相关论文: The origin of carbon: Low-mass stars and an evolvi…

The carbon-enhanced metal-poor (CEMP) stars constitute approximately one fifth of the metal-poor ([Fe/H] ~< -2) population but their origin is not well understood. The most widely accepted formation scenario, invokes mass-transfer of…

Carbon-enhanced metal-poor (CEMP) stars are a unique resource for Galactic archaeology because they probe the properties of the First Stars, early chemical evolution and binary interactions at very low metallicity. Comparing the fractions…

We present a comprehensive theoretical investigation of the evolutionary properties of intermediate-mass stars. The evolutionary sequences were computed from the Zero Age Main Sequence up to the central He exhaustion and often up to the…

The carbon to oxygen ratio in a protoplanetary disk can have a dramatic influence on the compositions of any terrestrial planets formed. In regions of high C/O, planets form primarily from carbonates and in regions of low C/O, the ratio of…

We recently presented a model for the cluster formation efficiency (CFE), i.e. the fraction of star formation occurring in bound stellar clusters. It utilizes the idea that the formation of stars and stellar clusters occurs across a…

Based on our prior accurate determination of fundamental parameters for 36 Galactic A-, F- and G-type supergiants and bright giants (luminosity classes I and II), we undertook a non-LTE analysis of the carbon abundance in their atmospheres.…

Astrochemistry has been widely developed as a power tool to probe physical properties of the interstellar medium (ISM) in various conditions of the Milky Way (MW) Galaxy, and in near and distant galaxies. Most current studies conventionally…

We present the results of binary population simulations of carbon-enhanced metal-poor (CEMP) stars. We show that nitrogen and fluorine are useful tracers of the origin of CEMP stars, and conclude that the observed paucity of very…

Massive stars likely played an important role in the reionization of the Universe, and the formation of the first black holes. Massive stars in low-metallicity environments in the local Universe are reminiscent of their high redshift…

Chemical abundances and abundance ratios measured in galaxies provide precious information about the mechanisms, modes and time scales of the assembly of cosmic structures. Yet, the nucleogenesis and chemical evolution of elements heavier…

Two sets of observational carbon stellar yields for low-and-intermediate mass stars are computed from planetary nebulae abundances derived from C II $\lambda4267$ and C III $\lambda\lambda1906+1909$ lines, respectively. By comparing C/O…

We have compiled composition, luminosity, and binarity information for carbon-enhanced, metal-poor (CEMP) stars reported by recent studies. We divided the CEMP star sample into two classes, having high and low abundances, respectively, of…

Uncertainties in stellar nucleosynthesis and their impact on models of chemical evolution are discussed. Comparing the Type II supernova nucleosynthesis prescriptions from Woosley & Weaver (1995) and Thielemann, Nomoto, & Hashimoto (1996),…

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…

The origin of carbon-enhanced metal-poor (CEMP) stars and their possible connections with the chemical elements produced by the first stellar generations is still highly debated. We briefly review observations of CEMP stars in different…

We explore the kinematics and orbital properties of a sample of 323 very metal-poor stars in the halo system of the Milky Way, selected from the high-resolution spectroscopic follow-up studies of Aoki et al. and Yong et al. The combined…

We have developed a new procedure to search for carbon-enhanced metal-poor (CEMP) stars from the Hamburg/ESO (HES) prism-survey plates. This method employs an extended line index for the CH G-band, which we demonstrate to have superior…

Context. CEMP-no stars are long-lived low-mass stars with a very low iron content, overabundances of carbon and no or minor signs for the presence of s- or r-elements. Although their origin is still a matter of debate, they are often…

We investigate the origin of carbon-enhanced metal-poor (CEMP) stars starting from the recently discovered $\rm [Fe/H]<-7.1$ star SMSS J031300 (Keller et al. 2014). We show that the elemental abundances observed on the surface of SMSS…

The gas present in planet-forming disks typically exhibits strong emission features of abundant carbon and oxygen molecular carriers. In some instances, protoplanetary disks show an elevated C/O ratio above interstellar values, which leads…