Alfvén Waves in the Solar Corona

Abstract

Alfvén waves, transverse incompressible magnetic oscillations, have been proposed as a possible mechanism to heat the Sun's corona to millions of degrees by transporting convective energy from the photosphere into the diffuse corona. We report the detection of Alfvén waves in intensity, line-of-sight velocity, and linear polarization images of the solar corona taken using the FeXIII 1074.7-nanometer coronal emission line with the Coronal Multi-Channel Polarimeter (CoMP) instrument at the National Solar Observatory, New Mexico. Ubiquitous upward propagating waves were seen, with phase speeds of 1 to 4 megameters per second and trajectories consistent with the direction of the magnetic field inferred from the linear polarization measurements. An estimate of the energy carried by the waves that we spatially resolved indicates that they are too weak to heat the solar corona; however, unresolved Alfvén waves may carry sufficient energy.

Resonant Alfvén waves in partially ionized plasmas of the solar atmosphere

“…This effectively imposes a lower limit for the period of kink waves observable in the corona. This is consistent with the observed periods of coronal waves (e.g., Tomczyk et al 2007;Tomczyk & McIntosh 2009;McIntosh et al 2011). …”

“…Therefore, it was predicted that high-frequency kink waves become damped in length scales shorter than low-frequency waves. Verth et al (2010) showed that this result is consistent with the CoMP observations of damped coronal waves (Tomczyk et al 2007;Tomczyk & McIntosh 2009). Subsequent investigations have extended the original work by TGV by incorporating effects not considered in their paper.…”

“…For example, Alfvénic transverse waves propagating in magnetic waveguides of the solar corona were first observed by Tomczyk et al (2007) and Tomczyk & McIntosh (2009) using the Coronal Multichannel Polarimeter (CoMP), and more recently by McIntosh et al (2011) using SDO/AIA. In chromospheric spicules, the presence of Doppler oscillations is known for more than 40 years (see the review by Zaqarashvili & Erdélyi 2009).…”

Solar Wind Electrons Alphas and Protons (SWEAP) Investigation: Design of the Solar Wind and Coronal Plasma Instrument Suite for Solar Probe Plus

“…Ion cyclotron heating and the turbulent cascade models exploit the notion that low frequency shear Alfven waves excited in the chromosphere will survive into the lower corona. Upward propagating Alfven modes have been observed in the chromosphere (de Pontieu et al 2007), in the lower corona by Hinode (Ofman and Wang 2007;Okamoto et al 2007) and by ground-based detectors (Tomczyk et al 2007). The ion cyclotron heating mechanism proceeds by resonant wave particle interactions with Alfven waves, leading to heating of the solar corona (Isenberg 2001b(Isenberg , 2004.…”

Coronal waves in coronal loops during non-flare stage

“…Special program of TRACE observation made possible by De Groof et al (2004) to detect and investigate propagating disturbances in loop. Tomczyk et al (2007) reported about very interesting observation of oscillation of velocities field in quiet system of loop using Coronal Multichannel Polarimeter.…”