THE EVOLUTION OF THE FOSSIL LARGE-SCALE MAGNETIC FIELD IN TURBULENT ACCRETION DISKS OF YOUNG STARS
Section: STARS AND THE INTERSTELLAR MEDIUM
Authors:
1.
Chelyabinsk State University
2.
Ural Federal University
Saint-Petersburg University
Chelyabinsk State University
Saint-Petersburg University
Chelyabinsk State University
Type:
Сonference article
Published:
27.12.2024
Subject area:
UDK 52 Астрономия. Геодезия
UDK 53 Физика
UDK 520 Инструменты, приборы и методы астрономических наблюдений, измерений и анализа
UDK 521 Теоретическая астрономия. Небесная механика. Фундаментальная астрономия. Теория динамической и позиционной астрономии
UDK 523 Солнечная система
UDK 524 Звезды и звездные системы. Вселенная Солнце и Солнечная система
UDK 52-1 Метод изучения
UDK 52-6 Излучение и связанные с ним процессы
GRNTI 41.00 АСТРОНОМИЯ
GRNTI 29.35 Радиофизика. Физические основы электроники
GRNTI 29.31 Оптика
GRNTI 29.33 Лазерная физика
GRNTI 29.27 Физика плазмы
GRNTI 29.05 Физика элементарных частиц. Теория полей. Физика высоких энергий
OKSO 03.06.01 Физика и астрономия
OKSO 03.05.01 Астрономия
OKSO 03.04.03 Радиофизика
BBK 2 ЕСТЕСТВЕННЫЕ НАУКИ
BBK 223 Физика
TBK 614 Астрономия
TBK 6135 Оптика
BISAC SCI004000 Astronomy
BISAC SCI005000 Physics / Astrophysics
UDK 53 Физика
UDK 520 Инструменты, приборы и методы астрономических наблюдений, измерений и анализа
UDK 521 Теоретическая астрономия. Небесная механика. Фундаментальная астрономия. Теория динамической и позиционной астрономии
UDK 523 Солнечная система
UDK 524 Звезды и звездные системы. Вселенная Солнце и Солнечная система
UDK 52-1 Метод изучения
UDK 52-6 Излучение и связанные с ним процессы
GRNTI 41.00 АСТРОНОМИЯ
GRNTI 29.35 Радиофизика. Физические основы электроники
GRNTI 29.31 Оптика
GRNTI 29.33 Лазерная физика
GRNTI 29.27 Физика плазмы
GRNTI 29.05 Физика элементарных частиц. Теория полей. Физика высоких энергий
OKSO 03.06.01 Физика и астрономия
OKSO 03.05.01 Астрономия
OKSO 03.04.03 Радиофизика
BBK 2 ЕСТЕСТВЕННЫЕ НАУКИ
BBK 223 Физика
TBK 614 Астрономия
TBK 6135 Оптика
BISAC SCI004000 Astronomy
BISAC SCI005000 Physics / Astrophysics
Language:
English
Keywords:
stars: protoplanetary disks, magnetic fields, pre-main sequence
Abstract (English):
We study the fossil large-scale magnetic field evolution in a turbulent accretion disk of young T Tauri star. The coefficient of turbulent viscosity is calculated according to the Shakura and Sunyaev model. The modeling is performed taking into account the weakening of the turbulence in the region of low ionization fraction ("dead" zone). The ionization structure is calculated taking into account thermal ionization, cosmic rays and radioactive elements, radiative recombinations and recombinations on dust grains. The magnetic field is calculated taking into account ambipolar diffusion. The simulations show that the magnetic field is frozen in gas and its strength is proportional to the gas surface density in the inner region of the disk, $R<0.2$ AU. The magnetic field strength increases from $10^2$ G to $10^3$ G in this region within 5 Myr. The outer boundary of the "dead" zone depends on the dust grain size and ranges from 30 AU for $a_g=0.1$ $\mu$m to 3 AU for $a_g=10^3$ $\mu$m. The size of the "dead" zone decreases with time. The magnetic field strength inside the "dead" zone remains practically constant at around $10^{-3}$–$10^{-4}$ G during the disk evolution.
We study the fossil large-scale magnetic field evolution in a turbulent accretion disk of young T Tauri star. The coefficient of turbulent viscosity is calculated according to the Shakura and Sunyaev model. The modeling is performed taking into account the weakening of the turbulence in the region of low ionization fraction ("dead" zone). The ionization structure is calculated taking into account thermal ionization, cosmic rays and radioactive elements, radiative recombinations and recombinations on dust grains. The magnetic field is calculated taking into account ambipolar diffusion. The simulations show that the magnetic field is frozen in gas and its strength is proportional to the gas surface density in the inner region of the disk, $R<0.2$ AU. The magnetic field strength increases from $10^2$ G to $10^3$ G in this region within 5 Myr. The outer boundary of the "dead" zone depends on the dust grain size and ranges from 30 AU for $a_g=0.1$ $\mu$m to 3 AU for $a_g=10^3$ $\mu$m. The size of the "dead" zone decreases with time. The magnetic field strength inside the "dead" zone remains practically constant at around $10^{-3}$–$10^{-4}$ G during the disk evolution.
Keywords:
stars: protoplanetary disks, magnetic fields, pre-main sequence
stars: protoplanetary disks, magnetic fields, pre-main sequence
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