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Related papers: Detecting weak beryllium lines with CUBES

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The element beryllium is detected for the first time in white dwarf stars. This discovery in the spectra of two helium-atmosphere white dwarfs was made possible only because of the remarkable overabundance of Be relative to all other…

Solar and Stellar Astrophysics · Physics 2021-06-23 Beth Klein , Alexandra E. Doyle , B. Zuckerman , P. Dufour , Simon Blouin , Carl Melis , Alycia J. Weinberger , Edward D. Young

We present detailed chemical abundances for the bright carbon-enhanced metal-poor (CEMP) star BD+44 493, previously reported on by Ito et al. Our measurements confirm that BD+44 493 is an extremely metal-poor ([Fe/H]=-3.8) subgiant star…

Solar and Stellar Astrophysics · Physics 2015-06-16 H. Ito , W. Aoki , T. C. Beers , N. Tominaga , S. Honda

Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the…

The Be isotopic measurements preliminarily reported by the AMS-02 Collaboration have reached an unprecedented energy of 12 GeV/$n$. As secondary cosmic rays (CRs), the Be isotopes include both stable and unstable species, which are crucial…

High Energy Astrophysical Phenomena · Physics 2024-02-08 Meng-Jie Zhao , Xiao-Jun Bi , Kun Fang , Peng-Fei Yin

We present new UVES spectra of a sample of 15 cool unevolved stars with and without detected planetary companions. Together with previous determinations, we study Be depletion and possible differences in Be abundances between both groups of…

Solar and Stellar Astrophysics · Physics 2015-06-03 E. Delgado Mena , G. Israelian , J. I. González Hernández , N. C. Santos , R. Rebolo

The non-local thermodynamic equilibrium (NLTE) line formation of neutral boron in the atmospheres of cool stars are investigated. Our results confirm that NLTE effects for the B I resonance lines, which are due to a combination of…

Solar and Stellar Astrophysics · Physics 2010-04-07 Kefeng Tan , Jianrong Shi , Gang Zhao

The science case on studies of accretion and outflows in low-mass ($<$1.5 $M_{\odot}$) young stellar objects (YSOs) with the new CUBES instrument is presented. We show the need for a high-sensitivity, near-ultraviolet (NUV) spectrograph…

Solar and Stellar Astrophysics · Physics 2022-03-30 J. M. Alcalá , G. Cupani , C. J. Evans , M. Franchini , B. Nisini

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…

Elements with weak and blended spectral features in stellar spectra are challenging to measure and require specialized analysis methods to precisely measure their chemical abundances. In this work, we have created a catalog of approximately…

Abundances of about 18 elements including the heavy elements Y and Zr are determined from Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectra of seven extreme helium stars (EHes): LSE 78, BD+10 2179, V1920 Cyg,…

Astrophysics · Physics 2016-08-30 Gajendra Pandey , David L. Lambert , C. Simon Jeffery , N. Kameswara Rao

The chemical evolution of neutron capture elements in the Milky Way is still a matter of debate. Although more and more studies investigate their chemical behaviour, there is still a lack of a significant large sample of abundances of a key…

Solar and Stellar Astrophysics · Physics 2024-08-30 G. Contursi , P. de Laverny , A. Recio-Blanco , M. Molero , E. Spitoni , F. Matteucci , S. Cristallo

The present-day abundance of beryllium in the solar atmosphere provides clues about mixing mechanisms within stellar interiors. However, abundance determinations based on the Be II 313.107 nm line are prone to systematic errors due to…

Solar and Stellar Astrophysics · Physics 2024-09-09 A. M. Amarsi , D. Ogneva , G. Buldgen , N. Grevesse , Y. Zhou , P. S. Barklem

The surface content of lithium (Li) and beryllium (Be) provide insights into the mixing and circulation mechanisms in stellar interiors. The old open cluster, M 67, has been well-studied for Li abundances in both main-sequence and evolved…

Solar and Stellar Astrophysics · Physics 2019-10-18 Ann Merchant Boesgaard , Michael G. Lum , Constantine P. Deliyannis

Theoretical prediction of surface stellar abundances of light elements -- lithium, beryllium, and boron -- represents one of the most interesting open problems in astrophysics. As well known, several measurements of 7-Li abundances in…

Solar and Stellar Astrophysics · Physics 2021-07-07 E. Tognelli , S. Degl'Innocenti , P. G. Prada Moroni , L. Lamia , R. G. Pizzone , A. Tumino , C. Spitaleri , A. Chiavassa

We present an analytic calculation of the thermonuclear depletion of the light elements lithium, beryllium, and boron in fully convective, low-mass stars. Under the presumption that the pre--main-sequence star is always fully mixed during…

Carbon-enhanced metal-poor (CEMP) stars are believed to show the chemical imprints of more massive stars (M > 0.8 Msun) that are now extinct. In particular, it is expected that the observed abundance of Li should deviate in these stars from…

Solar and Stellar Astrophysics · Physics 2012-06-01 T. Masseron , J. A. Johnson , S. Lucatello , A. Karakas , B. Plez , T. C. Beers , N. Christlieb

Context. Efforts to look for signatures of the first stars have concentrated on metal-poor halo objects. However, the low end of the bulge metallicity distribution has been shown to host some of the oldest objects in the Milky Way and hence…

Solar and Stellar Astrophysics · Physics 2016-09-28 C. Siqueira-Mello , C. Chiappini , B. Barbuy , K. Freeman , M. Ness , E. Depagne , E. Cantelli , M. Pignatari , R. Hirschi , U. Frischknecht , G. Meynet , A. Maeder

We have observed the B I 2497 A line to derive the boron abundances of two very metal-poor stars selected to help in tracing the origin and evolution of this element in the early Galaxy: BD +23 3130 and HD 84937. The observations were…

Astrophysics · Physics 2009-10-30 R. J. Garcia Lopez , D. L. Lambert , B. Edvardsson , B. Gustafsson , D. Kiselman , R. Rebolo

The early Universe presented a star formation environment that was almost devoid of heavy elements. The lowest metallicity stars thus provide a unique window into the earliest Galactic stages, but are exceedingly rare and difficult to find.…