Related papers: A New Contributor to Chemical Evolution in High-Re…
We present a theoretical method for solving the chemical evolution of galaxies, by assuming an instantaneous recycling approximation for chemical elements restored by massive stars and the Delay Time Distribution formalism for the delayed…
In the dense stellar environment of the globular clusters, compact binaries are produced dynamically. Therefore the fraction of type Ia supernovae that explode in globular clusters is expected to be higher than the fraction of mass residing…
To reach a deeper understanding of the origin of elements in the periodic table, we construct Galactic chemical evolution (GCE) models for all stable elements from C (A=12) to U (A=238) from first principles, i.e., using theoretical…
Chemical abundances of iron-peak elements in the red giants of ultra-faint dwarf galaxies (UFD) and dwarf spheroidal galaxies (dSph) are among the best diagnostics in the cosmos to probe the origin of Type Ia Supernovae (SNe Ia). We…
Models of SN driven galactic winds for ellipticals are presented. We assume that ellipticals formed at high redshift and suffered an intense burst of star formation. The role of supernovae of type II and Ia in the chemical enrichment and in…
We review the characteristics of nucleosynthesis in 'Hypernovae', i.e., core-collapse supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). The hypernova yields show the following characteristics: 1) The mass ratio between…
Planetary nebulae are the products of the evolution of low and intermediate mass stars. The chemical property studies of these objects give important information about the elemental abundances as He, O, Ne, Ar, S and their modifications…
Massive BA-type supergiants are among the visually brightest stars in galaxies with active star formation. As such they are versatile tools for studies of stellar and galactochemical evolution. Moreover, they can act as distance indicators…
New abundances of N, O, Na, Mg, Si, Ca, Sc, Ti, Cr, Fe, Sr, Zr, and Ba are presented for 10 A-type supergiants in the SMC, plus upper limits for C. In interpreting the CNO results for constraints on stellar evolution theories, careful…
Elliptical and S0 galaxies dominate the galaxy population in nearby rich clusters such as Coma. Studies of the evolution of the colors, M/L ratios, and line indices of early-type galaxies indicate that they have been a highly homogeneous,…
We examine the characteristics of nucleosynthesis in 'hypernovae', i.e., supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). We carry out detailed nucleosynthesis calculations for these energetic explosions and compare…
Type 1a supernova magnitudes conventionally include an additive parameter called the extinction coefficient. We find that the extinction coefficients of a popular ``gold'' set are well correlated with the deviation of magnitudes from Hubble…
Type Ia supernovae (SNe Ia) correspond to the thermonuclear explosion of a carbon-oxygen white dwarf (C-O WD) star in a binary system, triggered by the accretion of material from another star, or the merger/collision with a secondary WD.…
Ultra diffuse galaxies are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present…
Future measurements of the nature of dark energy using Type Ia supernovae will require a precise characterization of systematic sources of error. Evolutionary effects remain the most uncertain contributor to the overall systematic error…
Intrinsic emission and absorption lines of QSOs provide several independent probes of the metal abundances in QSO environments. They indicate that the metallicities are typically solar or higher out to redshifts z > 4. These results support…
We investigate the chemical evolution of odd-numbered elements such as sodium (Na) and aluminum (Al) during the early epochs of the Galactic halo with the use of a model that reproduces the observed box-shaped distribution of extremely…
We present 3D hydrodynamical simulations aimed to study the dynamical and chemical evolution of the interstellar medium in dwarf spheroidal galaxies. This evolution is driven by the explosions of Type II and Type Ia supernovae, whose…
Recent observations of carbon, sulphur, and titanium isotopes at redshifts z~1 and in the local stellar disc and halo have opened a new window into the study of isotopic abundance patterns and the origin of the chemical elements. Using our…
Recent observations demonstrate that the thin and thick disks of the Galaxy have different chemical abundance trends and evolution timescales. The relative abundances of $\alpha$-elements in the thick Galactic disk are increased relative to…