Nucleosynthesis, Mixing Processes, and Gas Pollution from AGB Stars
Universe, 2022 We discuss the evolution of stars through the asymptotic giant branch, focusing on the physical mechanisms potentially able to alter the surface chemical composition and on how changes in the chemistry of the external regions affect the physical ...
Paolo Ventura +6 more
doaj +1 more source
The Interaction Between Accretion from the Interstellar Medium and Accretion from the Evolved Binary Component in Barium Stars [PDF]
Journal of Astronomy and Space Sciences, 2018 The reanalysis of the previously published abundance pattern of mild barium star HD202109 (ζ Cyg) and the chemical compositions of 129 thin disk barium stars facilitated the search for possible correlations of different stellar parameters with second ...
Yeuncheol Jeong +2 more
doaj +1 more source
Structure formation cosmic rays: Identifying observational constraints [PDF]
Serbian Astronomical Journal, 2005 Shocks that arise from baryonic in-fall and merger events during the structure formation are believed to be a source of cosmic rays. These "structure formation cosmic rays" (SFCRs) would essentially be primordial in composition, namely, mostly made of ...
Prodanović T., Fields B.D.
doaj +1 more source
Magellanic Clouds Cepheids: Thorium Abundances [PDF]
Journal of Astronomy and Space Sciences, 2018 The analysis of the high-resolution spectra of 31 Magellanic Clouds Cepheid variables enabled the identification of thorium lines. The abundances of thorium were found with spectrum synthesis method. The calculated thorium abundances exhibit correlations
Yeuncheol Jeong +5 more
doaj +1 more source
The Record-Warm Barents Sea and 0-Group Fish Response to Abnormal Conditions
Frontiers in Marine Science, 2020 The Barents Sea is a nursery area for many commercially and ecologically important fish stocks, and this whole region is presently subject to rapid climatic change from a cold period in the 1980s to a record warm period in the latest decade, with a peak ...
Elena Eriksen +7 more
doaj +1 more source
Indirect Measurements of n- and p-Induced Reactions of Astrophysical Interest on Oxygen Isotopes
Frontiers in Astronomy and Space Sciences, 2020 Observations of abundances and isotopic ratio determinations in stars yield powerful constraints on stellar models. In particular, the oxygen isotopic ratios are of particular interest because they are affected not only by nucleosynthesis but also by ...
M. L. Sergi +12 more
doaj +1 more source
Connecting the primordial and Galactic deuterium abundances [PDF]
, 2007 The deuterium abundances inferred from observations of the interstellar medium within 1-2 kpc of the Sun range over a factor of three and the corresponding oxygen abundances show an even larger dispersion.
Romano, Donatella +2 more
core +3 more sources
Neon and Sulfur Abundances of Planetary Nebulae in the Magellanic Clouds [PDF]
, 2007 The chemical abundances of neon and sulfur for 25 planetary nebulae (PNe) in the Magellanic Clouds are presented. These abundances have been derived using mainly infrared data from the Spitzer Space Telescope.
Aller L. H. +12 more
core +4 more sources
Chemical Composition of RM_1-390 - Large Magellanic Cloud Red Supergiant [PDF]
Journal of Astronomy and Space Sciences, 2017 A high resolution spectroscopic observation of the red supergiant star RM_1-390 in the Large Magellanic Cloud was made from a 3.6 m telescope at the European Southern Observatory. Spectral resolving power was R=20,000, with a signal-to-noise ratio S/N >
Alexander V. Yushchenko +5 more
doaj +1 more source
Elemental Abundances in the X-Ray Gas of Early-Type Galaxies with XMM and Chandra Observations [PDF]
, 2009 The source of hot gas in elliptical galaxies is thought to be due to stellar mass loss, with contributions from supernova events and possibly from infall from a surrounding environment.
Alex Athey +28 more
core +1 more source