Browsing by Author "Catalan, Silvia"

Now showing items 1-16 of 16

    • Axions and the cooling of white dwarf stars 

      Isern, J.; Garcia-Berro, E.; Torres, S.; Catalan, Silvia (2008-08-01)
      White dwarfs are the end product of the lives of intermediate- and low-mass stars and their evolution is described as a simple cooling process. Recently, it has been possible to determine with an unprecedented precision ...

    • Axions and the white dwarf luminosity function 

      Isern, J.; Catalan, Silvia; Garcia-Berro, E.; Torres, S. (2009)
      The evolution of white dwarfs can be described as a simple cooling process. Recently, it has been possible to determine with an unprecedented precision their luminosity function, that is, the number of stars per unit volume ...

    • Discovery of a T dwarf + white dwarf binary system 

      Day-Jones, Avril; Pinfield, D.J.; Ruiz, M.; Beaumont, H.; Burningham, B.; Gallardo, J.; Gianninas, A.; Bergeron, P.; Napiwotzki, Ralf; Jenkins, J.S.; Zhang, Z.H.; Murray, D.N.; Catalan, Silvia; Ines Gomes, Joana (2011)
      We present the discovery of the first T dwarf + white dwarf binary system LSPM 1459+0857 AB, confirmed through common proper motion and spectroscopy. The white dwarf is a high proper motion object from the LSPM catalogue ...

    • Discovery of the first white dwarf + T dwarf binary system and the use of white dwarfs as age calibrators 

      Day-Jones, Avril; Pinfield, D.J.; Ruiz, M.; Beaumont, H.; Gallardo, J.; Gianninas, A.; Bergeron, P.; Napiwotzki, Ralf; Jenkins, J.S.; Burningham, B.; Zhang, Z.H.; Jones, H.R.A.; Murray, D.; Catalan, Silvia; Ines Gomes, Joana (American Institute of Physics (AIP), 2010)
      We present the discovery of the first white dwarf + T dwarf binary system. Systems containing a white dwarf and a brown dwarf are rare but can be used to place constraints on the age of the binary, making them valuable ...

    • The impact of mergers in the white dwarf mass distribution 

      Catalan, Silvia; Isern, J.; Garcia-Berro, E.; Hernanz, M. (American Institute of Physics (AIP), 2010)
      The study of the white dwarf mass distribution gives a unique opportunity to obtain information about the amount of mass lost during stellar evolution. Spectroscopic observations of a large number of white dwarfs has allowed ...

    • The initial-final mass relationship from white dwarfs in common proper motion pairs 

      Catalan, Silvia; Isern, J.; Garcia-Berros, E.; Ribas, I.; Prieto, C. Allende; Bonanoss, A. Z. (2008-01)
      Context. The initial-final mass relationship of white dwarfs, which is poorly constrained, is of paramount importance for different aspects of modern astrophysics. From an observational perspective, most of the studies up ...

    • The initial-final mass relationship of white dwarfs in common proper motion pairs 

      Catalan, Silvia; Ribas, I.; Isern, J.; Garcia-Berro, E.; Prieto, C. Allende (Astronomical Society of the Pacific, 2007)
      A promising approach to decrease the uncertainties in the initial-final mass relationship, which is still poorly constrained, is to study white dwarfs for which external constraints are available, for instance, white dwarfs ...

    • The initial-final mass relationship of white dwarfs revisited: effect on the luminosity function and mass distribution 

      Catalan, Silvia; Isern, J.; Garcia-Berro, E.; Ribas, I. (2008-07-11)
      The initial-final mass relationship connects the mass of a white dwarf with the mass of its progenitor in the main sequence. Although this function is of fundamental importance to several fields in modern astrophysics, it ...

    • Stellar chronology with white dwarfs in wide binaries 

      Catalan, Silvia; Garces, A.; Ribas, I.; Isern, J.; Garcia-Berro, E. (Cambridge University Press, 2009)
      White dwarfs are the evolutionary end product of stars with low and intermediate masses. The evolution of white dwarfs can be understood as a cooling process, which is relatively well known at the moment;. For this reason, ...

    • The substellar companion in the eclipsing white dwarf binary SDSS J141126.20+200911.1 

      Littlefair, S.P.; Casewell, S.L.; Parsons, S.G.; Dhillon, V. S.; Marsh, T.R.; Gansicke, B.T.; Bloemen, S.; Catalan, Silvia; Irawati, P.; Hardy, L.K.; Mcallister, M.; Bours, M.C.P.; Richichi, A.; Burleigh, M.R.; Burningham, B.; Breedt, E.; Kerry, P. (2014-12-01)
      We present high time resolution SDSS-g′ and SDSS-z′ light curves of the primary eclipse in SDSS J141126.20+200911.1, together with time-resolved X-Shooter spectroscopy and near-infrared (NIR) JHKs photometry. Our observations ...

    • Testing the initial-final mass relationship of white dwarfs 

      Catalan, Silvia; Isern, J.; Garcia-Berro, E.; Ribas, I. (2009)
      In this contribution we revisit the initial-final mass relationship of white dwarfs, which links the mass of a white dwarf with that of its progenitor in the main-sequence. Although this function is of paramount importance ...

    • Testing the relationship between the masses of white dwarfs and those of their progenitors 

      Isern, J.; Catalan, Silvia; Garcia-Berro, E.; Hernanz, M. (Astronomical Society of the Pacific, 2007)
      The initial final mass relationship of white dwarfs is the function that relates the mass of the white dwarfs with the mass of their main sequence progenitors. At present this function is relatively poorly known from both ...

    • WD0433+270: an old Hyades stream member or an Fe-core white dwarf? 

      Catalan, Silvia; Ribas, I.; Isern, J.; Garcia-Berro, E. (2008-01)
      Context. G39-27/289 is a common proper-motion pair formed by a white dwarf (WD0433+270) and a main-sequence star (BD+26 730) that apparently has been classified as a member of the Hyades open cluster. Previous studies of ...

    • White dwarfs in the ALHAMBRA survey 

      Catalan, Silvia; Isern, J; Garcia-Berro, E; Torres, S; ALHAMBRA Team (Astronomical Society of the Pacific, 2005)
      A new high visual depth survey is presented. New cool white dwarfs will eventually be discovered, which will undoubtely increase the statistical significance of the white dwarf luminosity function. Moreover, by increasing ...

    • White dwarfs in the Capodimonte deep field 

      Silvotti, R.; Catalan, Silvia; Cignoni, M.; Alcala, J. M.; Capaccioli, M.; Grado, A.; Pannella, M. (2009-04)
      Aims. In this article we describe the search for white dwarfs (WDs) in the multi-band photometric data of the Capodimonte deep field survey. Methods. The WD candidates were selected through the V - R-C vs. B-V color-color ...

    • White dwarfs in the Capodimonte Deep Field 

      Catalan, Silvia; Silvotti, R.; Alcala, J. M.; Grado, A.; Capaccioli, M. (Astronomical Society of the Pacific, 2007)
      The goal of this project is to search for white dwarf (WD) candidates in the Capodimonte Deep Field (OACDF) photometric survey and confirm their nature through spectroscopy. In this contribution we discuss our selection ...