Mesospheric sodium monitoring for laser guide star
The experimental study of sodium layer is relevant to fields such as adaptive optics, in particular for laser guide star generation. We have developed an...
This chapter reviews our current knowledge of metal-poor ultracool dwarfs with spectral types later than M7. The current census of M, L, and T subdwarfs is...
Metal-poor solar-type stars spectroscopy and masses (Sousa+, 2011)
The stellar parameters were determined using an LTE analysis based on equivalent widths (EW) of iron lines and by imposing excitation and ionization equilibrium...
Metal-poor ultracool dwarfs (ultracool subdwarfs, including very-low-mass stars and brown dwarfs) are tracers of the pristine chemical composition at early...
Metal-rich end of galactic chemical evolution: oxygen abundances from [OI] 6300, OI 7771 5 and near-UV OH.
We present a detailed and uniform study of oxygen abundances in a large set of 155 metal-rich dwarfs. EW measurements were carried out for the [OI] 6300 Å line...
Spectroscopic data of two relatively [O III]-luminous -PNe have been obtained with the 10.4-m Gran Telescopio Canarias. M174 and M2496 are each ˜1 degree from...
Metallicities and Kinematics for Dwarf Spheroidals in the Local Group
We present the first results of CaII triplet observations from VLT/FLAMES for Sculptor, Fornax and Sextans dSphs. For each galaxy, we obtained accurate velocity...
Metallicity dependence of some parameters of Cepheids
Dependence of phenomenological properties of Cepheids on the heavy element abundance is studied. It is found that the amplitude of the pulsation depends on the...