HEATING OF THE SOLAR CHROMOSPHERE AND CORONA BY ALFVÉN WAVE TURBULENCE

By A. A. Ballegooijen, Mahboubeh Asgari-Targhi, S. Cranmer, E. DeLuca. 2011

297 citations recorded by the source corpus.

A three-dimensional magnetohydrodynamic (MHD) model for the propagation and dissipation of Alfvén waves in a coronal loop is developed. The model includes the lower atmospheres at the two ends of the loop. The waves originate on small spatial scales (less than 100 km) inside the kilogauss flux elements in the photosphere. The model describes the nonlinear interactions between Alfvén waves using the reduced MHD approximation. The increase of Alfvén speed with height in the chromosphere and transition region (TR) causes strong wave reflection, which leads to counter-propagating waves and turbulence in the photospheric and chromospheric parts of the flux tube. Part of the wave energy is transmitted through the TR and produces turbulence in the corona. We find that the hot coronal loops typically found in active regions can be explained in terms of Alfvén wave turbulence, provided that the small-scale footpoint motions have velocities of 1–2 km s−1 and timescales of 60–200 s. The heating rate per unit volume in the chromosphere is two to three orders of magnitude larger than that in the corona. We construct a series of models with different values of the model parameters, and find that the coronal heating rate increases with coronal field strength and decreases with loop length. We conclude that coronal loops and the underlying chromosphere may both be heated by Alfvénic turbulence.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/72e85ac8051462d00b649de3f9b9f8441e2ed95b

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. J. Leenaarts
2. M. Carlsson
3. Bart De Pontieu
4. S. Cranmer
5. V. Hansteen
6. J. Laming
7. R. Erdélyi
8. B. Gudiksen

Citations in the corpus

• Origins of the Ambient Solar Wind: Implications for Space Weather (2017, background): “…extended corona (Coleman 1968; Hollweg 1986; Velli et al. 1991; Matthaeus et al. 1999; Suzuki and Inutsuka 2006; Cranmer et al. 2007; Ofman 2010; van Ballegooijen et al. 2011; Chandran et al. 2011; Matsumoto and Suzuki 2012; Perez and Chandran 2013; Lionello et al. 2014; Tenerani and Velli 2017;…”
• Multiwavelength Studies of MHD Waves in the Solar Chromosphere (2015, background): “…resonant absorption and phase mixing (e.g., Goossens and De Groof 2001; Ruderman and Roberts 2002; Goossens et al. 2002), turbulent mixing (van Ballegooijen et al. 2011), in addition to examples of mode conversion (e.g., Ulmschneider et al. 1991; Kalkofen 1997) and thermal conduction (Ofman…”
• INCORPORATING KINETIC PHYSICS INTO A TWO-FLUID SOLAR-WIND MODEL WITH TEMPERATURE ANISOTROPY AND LOW-FREQUENCY ALFVÉN-WAVE TURBULENCE (2011, background): “Interactions betweenz+ and z− fluctuations then cause wave energy to cascade from large scales to small scales (Iroshnikov 1963; Kraichnan 1965; Velli et al. 1989; Matthaeus et al. 1999; van Ballegooijen et al. 2011).”
• Alfvén Waves in the Solar Atmosphere (2012, background): “…Ofman & Davila 1995; Erdélyi and Goossens 1995; Ruderman and Roberts 2002; Goossens et al. 2011), phase mixing (Heyvaerts & Priest 1983; Ofman & Aschwanden 2002), Alfvén turbulence (Cranmer & van Ballegooigen 2005; van Ballegooijen et al. 2011) and/or mode conversion (Suzuki & Inutsuka 2005).”
• The FIP and Inverse FIP Effects in Solar and Stellar Coronae (2015, background): “Van Ballegooijen et al. (2011) challenge some of these ideas and offer a more traditional view of an Alfvén wave heated corona, where Alfvén waves are introduced at loop footpoints from below and are either transmitted or reflected, following Hollweg (1984).”
• TESTING A PREDICTIVE THEORETICAL MODEL FOR THE MASS LOSS RATES OF COOL STARS (2011, background): “…coronal heating and solar wind acceleration have begun to succeed in reproducing a wide range of observations without the need for ad hoc free parameters (e.g., Suzuki 2006; Cranmer et al. 2007; Rappazzo et al. 2008; Verdini et al. 2010; Bingert & Peter 2011; van Ballegooijen et al. 2011).”
• A publicly available simulation of an enhanced network region of the Sun (2015, background): “…of this non-thermal broadening in the outer atmosphere is still unclear, but the presence of strong shocks (Carlsson & Stein 1992, 1997; De Pontieu et al. 2015), torsional motions (De Pontieu et al. 2014a), and Alfvén wave turbulence (van Ballegooijen et al. 2011) are some of the candidates.”
• A SYSTEMATIC SURVEY OF HIGH-TEMPERATURE EMISSION IN SOLAR ACTIVE REGIONS (2012, methodology): “…in behavior between loops at different temperatures appears puzzling, but may be explained by recent work on wave models of coronal heating. van Ballegooijen et al. (2011) and Asgari-Targhi & van Ballegooijen (2012) have studied the dissipation of Alfvén waves in the chromosphere and corona.”