Anisotropic crystal structure of magnetized neutron star crust
| Autor: | A. A. Kozhberov, D. A. Baiko |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
Physics Condensed matter physics Phonon FOS: Physical sciences Astronomy and Astrophysics Astrophysics Magnetar 01 natural sciences Instability Magnetic field Crystal Neutron star Space and Planetary Science Liquid crystal 0103 physical sciences Astrophysics - High Energy Astrophysical Phenomena 010306 general physics Anisotropy 010303 astronomy & astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 470:517-521 |
| ISSN: | 1365-2966 0035-8711 |
| Popis: | Although crystallized neutron star crust is responsible for many fascinating observational phenomena, its actual microscopic structure in tremendous gravitational and magnetic fields is not understood. Here we show that in a non-uniform magnetic field, three-dimensional ionic Coulomb crystals comprising the crust may stretch or shrink while their electrostatic pressure becomes anisotropic. The pressure depends non-linearly on the magnitude of the stretch, so that a continuous magnetic field evolution may result in an abrupt crystal elongation or contraction. This may provide a trigger for magnetar activity. A phonon mode instability is revealed, which sets the limits of magnetic field variation beyond which the crystal is destroyed. These limits sometimes correspond to surprisingly large deformations. It is not known what happens to crust matter subject to a pressure anisotropy exceeding these limits. We hypothesize that the ion system then possesses a long-range order only in one or two dimensions, that is becomes a liquid crystal. 12 pages; submitted |
| Databáze: | OpenAIRE |
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