Astronomers of the SAO together with an international group of scientists
have proposed an explanation to the long-standing
mystery of why magnetic fields are more common amongst cool white dwarf
stars than amongst young and hotter ones. In the framework of theoretical
analysis of observations (including observations from the BTA) the authors
have shown that strongest magnetic fields are sufficient to suppress
convection over the entire surface in cool magnetic white dwarfs, which
inhibits their cooling evolution relative to weakly magnetic and
non-magnetic ones. As the result magnetic white dwarfs demonstrate
excess in their frequencies in the temperature range below 14000K.
The authors also show that the strongly magnetic white dwarfs are
of the oldest stars of the Galaxy originated from intermediate-mass
relic stars.
Published:
G.Valyavin, D.Shulyak, G.A.Wade, K.Antornyuk and 16 co-authors,
2014, Nature, doi:10.1038/nature13836
Contact - Gennady Valyavin
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Fig.1.
Computer visualization of the reconstructed magnetic-field and
temperature (brightness) distribution on the surface of the magnetic dwarf
WD1953-011
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