Related papers: The PGPUC horizontal branch evolutionary tracks
The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment. The most studied model today claims that the ejecta of Asymptotic Giant Branch (AGB) stars of high mass…
I briefly introduce a database of models that describe the evolution of star clusters in several broad-band photometric systems. Models are based on the latest Padova stellar evolutionary tracks - now including the alpha-enhanced case and…
Theoretical integrated spectrophotometric quantities, such as spectral line indices in the Lick system (Hbeta, Mg2, Mg b, Fe5270, Fe5335), broadband color indices (in the UBVRIHK and Washington CMT1 bandpasses), and surface brightness…
In this paper we present preliminary results from our HST project aimed at exploring the connection between the stellar dynamics and stellar evolution in the cores of high-density globular clusters. We illustrate the discovery of horizontal…
Understanding the internal structure of core helium burning (CHeB) stars is crucial for evaluating transport processes in nuclear-burning regions, constructing accurate stellar population models, and assessing nucleosynthesis processes that…
We study the distribution of exoplanets around main sequence (MS) stars and apply our results to the binary model for the formation of extreme horizontal branch (EHB; sdO; sdB; hot subdwarfs) stars. By Binary model we refer both to stellar…
Context. Globular clusters (GCs) are suggested to host many stellar-mass black holes (BHs) at their centers, thus resulting in ideal testbeds for BH formation and retention theories. BHs are expected to play a major role in GC structural…
Context: Studying the motions on the solar surface is fundamental for understanding how turbulent convection transports energy and how magnetic fields are distributed across the solar surface. Aims: From horizontal velocity measurements all…
We present the far-UV (FUV) photometry of images acquired with UVIT on AstroSat to probe the horizontal branch (HB) population of the Galactic globular cluster NGC 2298. UV-optical color-magnitude diagrams (CMDs) are constructed for member…
Twenty years ago, Burstein et al. (1984)suggested that strong CN and Hbeta absorption meant younger ages among globular clusters in the Andromeda galaxy (M31), unless blue stars above the main-sequence turnoff or on the horizontal branch…
The globular cluster omega Centauri contains the largest known population of very hot horizontal branch (HB) stars. We have used the Hubble Space Telescope to obtain a far-UV/optical color-magnitude diagram of three fields in omega Cen. We…
We explore the evolution of collisionally merged stars in the blue straggler region of the HR diagram. The starting models for our stellar evolution calculations are the results of the smoothed particle hydrodynamics (SPH) simulations of…
Helium has been proposed as the key element to interpret the observed multiple main sequences (MS), subgiant branches (SGB) and red giant branches (RGB), as well as the complex horizontal branch (HB) morphology in Globular Clusters (GC).…
The analysis of solar-like oscillations for stars belonging to a binary system provides a unique opportunity to probe the internal stellar structure and to test our knowledge of stellar physics. Such oscillations have been recently observed…
Evolutionary synthesis models for star clusters of various metallicities including gaseous emission during the lifetime of the ionising stars are used to model star cluster systems comprising two populations: an old metal-poor globular…
In this letter we report on the detection of a new feature in the complex structure of the horizontal branch (HB) of the Galactic globular cluster NGC 6752. In the U vs. (U-V) plane, the HB shows a discontinuity (``jump'') at U-V ~= -1.0…
The frequencies of gravity mode oscillations are determined by the chemical, thermal, and structural properties of stellar interiors, facilitating the study of internal mixing mechanisms in stars. We investigate the impact of…
Observations of star formation rates (SFRs) in galaxies provide vital clues to the physical nature of the Hubble sequence, and are key probes of the evolutionary properties of galaxies. The focus of this review is on the broad patterns in…
Stellar ages are critical for understanding the temporal evolution of a galaxy. We calculate the ages of over 6000 red giant branch stars in the Large Magellanic Cloud (LMC) observed with SDSS-IV / APOGEE-S. Ages are derived using…
We present a large and updated stellar evolution database for low-, intermediate- and high-mass stars in a wide metallicity range, suitable for studying Galactic and extragalactic simple and composite stellar populations using population…