18 citations · 56 across the 16 of their papers we have counts for
16 papers
Magnetic Dynamo Driven by Inertial Waves
A. Mishra, G. Mamatsashvili, M. Le Bars +2
We demonstrate, by studying precession-driven flows, that inertial wave hydrodynamic turbulence can drive a robust magnetic dynamo action. Motivated by the stronger damping of larg…
Tidal triggers and the predictability of solar activity
F. Stefani, G. M. Horstmann, G. Mamatsashvili +1
Magneto-Rossby waves in the solar tachocline are currently considered to be one of the main determinants of solar activity. In particular, they can give rise to the quasi-biennial…
Strong and weak dynamo regimes in Taylor-Couette flows
A. Mishra, G. Mamatsashvili, F. Stefani
We reveal a nonlinear magnetic dynamo in a Taylor-Couette flow at small magnetic Prandtl numbers , which has been previously believed to exist only at higher $Pm\gtrsim 1…
One-winged butterflies: mode selection for azimuthal magnetorotational instability by thermal convection
A. Mishra, G. Mamatsashvili, M. Seilmayer +1
The effects of thermal convection on turbulence in accretion discs, and particularly its interplay with the magnetorotational instability (MRI), are of significant astrophysical in…
Dynamo action driven by precessional turbulence
V. Kumar, F. Pizzi, G. Mamatsashvili +3
We reveal and analyze an efficient magnetic dynamo action due to precession-driven hydrodynamic turbulence in the local model of a precessional flow, focusing on the kinematic stag…
Non-axisymmetric modes of magnetorotational and possible hydrodynamical instabilities in the upcoming DRESDYN-MRI experiments -- linear and nonlinear dynamics
A. Mishra, G. Mamatsashvili, F. Stefani
The quest for an unambiguous detection of magnetorotational instability (MRI) in experiments is still ongoing despite recent promising results. To conclusively identify MRI in the…
Nonlinear evolution of magnetorotational instability in a magnetized Taylor-Couette flow: scaling properties and relation to upcoming DRESDYN-MRI experiment
A. Mishra, G. Mamatsashvili, F. Stefani
Magnetorotational instability (MRI) is the most likely mechanism driving angular momentum transport in astrophysical disks. However, despite many efforts, a conclusive experimental…
Weak branch and multimodal convection in rapidly rotating spheres at low Prandtl number
Ferran Garcia, Frank Stefani, Emmanuel Dormy
The focus of this study is to investigate primary and secondary bifurcations to weakly nonlinear flows (weak branch) in convective rotating spheres in a regime where only strongly…
From helical to standard magnetorotational instability: predictions for upcoming liquid sodium experiments
A. Mishra, G. Mamatsashvili, F. Stefani
We conduct a linear analysis of axisymmetric magnetorotational instability (MRI) in a magnetized cylindrical Taylor-Couette (TC) flow for its standard version (SMRI) with a purely…
Modulated rotating waves and triadic resonances in spherical fluid systems: The case of magnetized spherical Couette flow
Ferran Garcia, André Giesecke, Frank Stefani
The existence of triadic resonances in the magnetized spherical Couette system (MSC) is related to the development of modulated rotating waves, which are quasiperiodic flows unders…
Schwabe, Gleissberg, Suess-de Vries: Towards a consistent model of planetary synchronization of solar cycles
F. Stefani, A. Giesecke, M. Seilmayer +2
Aiming at a consistent planetary synchronization model of both short-term and long-term solar cycles, we start with an analysis of Schove's historical data of cycle maxima. Their d…
The Tayler instability at low magnetic Prandtl numbers: Chiral symmetry breaking and synchronizable helicity oscillations
F. Stefani, V. Galindo, A. Giesecke +2
The current-driven, kink-type Tayler instability (TI) is a key ingredient of the Tayler-Spruit dynamo model for the generation of stellar magnetic fields, but is also discussed as…
Linking dissipation-induced instabilities with nonmodal growth: the case of helical magnetorotational instability
George Mamatsashvili, Frank Stefani
The helical magnetorotational instability is known to work for resistive rotational flows with comparably steep negative or extremely steep positive shear. The corresponding lower…
Subcritical excitation of the current-driven Tayler instability by super-rotation
G. Rüdiger, M. Schultz, M. Gellert +1
It is known that in a hydrodynamic Taylor-Couette system uniform rotation or a rotation law with positive shear ('super-rotation') are linearly stable. It is also known that a cond…
Numerical simulations for the DRESDYN precession dynamo
A. Giesecke, T. Albrecht, G. Gerbeth +2
The next generation dynamo experiment currently under development at Helmholtz-Zentrum Dresden-Rossendorf (HZDR) will consist of a precessing cylindrical container filled with liqu…
Spectral properties of oscillatory and non-oscillatory α^2-dynamos
A. Giesecke, F. Stefani, G. Gerbeth
The eigenvalues and eigenfunctions of a linear α^{2}-dynamo have been computed for different spatial distributions of an isotropic α-effect. Oscillatory solutions are obtained when…