Selected research

A selection of papers on forced flows, dynamos and core–mantle coupling. For the full list, see journal publications.

Could lunar tides sustain the early Earth’s dynamo ? (2026)
Vidal & Cébron, Comptes Rendus Géoscience 358, 1–26. Lunar tides may once have been strong enough to excite turbulence in Earth’s core. However, extrapolating the resulting dynamo scalings suggests that tidal forcing alone was insufficient to explain the ancient geomagnetic field. This places quantitative constraints on the possible mechanisms that powered Earth’s earliest dynamo.

Semiconvection and planetary dynamos (2025-2026)
Pružina, Cébron and Schaeffer, Astronomy & Astrophysics 703, A135. In rotating stratified shells, double-diffusive motions can reorganise the interior into convecting and stable layers. The resulting dynamo and the zonal flows in the overlying stable layer offer a possible explanation for the simple external magnetic fields of giant planets, particularly Saturn.

Topographic drag in rapidly rotating fluids (2026)
Giraud, Noir, Cébron, Vidal and Monville, Journal of Fluid Mechanics 1040, A14. Vadim Giraud and colleagues examined flow over finite-slope topography. Inertial waves carry energy away from the boundary and contribute to the drag, adding a mechanism for dissipation and torque in rapidly rotating fluid layers.

Damping of inner-core translation (2026)
Personnettaz, Cébron, Schaeffer, Deguen and Mandea, Earth and Planetary Science Letters 690, 120156. Paolo Personnettaz and colleagues studied how viscosity and electrical currents damp translational oscillations of Earth’s inner core. Their data and code accompany the paper ; the predicted damping matters for attempts to detect these modes.

Magnetohydrodynamic drag and inner-core oscillations (2026)
Cébron & Personnettaz, Journal of Fluid Mechanics 1045, A13
We developed a theory of the forces acting on an oscillating sphere inside a confined, rotating, electrically conducting fluid. Combining analytical calculations and numerical simulations, the study brings viscous, rotational and magnetic effects into a common framework, with applications to planetary inner-core oscillations and laboratory experiments.

Topographic drag at the core–mantle interface (2025)
Monville, Cébron and Jault, Journal of Geophysical Research : Solid Earth 130, e2024JB029770. Rémy Monville led this local study of fluid flow past boundary topography. Pressure, viscous and electromagnetic stresses all contribute to the drag and hence to the torque exchanged between core and mantle.

Mean zonal flows from mechanical forcing (2021)
Cébron, Vidal, Schaeffer, Borderies and Sauret, Journal of Fluid Mechanics 916, A39. Weak precession, libration or tides can nevertheless generate a persistent zonal flow in a rotating spheroid. The paper works out the role of nonlinear boundary layers in setting up this mean circulation.

Precession and the lunar core (2019)
Cébron et al., Geophysical Journal International 219, S34–S57. We calculated flows and dissipation in precessing spherical shells, then applied the results to the Moon. Comparing the model with lunar conditions puts the precessional dynamo idea to a quantitative test.

Elliptical instability in terrestrial planets and moons (2012)
Cébron, Le Bars, Moutou and Le Gal, Astronomy & Astrophysics 539, A78. Tides and libration deform planetary fluid layers and can excite elliptical instability. We examined when this mechanism could operate in terrestrial planets and moons, and what it might mean for their internal flows and dissipation.