraffe on the VLT, we obtained spectra of 157 candidate…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Randich , G. Pace , L. Pastori , A. Bragaglia

Lithium is a fundamental element for studying the mixing mechanisms acting in the stellar interiors, for understanding the chemical evolution of the Galaxy and the Big Bang nucleosynthesis. The study of Li in stars of open clusters…

Solar and Stellar Astrophysics · Physics 2015-06-15 P. Francois , L. Pasquini , K. Biazzo , P. Bonifacio , R. Palsa

Lithium (Li) abundance is an age indicator for G, K, and M stellar types, as its abundance decreases over time for these spectral types. However, despite the observational efforts made over the past few decades, the role of rotation,…

Solar and Stellar Astrophysics · Physics 2024-05-15 D. Cuenda-Muñoz , D. Barrado , M. A. Agüeros , J. L. Curtis , H. Bouy

We have determined Li abundances for 11 G-type stars in the 6-8 Gyr old open cluster NGC 188. These data significantly enlarge the number of cluster stars with Li measurements, allowing us to extend the investigation of Li depletion in open…

Astrophysics · Physics 2008-11-26 Sofia Randich , Paola Sestito , Roberto Pallavicini

CCD photometry on the uvbyCaHbeta system is presented for the open cluster, NGC 3680. Restricting the data to probable cluster members using the CMD and the photometric indices alone defines a sample of 34 stars at the cluster turnoff that…

Astrophysics · Physics 2009-11-10 B. J. Anthony-Twarog , B. A. Twarog

Our aim was to determine the initial Li content of two clusters of similar metallicity but very different ages, the old open cluster NGC 2243 and the metal-rich globular cluster NGC 104. We compared the lithium abundances derived for a…

Solar and Stellar Astrophysics · Physics 2021-09-08 Misa Aoki , Francesca Primas , Luca Pasquini , Achim Weiss , Maurizio Salaris , Daniela Carollo

We have carried out a high resolution spectroscopic survey of the 220-250 Myr old cluster NGC 6475: our main purpose is to investigate Li evolution during the early stages of the Main Sequence. We have determined Li abundances for 33 late F…

Astrophysics · Physics 2009-11-07 Paola Sestito , Sofia Randich , Jean-Claude Mermilliod , Roberto Pallavicini

WIYN/Hydra spectroscopy (at R~15,000) of the moderately metal-rich Praesepe and Hyades open clusters was used to study their main sequence (MS) iron ([Fe/H]) and lithium (A(Li)) abundances. Self-consistent [Fe/H] and Li analyses of these…

Solar and Stellar Astrophysics · Physics 2017-03-08 Jeffrey D. Cummings , Constantine P. Deliyannis , Ryan M. Maderak , Aaron Steinhauer
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