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Related papers: New beryllium observations in low-metallicity star…

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The abundance of beryllium in the oldest, most metal-poor stars acts as a probe of early star formation and Galactic chemical evolution. We have analyzed high-resolution, high signal-to-noise Keck/HIRES spectra of 24 stars with [Fe/H] from…

Astrophysics of Galaxies · Physics 2011-02-11 Jeffrey A. Rich , Ann Merchant Boesgaard

The study of Be in stars of differing metal content can elucidate the formation mechanisms and the Galactic chemical evolution of Be. We have obtained high-resolution, high signal-to-noise spectra of the resonance lines of Be II in eight…

Astrophysics · Physics 2009-11-13 Ann Merchant Boesgaard , Megan C. Novicki

We report on a new spectroscopic analysis of the very metal deficient star G 64-12 ([Fe/H]=-3.3), aimed at determining, for the first time, its Be content. The spectra were observed during the Science Verification of UVES, the ESO VLT…

Astrophysics · Physics 2007-05-23 F. Primas , M. Asplund , P. E. Nissen , V. Hill

There are nine metal-deficient stars that have Li abundances well below the Li plateau that is defined by over 100 unevolved stars with temperatures above 5800 K and values of [Fe/H] $<$ $-$1.0. Abundances of Be have been determined for…

Astrophysics · Physics 2009-11-13 Ann Merchant Boesgaard

The light elements, Li, Be, and B, provide tracers for many aspects of astronomy including stellar structure, Galactic evolution, and cosmology. We have taken spectra of Be in 117 metal-poor stars ranging in metallicity from [Fe/H] = -0.5…

Solar and Stellar Astrophysics · Physics 2015-05-30 Ann Merchant Boesgaard , Jeffrey A. Rich , Emily M. Levesque , Brendan P. Bowler

Abundances of beryllium in metal-poor stars scale linearly with metallicity down to [Fe/H] ~ -3.0. In the stars where Be has been detected at this extremely metal-poor regime, an increased abundance scatter has been previously reported.…

Solar and Stellar Astrophysics · Physics 2021-02-10 Rodolfo Smiljanic , Mateusz G. Zych , Luca Pasquini

We have determined Be abundances in 50 F and G dwarfs in the mass range of 0.9 $\leq$ M$_\odot$ $\leq$ 1.1 as determined by Lambert & Reddy. The effective temperatures are 5600 to 6400 K and metallicities from $-$0.65 to +0.11. The spectra…

Astrophysics · Physics 2015-05-13 Ann Merchant Boesgaard , Julie A. Krugler

We have determined beryllium abundances for 25 metal-poor stars based on the high resolution and high signal-to-noise ratio spectra from the VLT/UVES database. Our results confirm that Be abundances increase with Fe, supporting the global…

Astrophysics · Physics 2009-11-13 K. F. Tan , J. R. Shi , G. Zhao

An extensive beryllium abundance analysis was conducted for 118 solar analogs (along with 87 FGK standard stars) by applying the spectrum synthesis technique to the near-UV region comprising the Be II line at 3131.066 A, in an attempt to…

Solar and Stellar Astrophysics · Physics 2015-05-27 Yoichi Takeda , Akito Tajitsu , Satoshi Honda , Satoshi Kawanomoto , Hiroyasu Ando , Takashi Sakurai

Beryllium is not destroyed as easily as Li, so the abundances of Li and Be together can tell us more about the internal physical processes in stars than either element can alone. We have obtained high-resolution (45,000) and high…

Astrophysics · Physics 2009-11-07 Ann Merchant Boesgaard , Jeremy R. King

We have determined Li abundances in 55 metal-poor (3.6 < [Fe/H] < -0.7) stars with extreme orbital kinematics. We find the Li abundance in the Li-plateau stars and examine its decrease in low-temperature, low-mass stars. The Li observations…

Astrophysics · Physics 2009-11-13 Ann Merchant Boesgaard , Alex Stephens , Constantine P. Deliyannis

The simultaneous investigation of Li and Be in stars is a powerful tool in the study of the evolutionary mixing processes. Here, we present beryllium abundances in stars along the whole evolutionary sequence of the open cluster IC 4651.…

Solar and Stellar Astrophysics · Physics 2015-05-14 Rodolfo Smiljanic , L. Pasquini , C. Charbonnel , N. Lagarde

[abridged] Beryllium is a pure product of cosmic ray spallation. This implies a relatively simple evolution in time of the beryllium abundance and suggests its use as a time-like observable. We study the evolution of Be in the early Galaxy…

Astrophysics of Galaxies · Physics 2015-05-13 R. Smiljanic , L. Pasquini , P. Bonifacio , D. Galli , R. G. Gratton , S. Randich , B. Wolff

A sample of metal-poor subgiants has been observed with the UVES spectrograph at the Very Large Telescope and abundances of Li and Be have been determined. Typical signal-to-noise per spectral bin values for the co-added spectra are of the…

Astrophysics · Physics 2016-08-16 A. E. García Pérez , F. Primas

An extensive spectroscopic study was carried out for the beryllium abundances of 200 red giants (mostly of late G and early K type), which were determined from the near-UV Be II 3131.066 line based on high-dispersion spectra obtained by…

Solar and Stellar Astrophysics · Physics 2015-06-22 Yoichi Takeda , Akito Tajitsu

Context. The chemistry and Galactic velocity components of the star HD 65907 suggest that despite its young isochronal age of $\sim$5 Gyr, it is in fact a merger of two old Population II stars. Its low Li abundance is also consistent with a…

Solar and Stellar Astrophysics · Physics 2024-11-26 Anne Rathsam , Jorge Meléndez , Amanda I. Karakas

The surface content of lithium (Li) and beryllium (Be) in stars can reveal important information about the temperature structure and physical processes in their interior regions. This study focuses on solar-type stars with a sample that is…

Solar and Stellar Astrophysics · Physics 2022-12-14 Ann Merchant Boesgaard , Constantine P. Deliyannis , Michael G. Lum , Ashley Chontos

Lithium and beryllium are destroyed at different temperatures in stellar interiors. As such, their relative abundances offer excellent probes of the nature and extent of mixing processes within and below the convection zone. We determine Be…

Solar and Stellar Astrophysics · Physics 2015-06-24 M. Tucci Maia , J. Meléndez , M. Castro , M. Asplund , I. Ramírez , T. R. Monroe , J. D. do Nascimento , D. Yong

We present the results of observations of the $\lambda 3130.4$ \AA interstellar absorption line of Be II in the direction of zeta Per. The data were obtained at the Canada-France-Hawaii 3.6m Telescope using the Coud\'e f/4 Gecko…

Astrophysics · Physics 2016-08-30 Guillaume Hébrard , Martin Lemoine , Roger Ferlet , Alfred Vidal-Madjar

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster
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