Andrea Mejías
A5072874753- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astrophysics and Star Formation Studies
Universidad Andrés Bello
2019-2023
Millennium Institute of Astrophysics
2019
Context. The ESO public survey VISTA Variables in the Vía Láctea (VVV) surveyed inner Galactic bulge and adjacent southern disk from 2009–2015. Upon its conclusion, complementary VVV extended (VVVX) has expanded both temporal as well spatial coverage of original area, widening it 562 to 1700 sq. deg., providing additional epochs JHK s filters 2016–2023. Aims. With completion VVVX observations during first semester 2023, we present here observing strategy, a description data quality access,...
The ESO public survey VISTA Variables in the V\'ia L\'actea (VVV) surveyed inner Galactic bulge and adjacent southern disk from $2009-2015$. Upon its conclusion, complementary VVV eXtended (VVVX) has expanded both temporal as well spatial coverage of original area, widening it $562$ to $1700$ sq. deg., providing additional epochs $JHK_{\rm s}$ filters $2016-2023$. With completion VVVX observations during first semester 2023, we present here observing strategy, a description data quality...
Red dwarf stars, which represent 75% of stars in the Milky Way, can be studied great detail solar neighborhood where sample is more complete. We intend to better characterize red candidates selected from Gaia Catalog Nearby Stars using optical and near-infrared photometry VVVX Survey, DECaPS, Pan-STARRS, WISE. performed a cross-matching procedure among positions color-selected M dwarfs Survey EDR3 sub-catalog nearby stars. explored their stellar parameters spectral types VOSA. Radii were...
Abstract We present an analysis of the relative age distribution Milky Way halo, based on samples blue horizontal-branch (BHB) stars obtained from Panoramic Survey Telescope and Rapid Response System Galaxy Evolution Explorer photometry, as well a Sloan Digital Sky spectroscopic sample. A machine-learning approach to selection BHB is developed, using support vector classification, with which we produce chronographic maps halo out 40 kpc Galactic center. identify characteristic break in...
ABSTRACT We present the discovery and multiwavelength characterization of VVV J1438-6158 AB, a new field wide-binary system consisting $4.6^{+5.5}_{-2.4}~{\rm Gyr}$ $T_{\rm eff} = 9500\pm 125~\mathrm{ K}$ DA white dwarf (WD) 2400\pm 50~\mathrm{ M8 ultracool (UCD). The projected separation is $a 1236.73~{\rm au}$ ($\sim 13.8\, \mathrm{ arcsec}$), although along line sight towards Scorpius–Centaurus stellar association, AB likely to be star, from kinematic 6D probabilistic analysis. estimated...
We present the discovery and multi-wavelength characterisation of VVV J1438-6158 AB, a new field wide-binary system consisting 4.6(+5.5-2.4) Gyr Teff = 9500+/-125 K DA white dwarf (WD) 2400+/-50 M8 ultracool (UCD). The projected separation is 1236.73 au (~13.8"), although along line-of-sight towards Scorpius-Centaurus (Sco-Cen) stellar association, AB likely to be star, from kinematic 6D probabilistic analysis. estimated physical, dynamical parameters both components via interpolations with...