Finite amplitude Alfvén-cyclotron waves are believed to play an important role in coronal heating and nonthermal properties of velocity distribution functions. These effects are thought to be due to parametrically unstable Alfvén-cyclotron waves and electrostatic bursts of ion-acoustic like waves. It is shown here that large amplitude Alfvéncyclotron waves propagating in multi-ion plasmas with ...

The possibility of velocity shear-induced linear transformations of different magnetohydrodynamic waves in the solar wind is studied both analytically and numerically. A quantitative analysis of the wave transformation processes for all possible plasma-β regimes is performed. By applying the obtained criteria for effective wave coupling to the solar wind parameters, we show that velocity sheari...

A new technique for manipulation and control of gradient-driven instabilities through nonlinear interaction with Alfvén waves in a laboratory plasma is presented. A narrow, field-aligned density depletion is created in the Large Plasma Device, resulting in coherent, unstable fluctuations on the periphery of the depletion. Two independent shear Alfvén waves are launched along the depletion at se...

We present a series of models for the plasma properties along open magnetic flux tubes rooted in solar coronal holes, streamers, and active regions. These models represent the first self-consistent solutions that combine: (1) chromospheric heating driven by an empirically guided acoustic wave spectrum, (2) coronal heating from Alfvén waves that have been partially reflected, then damped by anis...

Shear Alfvén waves with transverse scales of electron skin-depth size are launched with a dual-disk antenna in the Large Plasma Device at UCLA. The waves are studied in the kinetic and inertial regimes. The kinetic shear Alfvén wave is observed for the first time and exhibits predicted radial structure. The perpendicular propagation of the wave is also studied for the first time, and it is foun...

The treatment of kinetic shear Alfvén waves in homogeneous magnetized plasmas by means of Vlasov simulation is examined. To this end, the driftkinetic version of the Vlasov–Maxwell equations is solved via various numerical schemes, all employing a grid in (1 + 1)D phase space. Since kinetic shear Alfvén waves are Landau damped, the use of an equidistant grid in velocity space leads to a recurre...

The efficacy of fast/slow MHD mode conversion in the surface layers of sunspots has been demonstrated over recent years using a number of modelling techniques, including ray theory, perturbation theory, differential eigensystem analysis, and direct numerical simulation. These show that significant energy may be transferred between the fast and slow modes in the neighbourhood of the equipartitio...

The present paper studies the heating of coronal loops by linear resonant Alfvén waves that are excited by the motions of the photospheric footpoints of the magnetic field lines. The analysis is restricted to torsionally polarised footpoint motions in an axially symmetric system so that only torsional Alfvénwaves are excited. For this subclass of footpointmotions, the Alfvén and cusp singularit...

The flow of energy through the solar atmosphere and the heating of the Sun's outer regions are still not understood. Here, we report the detection of oscillatory phenomena associated with a large bright-point group that is 430,000 square kilometers in area and located near the solar disk center. Wavelet analysis reveals full-width half-maximum oscillations with periodicities ranging from 126 to...

We characterize low-frequency plasma waves in the Martian magnetosphere and in the upstream region by using transport ratios. To compute the transport ratios, we use Mars Atmosphere and Volatile EvolutioN mission’s (MAVEN) solar wind ion analyzer and suprathermal and thermal ion composition instrument measurements of the ion moments and the magnetometer measurements of the magnetic field. We fi...