Related papers: Stellar Parameter Determination from Photometry us…
The combination of photometry, spectroscopy and spectropolarimetry of the chemically peculiar stars often aims to study the complex physical phenomena such as stellar pulsation, chemical inhomogeneity, magnetic field and their interplay…
Evolutionary synthesis models are the prime method to construct models of stellar populations, and to derive physical parameters from observations. One of the assumptions for such models so far has been the time-independence of the stellar…
We discuss new photometry from high-resolution images of 7 intermediate-age (1-2 Gyr) star clusters in the Large Magellanic Cloud taken with the Advanced Camera for Surveys on board the Hubble Space Telescope. We fit color-magnitude…
Aims. The main purpose is to map the radial variation of the stellar space density for the young stellar population in the Galactic anticenter direction in order to understand the structure and location of the Perseus spiral arm. Methods. A…
We illustrate the application of high precision Stromgren uvby photometry to open and globular clusters (GCs). It is shown how such data can be used to determine cluster ages, independent of distance and only weakly dependent on reddening.…
We present the first results of a large ACS Survey of Galactic globular clusters. This Hubble Space Telescope (HST) Treasury project is designed to obtain photometry with S/N > ~10 for main sequence stars with masses > ~0.2Msun in a sample…
Stellar evolution theory has been extraordinarily successful at explaining the different phases under which stars form, evolve and die. While the strongest constraints have traditionally come from binary stars, the advent of…
We measure radial stellar age gradients in the relatively isolated gas-rich dwarf irregular WLM, combining JWST NIRCam and NIRISS imaging with six archival Hubble fields over semi-major axis equivalent distances of…
Searches for supernovae (SNe) progenitors have relied on a direct detection of the star in fortuitous pre-explosion images. We propose an alternative method, using a combination of photometric stellar population fitting alongside…
We present results exploring the role that probabilistic deep learning models can play in cosmology from large-scale astronomical surveys through photometric redshift (photo-z) estimation. Photo-z uncertainty estimates are critical for the…
We present a ground-based time-series photometric study of stellar variability in four intermediate- to old-age open clusters NGC 2192, NGC 2266, NGC 2509, and IC 1369 based on high-cadence Cousins R-band observations obtained with the 0.6…
We present an original study of the dwarf starburst galaxy NGC 4214. We use archival optical and UV images obtained with WFPC2 and STIS on-board the Hubble Space Telescope. We explain the process followed to obtain high-quality photometry…
Spectroscopic surveys require fast and efficient analysis methods to maximize their scientific impact. Here we apply a deep neural network architecture to analyze both SDSS-III APOGEE DR13 and synthetic stellar spectra. When our…
Spitzer IRAC mid-infrared photometry is presented for the globular cluster (GC) systems of the NGC 5128 ("Centaurus A") and NGC 4594 ("Sombrero") galaxies. Existing optical photometric and spectroscopic are combined with this new data in a…
We present JWST/NIRCam observations of a strongly-lensed, multiply-imaged galaxy at $z=6.072$, with magnification factors >~20 across the galaxy. We perform a spatially-resolved analysis of the physical properties at scales of ~200 pc,…
The new generation of deep photometric surveys requires unprecedentedly precise shape and photometry measurements of billions of galaxies to achieve their main science goals. At such depths, one major limiting factor is the blending of…
Over its lifespan, the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) will monitor millions of supernovae (SNe) from explosion to oblivion, yielding an unprecedented ugrizy photometric dataset on their late-time evolution.…
Atmospheric and evolutionary models for low-mass stars rely on approximate assumptions on the physics of the stellar structure and the atmospheric radiative transfer. This leads to biased theoretical predictions on the photospheric Spectral…
Planetary nebulae (PNe) are pivotal for advancing our knowledge of stellar evolution and galactic chemical enrichment. Recent progress in surveys and data analysis has revolutionized PN research, leading to the discovery of new objects and…
Asteroseismology of bright stars with well-determined properties from parallax measurements and interferometry can yield precise stellar ages and meaningful constraints on the composition. We substantiate this claim with an updated…