On the Existence of Shear-current Effects in Magnetized Burgulence

↓ Direkt till sidans innehåll
↓ Direkt till sidans sekundära innehåll (sidomenyn)

Search: onr:"swepub:oai:DiVA.org:kth-289294" > On the Existence of...

1 of 1
Previous record
Next record
To hitlist

Details
MARC

Käpylä, Maarit J.Stockholms universitet,Nordiska institutet för teoretisk fysik (Nordita),Aalto University, Finland; Max Planck Institute for Solar System Research, Germany,Aalto Univ, Dept Comp Sci, POB 15400, FI-00076 Aalto, Finland.;Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany.; Nordita SU (author)

On the Existence of Shear-current Effects in Magnetized Burgulence

Article/chapterEnglish2020

Publisher, publication year, extent ...

2020-12-28
American Astronomical Society,2020
printrdacarrier

Numbers

LIBRIS-ID:oai:DiVA.org:kth-289294
https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289294URI
https://doi.org/10.3847/1538-4357/abc1e8DOI
https://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-190696URI

Supplementary language notes

Language:English
Summary in:English

Part of subdatabase

SwePubSwePub

Classification

Subject category:ref swepub-contenttype
Subject category:art swepub-publicationtype

Notes

QC 20210126
The possibility of explaining shear flow dynamos by a magnetic shear-current (MSC) effect is examined via numerical simulations. Our primary diagnostics is the determination of the turbulent magnetic diffusivity tensor eta. In our setup, a negative sign of its component eta(yx) is necessary for coherent dynamo action by the SC effect. To be able to measure turbulent transport coefficients from systems with magnetic background turbulence, we present an extension of the test-field method (TFM) applicable to our setup where the pressure gradient is dropped from the momentum equation: the nonlinear TFM (NLTFM). Our momentum equation is related to Burgers' equation and the resulting flows are referred to as magnetized burgulence. We use both stochastic kinetic and magnetic forcings to mimic cases without and with simultaneous small-scale dynamo action. When we force only kinetically, negative eta(yx) are obtained with exponential growth in both the radial and azimuthal mean magnetic field components. Using magnetokinetic forcing, the field growth is no longer exponential, while NLTFM yields positive eta(yx). By employing an alternative forcing from which wavevectors whose components correspond to the largest scales are removed, the exponential growth is recovered, but the NLTFM results do not change significantly. Analyzing the dynamo excitation conditions for the coherent SC and incoherent alpha and SC effects shows that the incoherent effects are the main drivers of the dynamo in the majority of cases. We find no evidence for MSC-effect-driven dynamos in our simulations.

Subject headings and genre

NATURVETENSKAP Fysik hsv//swe
NATURAL SCIENCES Physical Sciences hsv//eng
Magnetohydrodynamical simulations
Astrophysical magnetism

Added entries (persons, corporate bodies, meetings, titles ...)

Vizoso, Javier AlvarezMax Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany. (author)
Rheinhardt, MatthiasAalto Univ, Dept Comp Sci, POB 15400, FI-00076 Aalto, Finland. (author)
Brandenburg, AxelStockholms universitet,KTH,Nordic Institute for Theoretical Physics NORDITA,Stockholm Univ, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden.;Stockholm Univ, AlbaNova Univ Ctr, Dept Astron, SE-10691 Stockholm, Sweden.;Carnegie Mellon Univ, McWilliams Ctr Cosmol, Pittsburgh, PA 15213 USA.;Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA.,Nordiska institutet för teoretisk fysik (Nordita),Institutionen för astronomi,Carnegie Mellon University, USA(Swepub:su)brandenb (author)
Singh, Nishant K.Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany.;Interuniv Ctr Astron & Astrophys, Post Bag 4, Pune 411007, Maharashtra, India. (author)
Stockholms universitetNordiska institutet för teoretisk fysik (Nordita) (creator_code:org_t)

Related titles

In:Astrophysical Journal: American Astronomical Society905:20004-637X1538-4357

Internet link

Find in a library

Astrophysical Journal (Search for host publication in LIBRIS)

To the university's database

1 of 1
Previous record
Next record
To hitlist

Find more in SwePub

By the author/editor: Käpylä, Maarit J ...; Vizoso, Javier A ...; Rheinhardt, Matt ...; Brandenburg, Axe ...; Singh, Nishant K ...

About the subject

NATURAL SCIENCES: NATURAL SCIENCES; and Physical Science ...

Articles in the publication: Astrophysical Jo ...

By the university: Royal Institute of Technology; Stockholm University

Search outside SwePub

Extend your search to:: Google; Google Book Search; Google Scholar

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

LIBRIS.kb.se