相关论文: An optimized H_\beta index for disentangling stell…

We present the analysis of the radial gradients of stellar absorption lines in a sample of 32 bulges of edge-on spiral galaxies, spanning nearly the full Hubble sequence (from S0 to Sc types), and a large range of velocity dispersion (from…

By using a one-zone chemical and spectrophotometric evolution model of a disk galaxy undergoing a dusty starburst, we investigate, numerically, the optical spectroscopic properties in order to explore galaxy evolution in distant clusters.…

We take advantage of the publicly available LEGA-C spectroscopic survey to measure the stellar population properties of 140 individual massive and passive galaxies at $z\sim0.7$. We develop and publicly release PyLick, a flexible python…

We present recent progress on quantitative estimation of stellar ages using ind icators such as theoretical evolutionary tracks, rotation, rotation-driven chrom ospheric and coronal activity, and lithium depletion. Our focus is on roughly…

The unprecedented sensitivity and spatial resolution of next generation ground-based extremely large telescopes (ELTs) will open a completely new window on the study of resolved stellar populations. In this paper we study the feasibility of…

The ACS Survey of Galactic Globular Clusters is a Hubble Space Telescope (HST) Treasury program designed to provide a new large, deep and homogeneous photometric database. Based on observations from this program, we have measured precise…

In this paper we present measurements of velocity dispersions and Lick indices for 509 galaxies in the local Universe, based on high signal-to-noise, long slit spectra obtained with the 1.52 m ESO telescope at La Silla. The conversion of…

We consider the depletion of primordial deuterium in the interior of substellar objects as a function of mass, age and absolute magnitude in several photometric passbands. We characterize potential spectroscopic signatures of deuterium in…

We present a new catalog and results for the cluster system of the starburst galaxy NGC 4449 based on multi-band imaging observations taken as part of the LEGUS and Halpha-LEGUS surveys. We improve the spectral energy fitting method used to…

We construct mock galaxy catalogues to analyse clustering properties of a Lambda cold dark matter (LCDM) universe within a cosmological dark matter simulation of sufficient resolution to resolve structure down to the scale of dwarfs. We…

Determining the sequence of events in the formation of stars and planetary systems and their time-scales is essential for understanding those processes, yet establishing ages is fundamentally difficult because we lack direct indicators. In…

We exploit the most robust, old, and cosmology-independent age estimates of individual stars from Gaia DR3 to place a lower bound on the age of the Universe, $t_U$. These constraints can serve as an anchor point for any cosmological model,…

Traditional studies of stellar clusters in external galaxies use surface photometry and therefore focus on systems that are still bright and compact enough to be separated from the stellar background. Consequently, the latter stages of…

We use the framework developed as part of the MESA Isochrones and Stellar Tracks (MIST) project to assess the utility of several types of observables in jointly measuring the age and 1D stellar model parameters in star clusters. We begin…

We present high signal-to-noise Keck spectra for 10 globular clusters associated with the giant Fornax elliptical NGC 1399, and compare measured line indices with current stellar population models. Our data convincingly demonstrate, for the…

Globular cluster ages provide both an important test of models of globular cluster formation and a powerful method to constrain the assembly history of galaxies. Unfortunately, measuring the ages of unresolved old stellar populations has…

Stellar chromospheric activity serves as a valuable proxy for estimating stellar ages, though its applicable range and accurate functional form are still debated. In this study, utilizing the LAMOST spectra we compiled a catalog of open…

Omega Centauri is a peculiar Globular Cluster formed by a complex stellar population. To shed light on this, we studied 172 stars belonging to the 5 SGBs that we can identify in our photometry, in order to measure their [Fe/H] content as…

We calculate the ages, orbits and phase-space coordinates for a sample of $\sim$4 million LAMOST and Gaia stars. The ages are crossmatched and compared with values from two other popular age catalogs which derive the ages using different…

We present absorption line strength maps of a sample of 24 representative early-type spiral galaxies, mostly of type Sa, obtained as part of the SAURON survey of nearby galaxies using our custom-built integral-field spectrograph. Using…