Non-LTE calculations of H-alpha line profiles are presented and applied to derive rotational velocities from high-resolution spectra of DA white dwarfs. This...
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PublicationNon-local thermodynamic equilibrium line profiles, rotation, and magnetic fields in seven DA white dwarfs
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PublicationObservation of a variable, ZZ Ceti white dwarf: GD154
The ZZ Ceti stars form a class of variable white dwarfs: the hydrogen dominated atmosphere ones, which do pulsate in an instability strip in the effective...
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PublicationOn the O/Fe versus Fe/H relationship and the progenitors of type I supernovae
The new observational O/Fe versus Fe/H abundance relationship for halo stars is studied in terms of several models of chemical evolution for the solar...
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PublicationPreliminary Target Selection for the DESI Milky Way Survey (MWS)
The DESI Milky Way Survey (MWS) will observe ≥8 million stars between 16 < r < 19 mag, supplemented by observations of brighter targets under poor observing...
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PublicationRed giant stragglers and He white dwarfs in galactic globulars
The evolutionary scenario concerning the production and the cooling of He white dwarfs is revisited and discussed. We show that, for a given star metallicity...
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NewsScientists discover the first pulsating white dwarf in an eclipsing binary system
An international research, led by scientists from the University of Sheffield and with the participation of the Instituto de Astrofísica de Canarias, has...
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PublicationStrong Carbon Features and a Red Early Color in the Underluminous Type Ia SN 2022xkq
We present optical, infrared, ultraviolet, and radio observations of SN 2022xkq, an underluminous fast-declining Type Ia supernova (SN Ia) in NGC 1784 (D ≈ 31...
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NewsTESS, Spitzer and the GTC detect a planet orbiting a white dwarf for the first time
With data from NASA’s TESS satellite, from the now retired Spitzer Space Telescope, and the Gran Telescopio Canarias (GTC) an international team of astronomers...
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PublicationThe early nucleosynthesis of O and Fe
The new observational O/Fe vs Fe/H relationship in halo dwarfs is analyzed in terms of a model of chemical evolution for the solar neighborhood. The role of...