J 2023

Accretion disc backflow in resistive MHD simulations

MISHRA, R., Miljenko ČEMELJIĆ a Wlodzimierz KLUŹNIAK

Základní údaje

Originální název

Accretion disc backflow in resistive MHD simulations

Autoři

MISHRA, R., Miljenko ČEMELJIĆ (191 Chorvatsko, domácí) a Wlodzimierz KLUŹNIAK (616 Polsko)

Vydání

Monthly Notices of the Royal Astronomical Society, 2023, 0035-8711

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Odkazy

URL

Kód RIV

RIV/47813059:19630/23:A0000262

Organizační jednotka

Fyzikální ústav v Opavě

DOI

http://dx.doi.org/10.1093/mnras/stad1691

UT WoS

001019516400005

Klíčová slova anglicky

accretion; accretion discs;magnetic fields;(magnetohydrodynamics) MHD;methods: numerical

Štítky

RIV24, UF

Příznaky

Mezinárodní význam, Recenzováno

Návaznosti

GX21-06825X, projekt VaV.
Změněno: 14. 2. 2024 11:18, Mgr. Pavlína Jalůvková

Anotace

V originále

We investigate accretion onto a central star, with the size, rotation rate, and magnetic dipole of a young stellar object, to study the flow pattern (velocity and density) of the fluid within and outside of the disc. We perform resistive magnetohydrodynamic (MHD) simulations of thin discs, varying the parameters such as the stellar rotation rate and (anomalous) coefficients of viscosity and resistivity in the disc. To provide a benchmark for the results and to compare them with known analytic results, we also perform purely hydrodynamic (HD) simulations for the same problem. Although obtained for different situations with differing inner boundary condition, the disc structure in the HD simulations closely follows the analytic solution of Kluzniak and Kita - in particular, a region of 'mid-plane' backflow exists in the right range of radii, depending on the viscosity parameter. In the MHD solutions, whenever the magnetic Prandtl number does not exceed a certain critical value, the mid-plane backflow exists throughout the accretion disc, extending all the way down to the foot point of the accretion funnel flow where the disc transitions to a magnetic funnel flow. For values of the magnetic Prandtl number close to the critical value the backflow and the inner disc undergo a quasi-periodic radial oscillation, otherwise the backflow is steady, as is the disc solution. From our results, supplemented by our reading of the literature, we suggest that mid-plane backflow is a real, physical, and not only numerical feature of at least some accretion discs.
Zobrazeno: 28. 12. 2024 21:31