English
Related papers

Related papers: A possible signature of non-uniform Be-\alpha rela…

200 papers

We discuss the early evolution of beryllium and oxygen in our Galaxy by comparing abundances of these elements for halo and disk metal-poor stars. Both, O and Be rise as we go progressively to more metal-rich stars, showing a slope 0.41…

Astrophysics · Physics 2007-05-23 Garik Israelian , Ramon Garcia Lopez , Rafael Rebolo

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 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 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

[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

We investigate the evolution of the star formation rate in the early Galaxy using beryllium and oxygen abundances in metal poor stars. Specifically, we show that stars belonging to two previously identified kinematical classes (the…

Astrophysics · Physics 2016-08-30 L. Pasquini , D. Galli , R. G. Gratton , P. Bonifacio , S. Randich , G. Valle

We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated…

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

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

Beryllium stellar abundances were suggested to be a good tracer of time in the early Galaxy. In an investigation of its use as a cosmochronometer, using a large sample of local halo and thick-disk dwarfs, evidence was found that in a…

Astrophysics of Galaxies · Physics 2015-05-14 Rodolfo Smiljanic , L. Pasquini , P. Bonifacio , D. Galli , B. Barbuy , R. Gratton , S. Randich

In this paper we present beryllium (Be) abundances in a large sample of 41 extra-solar planet host stars, and for 29 stars without any known planetary-mass companion, spanning a large range of effective temperatures. The Be abundances were…

Be/X-ray binaries comprise roughly two-thirds of the high-mass X-ray binaries (HMXBs), which is a class of X-ray binaries that results from the high mass of the companion or donor star (> 10 solar masses). Currently the formation and…

Astrophysics · Physics 2007-05-23 P. D. Kiel , J. R. Hurley , J. R. Murray , K. Hayasaki

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

The single stable isotope of beryllium is a pure product of cosmic-ray spallation in the ISM. Assuming that the cosmic-rays are globally transported across the Galaxy, the beryllium production should be a widespread process and its…

Solar and Stellar Astrophysics · Physics 2015-05-14 R. Smiljanic , L. Pasquini , P. Bonifacio , D. Galli , B. Barbuy , R. Gratton , S. Randich

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

We present observations of the Be II 313.0 nm resonance doublet in 14 halo and old disk stars with metallicities ranging from [Fe/H]=-0.4 to about -3.0 obtained with the CASPEC spectrograph of the ESO 3.6m telescope at a FWHM about 8.6 km/s…

Astrophysics · Physics 2007-05-23 P. Molaro , P. Bonifacio , F. Castelli , L. Pasquini

A previous study (Nissen & Schuster 2010) of 94 dwarf stars with -1.6 < [Fe/H] < -0.4 has revealed the existence of two distinct halo populations with a systematic difference in [alpha/Fe] at a given metallicity. In continuation of that…

Astrophysics of Galaxies · Physics 2015-05-27 Poul E. Nissen , William J. Schuster

We present a photometric survey aimed to characterize the Be star population of young open clusters. It is found that in these clusters early-type Be stars are more frequent than in the galactic field, and late-type Be stars are scarce or…

Astrophysics · Physics 2007-05-23 Juan Fabregat

Because of the roughly linear correlation between Be/H and Fe/H in low metallicity halo stars, it has been argued that a ``primary'' component in the nucleosynthesis of Be must be present in addition to the ``secondary'' component from…

Astrophysics · Physics 2009-10-30 Brian D. Fields , Keith A. Olive
‹ Prev 1 2 3 10 Next ›