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Related papers: Galactic Evolution of Beryllium and Oxygen

200 papers

We review the main sources of LiBeB production and show that a primary mechanism is at work in the early Galaxy involving both ejection and acceleration of He, C and O at moderate energy, which by nuclear interaction with H and He produce…

Astrophysics · Physics 2016-11-03 M. Casse , E. Vangioni-Flam , J. Audouze

We have derived abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba for 43 metal-poor field stars in the solar neighbourhood with iron abundances [Fe/H] ranging from -0.4 to -3.0. Total abundance errors are estimated to about…

We present a general set of calculations decribing the chemical evolution of young massive galaxies and predict the evolution of the CO, O2, and dust abundances as a function of age and metallicity.

Astrophysics · Physics 2009-10-30 D. T. Frayer , R. L. Brown

Thanks to their usefulness in various fields of astrophysics (e.g. mixing processes in stars, chemical evolution of galaxies), the last few years have witnessed a large increase in the amount of abundance data for early-type stars. Two…

Astrophysics · Physics 2008-11-26 T. Morel

Metal-poor stars provide the fossil record of Galactic chemical evolution and the nucleosynthesis processes that took place at the earliest times in the history of our Galaxy. From detailed abundance studies of low mass, extremely…

Solar and Stellar Astrophysics · Physics 2015-03-11 T. Hansen , C. J. Hansen , N. Christlieb , D. Yong , T. C. Beers , J. Andersen

Several studies have shown recently that at low metallicity B-type stars rotate faster than in environments of high metallicity. This is a typical case in the SMC. As a consequence, it is expected that a larger number of fast rotators is…

Solar and Stellar Astrophysics · Physics 2010-10-19 Christophe Martayan , Jean Zorec , Dietrich Baade , Yves Fremat , Juan Fabregat , Sylvia Ekstrom

Barium is a key element in constraining the evolution of the (not well understood) r-process in the first galactic stars and currently the Ba abundances in these very metal-poor stars were mostly measured under the Local Thermodynamical…

Astrophysics of Galaxies · Physics 2009-11-13 S. M. Andrievsky , M. Spite , S. A. Korotin , F. Spite , P. Francois , P. Bonifacio , R. Cayrel , V. Hill

The actual value of the oxygen abundance of the metal-poor planetary nebula PN G135.9+55.9 has frequently been debated in the literature. We wanted to clarify the situation by making an improved abundance determination based on a study that…

Solar and Stellar Astrophysics · Physics 2014-11-20 C. Sandin , R. Jacob , D. Schönberner , M. Steffen , M. M. Roth

The damped Lyman alpha systems seen in the spectra of high redshift QSOs offer the means to determine element abundances in galaxies observed while still at an early stage of evolution. Such measurements, which have only recently come…

Astrophysics · Physics 2016-08-30 Max Pettini , Keith Lipman , Richard W. Hunstead

In the present universe, the gas is a minor component of giant galaxies, and its dominant phase is atomic (HI). During galaxy evolution in cosmic times, models predict that gas fractions were much higher in galaxies, and gas phases could be…

Astrophysics of Galaxies · Physics 2018-03-14 Francoise Combes

We calculate the evolution of heavy element abundances from C to Zn in the solar neighborhood adopting our new nucleosynthesis yields. Our yields are calculated for wide ranges of metallicity (Z=0-Z_\odot) and the explosion energy (normal…

Astrophysics · Physics 2008-11-26 C. Kobayashi , H. Umeda , K. Nomoto , N. Tominaga , T. Ohkubo

Understanding the evolution of carbon and iron in the Milky Way's halo is of importance because these two elements play crucial roles constraining star formation, Galactic assembly, and chemical evolution in the early Universe. Here, we…

From exploratory studies and theoretical expectations it is known that simplifying approximations in spectroscopic analysis (LTE, 1D) lead to systematic biases of stellar parameters and abundances. These biases depend strongly on surface…

Solar and Stellar Astrophysics · Physics 2017-10-04 Maria Bergemann , Remo Collet , Ralph Schoenrich , Rene Andrae , Mikhail Kovalev , Gregory Ruchti , Camilla J. Hansen , Zazralt Magic

Of all the light elements, lithium is the most sensitive indicator of stellar evolution. This review discusses current data on the abundance of lithium in the atmospheres of A-, F-, G-, and K-stars of different types, as well as the…

Solar and Stellar Astrophysics · Physics 2017-01-23 L. S. Lyubimkov

Our current knowledge of star-forming metallicity relies primarily on gas-phase oxygen abundance measurements. This may not allow one to accurately describe differences in stellar evolution and feedback driven by variations in iron…

Astrophysics of Galaxies · Physics 2024-06-19 Martyna Chruślińska , Ruediger Pakmor , Jorryt Matthee , Tadafumi Matsuno

We compute the chemical evolution of the Galactic bulge in the context of an inside-out model for the formation of the Milky Way. The model contains updated stellar yields from massive stars. The main purpose of the paper is to compare the…

Astrophysics · Physics 2009-11-13 Silvia K. Ballero , Francesca Matteucci , Livia Origlia , R. Michael Rich

We argue that extreme metal-poor stars show a high dispersion in metallicity, because their abundances are the outcome of very few supernova events. Abundance anomalies should appear because of the discrete range of progenitor masses. There…

Astrophysics · Physics 2009-10-28 Jean Audouze , Joseph Silk

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

Recent dynamical analysis based on Gaia data have revealed major accretion events in Milky Way's history. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and…

CONTEXT: [ABRIDGED]. For the Milky Way bulge, there are currently essentially no measurements of carbon in un-evolved stars, hampering our abilities to properly compare Galactic chemical evolution models to observational data for this still…

Astrophysics of Galaxies · Physics 2021-12-01 T. Bensby , A. Gould , M. Asplund , S. Feltzing , J. Meléndez , J. A. Johnson , S. Lucatello , A. Udalski , J. C. Yee
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