White Dwarfs

heic0516b.jpg

 

 

 

 

 

 

 

 

 

 

An artist's impression of Sirius A and Sirius B. Credit: NASA, ESA and G. Bacon (STScI)

The principal academic members of the White Dwarf subgroup are Professor Martin Barstow and Dr Matt Burleigh, who holds a PPARC Advanced Fellowship. There are currently three PhD students in the group and there are close links with the Brown Dwarf research activity, led by Dr Richard Jameson. We collaborate extensively with similar research groups in other institutions, including the Universities of Warwick, Keele and Hertfordshire in the UK, with Tubingen and Kiel in Europe and Arizona, Johns Hopkins and Villanova in the USA. In particular, we work closely with Ivan Hubeny (Steward Observatory) in the development of hot white dwarf model atmospheres and synthetic spectra.

White dwarf stars play a key role in some of the most important astronomical questions of our day. Their space and luminosity distributions help map out the history of star formation in the Galaxy and can be used to determine the age of the disk. They are also believed to play a significant role in the production of the cosmologically important type Ia supernovae, through stellar mergers or mass transfer. White dwarfs have an intimate relationship with interstellar gas, a fundamental component of the Milky Way and other galaxies. The local interstellar medium (LISM) is close enough to us for detailed examination of its composition and structure, which tells us about the evolution of the Universe and our galaxy. Production of white dwarfs in the disk substantially enriches the content of the local ISM, contributing significantly to the total cosmic abundance of metals, particularly CNO.

The white dwarf sub-group pursues a broad research programme of several inter-related topics aimed at understanding the fundamental parameters of white dwarfs and their interaction with the local interstellar medium (LISM), including:

  • Studies of white dwarfs in detached binary systems to test binary evolution models, the theoretical WD mass radius relation and the WD initial-final mass relation.
  • Measurement of heavy element abundances in white dwarf photospheres, using far-UV and EUV spectra, to study the physical processes that affect white dwarf evolution.
  • Continuation of a search for planetary companions to white dwarfs and extension to a more general search for low mass companions (including brown dwarfs and M dwarfs) and circumstellar material.

For further information and for current research, please see our white dwarf pages.

Share this page: