Related papers: Calcium Triplet Synthesis
We present non-local thermodynamic equilibrium (NLTE) line formation calculations for Ca I and Ca II in B-F stars. The sign and the magnitude of NLTE abundance corrections depend on line and stellar parameters. We determine calcium…
We constrain the stellar population properties of a sample of 52 massive galaxies, with stellar mass log Ms>10.5, over the redshift range 0.5<z<2 by use of observer-frame optical and near-infrared slitless spectra from HST's ACS and WFC3…
The vertical metallicity gradient of the Galactic disk offers valuable insights into the disk's formation and chemical evolution over time. We utilized the LAMOST-LRS young stellar sample to investigate this gradient and found that it…
We use very deep near-infrared photometry of the Hubble Deep Field South taken with ISAAC/VLT to identify a population of high redshift galaxies with rest- frame optical colors similar to those of nearby galaxies. The galaxies are chosen by…
We have observed the largest optical spectra sample of 74 blue compact galaxies. Stellar population properties of them were derived by comparing the equivalent widths of strong absorption features and continuum colors, using a method of…
We derive ages, metallicities, and individual element abundances of early- and late-type galaxies (ETGs and LTGs) out to 1.5 R$_e$. We study a large sample of 1900 galaxies spanning $8.6 - 11.3 \log M/M_{\odot}$ in stellar mass, through key…
We present a novel statistical algorithm, Stellar Ages, which currently infers the age, metallicity, and extinction posterior distributions of stellar populations from their magnitudes. While this paper focuses on these parameters, the…
Radial trends of stellar populations in galaxies provide a valuable tool to understand the mechanisms of galaxy growth. In this paper, we present the first comprehensive analysis of optical-optical and optical-NIR colours, as a function of…
Analytical models of chemical evolution, including inflow and outflow of gas, are important tools to study how the metal content in galaxies evolves as a function of time. In this work, we present new analytical solutions for the evolution…
We present evolutionary stellar population synthesis models to predict the spectrum of a single-metallicity stellar population, with a spectral sampling of 0.3 A in five spectral regions between 3700 and 5000 A. The models, which are…
Stellar ages are an important parameter to study the chemical evolution of the Galaxy. In recent years, several studies have established the existence of a relationship between chemical clocks and stellar ages. The [Y/Mg] clock is a…
We report on the identification of the old stellar population galaxy candidates at z > 5. We developed a new infrared color selection scheme to isolate galaxies with the strong Balmer breaks at z > 5, and applied it to the ultra-deep and…
We present the analysis of Lick absorption-line indices from three separate long-slit spectroscopic observations of the nearby isolated elliptical galaxy NGC 821. The three data sets present a consistent picture of the stellar population…
The efficient use of near-IR data in studies of external stellar populations depends on our ability to recognize the nature of the predominant sources of light, and to interprete these findings in terms of age and metallicity. Here we focus…
Near-infrared (hereafter NIR) data may provide complementary information to the traditional optical population synthesis analysis of unresolved stellar populations because the spectral energy distribution of the galaxies in the 1-2.5\mum…
A VLT/MUSE population synthesis study of metallicities in the nuclear star-forming rings of four disk galaxies (NGC 613, NGC 1097, NGC 3351, NGC 7552) is presented. Disentangling the spectral contributions of young and old stellar…
As part of a larger program to identify and characterize possible low-redshift analogs to massive compact red galaxies found at high redshift, we have examined the morphologies of three low-redshift compact galaxies drawn from the sample of…
The color-magnitude diagrams (CMDs) of three intermediate-age LMC clusters, NGC 2173, SL556 and NGC2155 are analyzed to determine their age and metallicity basing on Padova stellar models. Synthetic CMDs are compared with cluster data. The…
We present results of model atmosphere/line formation calculations which quantitatively test how the 21 classical and four higher-order Balmer-line Lick/IDS indices (Worthey et al. 1994; Worthey & Ottaviani 1997) depend on individual…
We use our new stellar population models, which include effects from variable element abundance ratios, to model the Ca4227 absorption line indices of early-type galaxies (Trager et al.), and to derive calcium element abundances. We find…