Now showing items 1-13 of 13

    • Comparison of theoretical white dwarf cooling timescales (Research Note) 

      Salaris, Maurizio; Althaus, Leandro Gabriel; García-Berro Montilla, Enrique (2013-07)
      Article
      Open Access
      Context. An accurate assessment of white dwarf cooling times is paramount so that white dwarf cosmochronology of Galactic populations can be put on more solid grounds. This issue is particularly relevant in view of the ...
    • Double degenerate mergers as progenitors of high-field magnetic white dwarfs 

      García-Berro Montilla, Enrique; Lorén Aguilar, Pablo; Aznar Siguan, Gabriela; Torres Gil, Santiago; Camacho Díaz, Judit; Althaus, Leandro Gabriel; Córsico, Alejando Hugo; Kulebi, Baybar; Isern Vilaboy, Jordi (2011-04-10)
      Article
      Open Access
      High-field magnetic white dwarfs have been long suspected to be the result of stellar mergers. However, the nature of the coalescing stars and the precise mech anism that produces the magnetic field are still unknown. ...
    • New chemical profiles for the asteroseismolofy of ZZ Ceti stars 

      Althaus, Leandro Gabriel; Córsico, Alejandro Hugo; Bischoff-Kim, A.; Romero, A.D.; Renedo Rouco, Isabel; García-Berro Montilla, Enrique; Miller Bertolami, Marcelo M (2010-07-10)
      Article
      Open Access
      We compute new chemical profiles for the core and envelope of white dwarfs appropriate for pulsational studies of ZZ Ceti stars. These profiles are extracted from the complete evolution of progenitor stars, evolved through ...
    • New cooling sequences for old white dwarfs 

      Renedo Rouco, Isabel; Althaus, Leandro Gabriel; Miller Bertolami, Marcelo M; Romero, A.D.; Córsico, Alejandro Hugo; Rohrmann, Rene Daniel; García-Berro Montilla, Enrique (2010-07)
      Article
      Restricted access - publisher's policy
      We present full evolutionary calculations appropriate for the study of hydrogen-rich DA white dwarfs. This is done by evolving white dwarf progenitors from the zero-age main sequence, through the core hydrogen-burning phase, ...
    • Nucleosynthesis during the merger of white dwarfs and the origin of R Coronae Borealis stars 

      Longland, Richard Leigh; Lorén Aguilar, Pablo; José Pont, Jordi; García-Berro Montilla, Enrique; Althaus, Leandro Gabriel; Isern Vilaboy, Jordi (2011-08-20)
      Article
      Restricted access - publisher's policy
      Many hydrogen-deficient stars are characterized by surface abundance patterns that are hard to reconcile with conventional stellar evolution. Instead, it has been suggested that they may represent the result of a merger ...
    • On the fate of extremely low metallicity stars 

      Gil Pons, Pilar; Gutiérrez Cabello, Jordi; García-Berro Montilla, Enrique; Althaus, Leandro Gabriel (2008)
      Article
      Open Access
      We have computed and analyzed the evolution of intermediate-mass stars of metallicity Z = 10−5 from the main sequence until the early stages of the TP-(S)AGB phase. In order to check the influence of mixing we have ...
    • On the origin of high-field magnetic white dwarfs 

      García-Berro Montilla, Enrique; Torres Gil, Santiago; Lorén Aguilar, Pablo; Aznar Siguan, Gabriela; Camacho Díaz, Judit; Kulebi, Baybar; Isern Vilaboy, Jordi; Althaus, Leandro Gabriel; Corsico, Alejandro H. (Astronomical Society of the Pacific, 2013-01-01)
      Conference lecture
      Open Access
      Every two years, white dwarf researchers and enthusiasts meet to exchange their knowledge and discuss recent developments in white dwarf theory and observations. These proceedings are from the 18th European White Dwarf ...
    • Revisiting the theoretical DBV (V777 Her) instability strip: The MLT theory of convection 

      Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Miller Bertolami, Marcelo M; García-Berro Montilla, Enrique (2009-06-01)
      Article
      Restricted access - publisher's policy
      We reexamine the theoretical instability domain of pulsating DB white dwarfs (DBV or V777 Her variables). We performed an extensive g-mode nonadiabatic pulsation analysis of DB evolutionary models considering a wide range ...
    • Seismological constraints on the high-gravity DOV stars PG 2131+066 and PG 1707+427 

      Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Miller Bertolami, Marcelo M; García-Berro Montilla, Enrique (2009-06-01)
      Article
      Restricted access - publisher's policy
      A seismological study of the pulsating PG1159 stars PG2131+066 and PG 1707+427 is presented. We perform extensive adiabatic computations of g-mode pulsation periods of PG1159 evolutionary models with stellar masses ranging ...
    • The contribution of oxygen-neon white dwarfs to the MACHO content of the Galactic halo 

      Camacho Díaz, Judit; Torres Gil, Santiago; Isern Vilaboy, Jordi; Althaus, Leandro Gabriel; García-Berro Montilla, Enrique (2007-06-13)
      Article
      Open Access
      Context. The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly ...
    • The impact of chemical differentiation of white dwarfs on thermonuclear supernovae 

      Bravo Guil, Eduardo; Althaus, Leandro Gabriel; García-Berro Montilla, Enrique; Domínguez, Inmaculada (2010-12-16)
      Article
      Open Access
      Aims. Gravitational settling of 22Ne in cooling white dwarfs can affect the outcome of thermonuclear supernovae. We investigate how the supernova energetics and nucleosynthesis are in turn influenced by this process. We ...
    • The white dwarf cooling sequence of NGC 6791: an unique tool for stellar astrophysics 

      García-Berro Montilla, Enrique; Torres Gil, Santiago; Renedo Rouco, Isabel; Camacho Díaz, Judit; Althaus, Leandro Gabriel; Córsico, Alejandro Hugo; Salaris, Maurizio; Isern Vilaboy, Jordi (2011)
      Article
      Open Access
      Context. NGC 6791 is a well-studied, metal-rich open cluster that is so close to us that it can be imaged down to luminosities fainter than that of the termination of its white-dwarf cooling sequence, thus allowing for ...
    • White dwarf mergers and the origin of R coronae borealis stars 

      Lorén Aguilar, Pablo; Longland, Richard Leigh; José Pont, Jordi; García-Berro Montilla, Enrique; Althaus, Leandro Gabriel; Isern-Fontanet, J. (2012)
      Conference report
      Restricted access - publisher's policy
      We present a nucleosynthesis study of the merger of a 0.4 M⊙ helium white dwarf with a 0.8 M⊙ carbon-oxygen white dwarf, coupling the thermodynamic history of Smoothed Particle Hydrodynamics particles with a post-processing ...