Related papers: The effects of binary interactions on parameter de…
A large fraction of massive stars evolve in interacting binary systems, which dramatically modifies the outcome of stellar evolution. We investigated the properties of blue supergiants in binary systems and whether they are suitable for…
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here…
We analyze single-stellar-population (SSP) equivalent parameters for 50 local elliptical galaxies as a function of their structural parameters. These galaxies fill a two-dimensional plane in the four-dimensional space of [Z/H], log t, log…
Populations of massive stars are directly reflective of the physics of stellar evolution. Counting subtypes of massive stars and ratios of massive stars in different evolutionary states have been used ubiquitously as diagnostics of age and…
We have investigated the spectro-photometric properties of the Asymptotic Giant Branch (AGB) stars and their contribution to the integrated infrared emission in simple stellar populations (SSP). Adopting analytical relations describing the…
The mean ages of early-type galaxies obtained from the analysis of optical spectra, give a mean age of 8 Gyr at z = 0, with 40% being younger than 6 Gyr. Independent age determinations are possible by using infrared spectra (5-21 microns),…
Observations show that nearly all star clusters and stellar populations contain blue straggler stars (BSs). BSs in a cluster can significantly enhance the integrated spectrum of the host population, preferentially at short wavelengths, and…
We present a detailed spatial analysis of stellar populations based on long-slit optical spectra in a sample of eight luminous early-type galaxies selected from nearby sparse groups and pairs, three of them may be interacting with a galaxy…
We present robust statistical estimates of the accuracy of early-type galaxy stellar masses derived from spectral energy distribution (SED) fitting as functions of various empirical and theoretical assumptions. Using large samples…
We investigate two-dimensional image decomposition of nearby, morphologically selected early-type galaxies (ETGs). We are motivated by recent observational evidence of significant size growth of quiescent galaxies and theoretical…
Nearby companions alter the evolution of massive stars in binary systems. Using a sample of Galactic massive stars in nearby young clusters, we simultaneously measure all intrinsic binary characteristics relevant to quantify the frequency…
We provide observational evidence that galaxy mergers significantly affect stellar kinematics of early-type galaxies (ETGs) such as specific stellar angular momentum within the half-light radius ($\lambda_{R_e}$) and kinematic misalignment…
Binary stars play a crucial role in our understanding of the formation and evolution of star clusters and their stellar populations. We use Gaia Data Release 3 to homogeneously analyze 78 Galactic open clusters and the unresolved binary…
In this paper we investigate a hitherto unexplored source of potentially significant error in stellar population synthesis (SPS) models, caused by systematic uncertainties associated with the three fundamental stellar atmospheric…
The bottom line of this study is (i) to check whether normal (quiescent) and interacting EGs have a different behavior in the popular diagnostic planes such as Hb vs. [MgFe] (and others); (ii) to seek whether the signature of mergers and/or…
We examine the performance of standard PMS stellar evolution models against the accurately measured properties of a benchmark sample of 26 PMS stars in 13 EB systems. We provide a definitive compilation of all fundamental properties for the…
Context: The technique of matching synthetic spectra computed with theoretical stellar atmosphere models to the observations is widely used in deriving fundamental parameters of massive stars. When applied to binaries, however, these models…
The calibrations of star formation rate (SFR) are prone to be affected by many factors, such as metallicity, initial mass function (IMF), evolutionary population synthesis (EPS) models and so on. In this paper we will discuss the effects of…
In a sample of about 45,700 early-type galaxies extracted from SDSS, we find that the shape, normalization, and dispersion around the mean size-stellar mass relation is the same for young and old systems, provided the stellar mass is…
Synthetic integrated spectral properties of the old Galactic open clusters are studies in this work, where twenty-seven Galactic open clusters of ages >= 1Gyr are selected as the working sample. Based on the photometric observations of…