217 citations · 1.9k across the 37 of their papers we have counts for
12 papers · 1 filter
Primeval very low-mass stars and brown dwarfs - III. The halo transitional brown dwarfs
Z. H. Zhang, D. J. Pinfield, M. C. Galvez-Ortiz +11
We report the discovery of an esdL3 subdwarf, ULAS J020858.62+020657.0, and a usdL4.5 subdwarf, ULAS J230711.01+014447.1. They were identified as L subdwarfs by optical spectra obt…
The HADES RV Programme with HARPS-N@TNG IV. Time resolved analysis of the Ca ii H&K and Hα chromospheric emission of low-activity early-type M dwarfs
G. Scandariato, J. Maldonado L. Affer, K. Biazzo +22
M dwarfs are prime targets for planet search programs, particularly of those focused on the detection and characterization of rocky planets in the habitable zone. Understanding the…
Extremely fast orbital decay of the black hole X-ray binary Nova Muscae 1991
J. I. González Hernández, L. Suárez-Andrés, R. Rebolo +1
We present new medium-resolution spectroscopic observations of the black hole X-ray binary Nova Muscae 1991 taken with X-Shooter spectrograph installed at the 8.2m-VLT telescope. T…
Magnetic Cycles and Rotation Periods of Late Type Stars from photometric time series
A. Suárez Mascareño, R. Rebolo, J. I. González Hernández
We investigate the photometric modulation induced by magnetic activity cycles and study the relationship between rotation period and activity cycle(s) in late-type (FGKM) stars. We…
Follow-up observations of extremely metal-poor stars identified from SDSS
D. S. Aguado, C. Allende Prieto, J. I. González Hernández +5
The most metal-poor stars in the Milky Way witnessed the early phases of formation of the Galaxy, and have chemical compositions that are close to the pristine mixture from Big Ban…
Stellar parameters of early M dwarfs from ratios of spectral features at optical wavelengths
J. Maldonado, L. Affer, G. Micela +29
(Abridged) Low-mass stars have been recognised as promising targets in the search for rocky, small planets with the potential of supporting life. Doppler search programmes using hi…
A new L-dwarf member of the moderately metal-poor triple system HD 221356
B. Gauza, V. J. S. Béjar, R. Rebolo +10
We report on the discovery of a fourth component in the HD 221356 star system, previously known to be formed by an F8V, slightly metal-poor primary ([Fe/H]=-0.26), and a distant M8…
Be abundances in cool main-sequence stars with exoplanets
E. Delgado Mena, G. Israelian, J. I. González Hernández +2
We present new UVES spectra of a sample of 15 cool unevolved stars with and without detected planetary companions. Together with previous determinations, we study Be depletion and…
Near-infrared Linear Polarization of Ultracool Dwarfs
M. R. Zapatero Osorio, V. J. S. Béjar, B. Goldman +5
We report on near-infrared J- and H-band linear polarimetric photometry of eight ultracool dwarfs (two late-M, five L0-L7.5, and one T2.5) with known evidence for photometric varia…
Beryllium abundances in stars with planets:Extending the sample
M. C. Gálvez-Ortiz, E. Delgado-Mena, J. I. González Hernández +4
Context: Chemical abundances of light elements as beryllium in planet-host stars allow us to study the planet formation scenarios and/or investigate possible surface pollution proc…
Measuring Be depletion in cool stars with exoplanets
Elisa Delgado Mena, Garik Israelian, Jonay I. González Hernández +2
We present new UVES spectra of a sample of 14 mostly cool unevolved stars with planetary companions with the aim of studying possible differences in Be abundance with respect to st…
Near-infrared low-resolution spectroscopy of Pleiades L-type brown dwarfs
G. Bihain, R. Rebolo, M. R. Zapatero Osorio +2
The fundamental properties of brown dwarfs evolve with age. Models describing the evolution of luminosities and effective temperatures, among other physical parameters, can be empi…