Generation of large-scale magnetic fields by small-scale dynamo in shear flows

Squire, J.; Bhattacharjee, A.

doi:10.1103/PhysRevLett.115.175003

Title: Generation of large-scale magnetic fields by small-scale dynamo in shear flows

Journal Article · Tue Oct 20 00:00:00 EDT 2015 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.115.175003· OSTI ID:1259593

Squire, J. ^[1]; Bhattacharjee, A. ^[2]

Princeton Univ., NJ (United States). Dept. of Astrophysical Sciences; Max Planck & Princeton Ctr Plasma Phys, Princeton, NJ 08543 USA; Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States)
Princeton Univ., NJ (United States). Dept. of Astrophysical Sciences; Max Planck & Princeton Ctr Plasma Phys, Princeton, NJ 08543 USA; Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

We propose a new mechanism for a turbulent mean-field dynamo in which the magnetic fluctuations resulting from a small-scale dynamo drive the generation of large-scale magnetic fields. This is in stark contrast to the common idea that small-scale magnetic fields should be harmful to large-scale dynamo action. These dynamos occur in the presence of a large-scale velocity shear and do not require net helicity, resulting from off-diagonal components of the turbulent resistivity tensor as the magnetic analogue of the "shear-current" effect. Furthermore, given the inevitable existence of nonhelical small-scale magnetic fields in turbulent plasmas, as well as the generic nature of velocity shear, the suggested mechanism may help explain the generation of large-scale magnetic fields across a wide range of astrophysical objects.

View Accepted Manuscript (DOE)

View Accepted Manuscript (Publisher)

Cite

Export

Save

Research Organization:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC02-09CH11466; AC02-09-CH11466

OSTI ID:: 1259593

Alternate ID(s):: OSTI ID: 1224124

Report Number(s):: PPPL-5148; PRLTAO

Journal Information:: Physical Review Letters, Vol. 115, Issue 17; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

Citation Metrics:

Cited by: 27 works

Citation information provided by
Web of Science

References (27)

The Solar Cycle Hathaway, David H. Living Reviews in Solar Physics, Vol. 7, Issue 1 https://doi.org/10.12942/lrsp-2010-1	journal	March 2010
Astrophysical magnetic fields and nonlinear dynamo theory Brandenburg, Axel; Subramanian, Kandaswamy Physics Reports, Vol. 417, Issue 1-4 https://doi.org/10.1016/j.physrep.2005.06.005	journal	October 2005
Cross helicity and related dynamo Yokoi, N. Geophysical & Astrophysical Fluid Dynamics, Vol. 107, Issue 1-2 https://doi.org/10.1080/03091929.2012.754022	journal	June 2012
The spectrum of random magnetic fields in the mean field dynamo theory of the Galactic magnetic field Kulsrud, Russell M.; Anderson, Stephen W. The Astrophysical Journal, Vol. 396 https://doi.org/10.1086/171743	journal	September 1992
Problems with kinematic mean field electrodynamics at high magnetic Reynolds numbers Cattaneo, F.; Hughes, D. W. Monthly Notices of the Royal Astronomical Society: Letters, Vol. 395, Issue 1 https://doi.org/10.1111/j.1745-3933.2009.00639.x	journal	May 2009
Fluctuation dynamo and turbulent induction at low magnetic Prandtl numbers Schekochihin, A. A.; Iskakov, A. B.; Cowley, S. C. New Journal of Physics, Vol. 9, Issue 8 https://doi.org/10.1088/1367-2630/9/8/300	journal	August 2007
Magnetic-Field Generation in Helical Turbulence Boldyrev, Stanislav; Cattaneo, Fausto; Rosner, Robert Physical Review Letters, Vol. 95, Issue 25 https://doi.org/10.1103/PhysRevLett.95.255001	journal	December 2005
Self-consistent theory of mean-field electrodynamics Gruzinov, A. V.; Diamond, P. H. Physical Review Letters, Vol. 72, Issue 11 https://doi.org/10.1103/PhysRevLett.72.1651	journal	March 1994
Self-Consistency Constraints on the Dynamo Mechanism Bhattacharjee, A.; Yuan, Y. The Astrophysical Journal, Vol. 449 https://doi.org/10.1086/176094	journal	August 1995
New Dynamical Mean-Field Dynamo Theory and Closure Approach Blackman, Eric G.; Field, George B. Physical Review Letters, Vol. 89, Issue 26 https://doi.org/10.1103/PhysRevLett.89.265007	journal	December 2002
Efficient Small-Scale Dynamo in the Solar Convection zone Hotta, H.; Rempel, M.; Yokoyama, T. The Astrophysical Journal, Vol. 803, Issue 1 https://doi.org/10.1088/0004-637X/803/1/42	journal	April 2015
Statistical Simulation of the Magnetorotational Dynamo Squire, J.; Bhattacharjee, A. Physical Review Letters, Vol. 114, Issue 8 https://doi.org/10.1103/PhysRevLett.114.085002	journal	February 2015
Nonlinear theory of a “shear-current” effect and mean-field magnetic dynamos Rogachevskii, Igor; Kleeorin, Nathan Physical Review E, Vol. 70, Issue 4 https://doi.org/10.1103/PhysRevE.70.046310	journal	October 2004
Numerical experiments on dynamo action in sheared and rotating turbulence Yousef, T. A.; Heinemann, T.; Rincon, F. Astronomische Nachrichten, Vol. 329, Issue 7 https://doi.org/10.1002/asna.200811018	journal	September 2008
Magnetic Diffusivity Tensor and Dynamo Effects in Rotating and Shearing Turbulence Brandenburg, A.; Rädler, K. ‐H.; Rheinhardt, M. The Astrophysical Journal, Vol. 676, Issue 1 https://doi.org/10.1086/527373	journal	March 2008
Mean electromotive force in turbulent shear flow Urpin, V. Physical Review E, Vol. 65, Issue 2 https://doi.org/10.1103/PhysRevE.65.026301	journal	January 2002
Electromotive force and large-scale magnetic dynamo in a turbulent flow with a mean shear Rogachevskii, Igor; Kleeorin, Nathan Physical Review E, Vol. 68, Issue 3 https://doi.org/10.1103/PhysRevE.68.036301	journal	September 2003
Mean electromotive force due to turbulence of a conducting fluid in the presence of mean flow Rädler, Karl-Heinz; Stepanov, Rodion Physical Review E, Vol. 73, Issue 5 https://doi.org/10.1103/PhysRevE.73.056311	journal	May 2006
Transport coefficients for the shear dynamo problem at small Reynolds numbers Singh, Nishant K.; Sridhar, S. Physical Review E, Vol. 83, Issue 5 https://doi.org/10.1103/PhysRevE.83.056309	journal	May 2011
Dynamics of streamwise rolls and streaks in turbulent wall-bounded shear flow Farrell, Brian F.; Ioannou, Petros J. Journal of Fluid Mechanics, Vol. 708 https://doi.org/10.1017/jfm.2012.300	journal	August 2012
Astrophysical Fluid Dynamics via Direct Statistical Simulation Tobias, S. M.; Dagon, K.; Marston, J. B. The Astrophysical Journal, Vol. 727, Issue 2 https://doi.org/10.1088/0004-637X/727/2/127	journal	January 2011
Impact of dimensionless numbers on the efficiency of magnetorotational instability induced turbulent transport Lesur, G.; Longaretti, P. -Y. Monthly Notices of the Royal Astronomical Society, Vol. 378, Issue 4 https://doi.org/10.1111/j.1365-2966.2007.11888.x	journal	June 2007
On self-sustained dynamo cycles in accretion discs Lesur, G.; Ogilvie, G. I. Astronomy & Astrophysics, Vol. 488, Issue 2 https://doi.org/10.1051/0004-6361:200810152	journal	July 2008
Test-field method for mean-field coefficients with MHD background Rheinhardt, M.; Brandenburg, A. Astronomy and Astrophysics, Vol. 520 https://doi.org/10.1051/0004-6361/201014700	journal	September 2010
Local and Nonlocal Magnetic Diffusion and Alpha-Effect Tensors in Shear Flow Turbulence Brandenburg, Axel; Sokoloff, Dmitry Geophysical & Astrophysical Fluid Dynamics, Vol. 96, Issue 4 https://doi.org/10.1080/03091920290032974	journal	January 2002
Generation of Magnetic Field by Combined Action of Turbulence and Shear Yousef, T. A.; Heinemann, T.; Schekochihin, A. A. Physical Review Letters, Vol. 100, Issue 18 https://doi.org/10.1103/PhysRevLett.100.184501	journal	May 2008
Shear-driven dynamo waves at high magnetic Reynolds number Tobias, S. M.; Cattaneo, F. Nature, Vol. 497, Issue 7450 https://doi.org/10.1038/nature12177	journal	May 2013

Cited By (3)

Solar Magnetoconvection and Small-Scale Dynamo: Recent Developments in Observation and Simulation Borrero, J. M.; Jafarzadeh, S.; Schüssler, M. Space Science Reviews, Vol. 210, Issue 1-4 https://doi.org/10.1007/s11214-015-0204-5	journal	December 2015
Non-linear galactic dynamos and the magnetic Rädler effect Chamandy, Luke; Singh, Nishant K. Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 1 https://doi.org/10.1093/mnras/sty2301	journal	August 2018
Solar Magnetoconvection and Small-Scale Dynamo Borrero, J. M.; Jafarzadeh, S.; Schüssler, M. https://doi.org/10.1007/978-94-024-1521-6_10	book

Similar Records

The magnetic shear-current effect: Generation of large-scale magnetic fields by the small-scale dynamo

Journal Article · Mon Mar 14 00:00:00 EDT 2016 · Journal of Plasma Physics · OSTI ID:1259593

Squire, J.; Bhattacharjee, A.

Shear dynamo, turbulence, and the magnetorotational instability

Thesis/Dissertation · Tue Sep 01 00:00:00 EDT 2015 · OSTI ID:1259593

Squire, Jonathan

Coherent nonhelical shear dynamos driven by magnetic fluctuations at low Reynolds numbers

Journal Article · Wed Oct 28 00:00:00 EDT 2015 · The Astrophysical Journal (Online) · OSTI ID:1259593

Squire, J.; Bhattacharjee, A.

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Title: Generation of large-scale magnetic fields by small-scale dynamo in shear flows

Citation Formats

References (27)

Cited By (3)

Similar Records

Related Subjects