Do weak magnetic fields prevent hydrogen from accreting onto metal-line white dwarf stars?
نویسندگان
چکیده
منابع مشابه
Do weak magnetic fields prevent hydrogen from accreting onto metal - line white dwarf stars ? ⋆
The widely accepted assumption is that metals detected in the spectra of a few cool helium-rich white dwarfs cannot be of primordial origin and therefore must be accreted from the interstellar medium. However, the observed abundances of hydrogen are much too low to be compatible with the high accretion rates inferred from metal accretion. Hydrogen accretion is therefore suppressed compared to m...
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Models of magnetospheric accretion on to classical T Tauri stars often assume that the stellar magnetic field is a simple dipole. Recent Zeeman-Doppler imaging studies of V2129 Oph and BP Tau have shown however that their magnetic fields are more complex. V2129 Oph is a high mass T Tauri star and despite its young age is believed to have already developed a radiative core. In contrast to this, ...
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Models of magnetospheric accretion on to classical T Tauri stars often assume that stellar magnetic fields are simple dipoles. Recently published surface magnetograms of BP Tau and V2129 Oph have shown, however, that their fields are more complex. The magnetic field of V2129 Oph was found to be predominantly octupolar. For BP Tau the magnetic energy was shared mainly between the dipole and octu...
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We have conducted a survey of 61 southern white dwarfs searching for magnetic fields using Zeeman spectropolarimetry. Our objective is to obtain a magnetic field distribution for these objects and, in particular, to find white dwarfs with weak fields. We found one possible candidate (WD 0310−688) that may have a weak magnetic field of −6.1±2.2 kG. Next, we determine the fraction and distributio...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2004
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20041183