Related papers: Magnetic field evolution for crystallization-drive…
Recent surveys of close white dwarf binaries as well as single white dwarfs have provided evidence for the late appearance of magnetic fields in white dwarfs, and a possible generation mechanism a crystallization and rotation-driven dynamo…
A significant fraction of white dwarfs possess a magnetic field with strengths ranging from a few kG up to about 1000 MG. However, the incidence of magnetism varies when the white dwarf population is broken down into different spectral…
Observations of magnetic A, B and O stars show that the poloidal magnetic flux per unit mass has an upper bound of 10^-6.5 G cm^2/g. A similar upper bound is found for magnetic white dwarfs even though the highest magnetic field strengths…
About half of white dwarfs (WDs) evolve to the DC state as they cool; the others become DQ or (temporarily?) DZ WDs. The recent magnetic survey of the local 20 pc volume has established a high frequency of magnetic fields among WDs older…
Early-type stars show a bimodal distribution of magnetic field strengths, with some showing very strong fields ($\gtrsim 1\,\mathrm{kG}$) and others very weak fields ($\lesssim 10\,\mathrm{G}$). Recently, we proposed that this reflects the…
Ultramassive white dwarfs (UMWDs; defined by masses $\gtrsim 1.1\,{\rm M}_\odot$) are prime targets for seismology, because they pass through the ZZ Ceti instability strip at the same time that their cores crystallize. Recent studies…
Assuming that white dwarf (WD) magnetic fields are generated by a crystallization- and rotation-driven dynamo, the impact of the late appearance of WD magnetic fields in cataclysmic variables (CVs) has been shown to potentially solve…
Isolated magnetic white dwarfs have field strengths ranging from kilogauss to gigagauss, and constitute an interesting class of objects. The origin of the magnetic field is still the subject of a hot debate. Whether these fields are fossil,…
The magnetic fields of spiral galaxies are so strong that they cannot be primordial. Their typical values are over one billion times higher than any value predicted for the early Universe. Explaining this immense growth and incorporating it…
A dynamo mechanism driven by differential rotation when stars merge has been proposed to explain the presence of strong fields in certain classes of magnetic stars. In the case of the high field magnetic white dwarfs (HFMWDs), the site of…
We discuss the evolution of the magnetic field of an accreting white dwarf. We first show that the timescale for ohmic decay in the liquid interior is 8 to 12 billion years for a dipole field, and 4 to 6 billion years for a quadrupole…
Chemically peculiar Ap and Bp stars host strong large-scale magnetic fields in the range of $200$~G up to $30$~kG, which are often considered to be the origin of fossil magnetic fields. We assess the evolution of such fossil fields during…
The origin of magnetic fields in white dwarfs remains a fundamental unresolved problem in stellar astrophysics. In particular, the very different fractions of strongly (exceeding 1 MG) magnetic white dwarfs in evolutionarily linked…
Rotation has a number of important effects on the evolution of stars. It decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes. We have adapted the Cambridge stellar…
Using a set of cosmological hydro-dynamical simulations, we constrained the properties of primordial magnetic fields by studying their impact on the formation and evolution of dwarf galaxies. We performed a large set of simulations (8 dark…
Magnetic fields can play an important role in stellar evolution. Among white dwarfs, the most common stellar remnant, the fraction of magnetic systems is more than 20 per cent. The origin of magnetic fields in white dwarfs, which show…
White dwarfs are excellent research laboratories as they reach temperatures, pressures, and magnetic fields that are unattainable on Earth. To better understand how these three physical parameters interact with each other and with other…
Numerical simulations have shown that the strength of planetary magnetic fields depends on the convective energy flux emerging from planetary interiors. Here we model the interior structure of gas giant planets using \texttt{MESA}, to…
The origin of strong magnetic fields in white dwarfs has been a puzzle for decades. Recently, a dynamo mechanism operating in rapidly rotating and crystallizing white dwarfs has been suggested to explain the occurrence rates of strong…
Wickramasinghe et al. (2014) and Briggs et al. (2015) have proposed that the strong magnetic fields observed in some single white dwarfs (MWDs) are formed by a dynamo driven by differential rotation when two stars, the more massive one with…