Thumbnail
Access Restriction
Open

Author Mac Cormack, Cecilia ♦ Vásquez, Alberto M. ♦ López Fuentes, Marcelo ♦ Nuevo, Federico A. ♦ Landi, Enrico ♦ Frazin, Richard A.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword ASTROPHYSICS, COSMOLOGY AND ASTRONOMY ♦ ALFVEN WAVES ♦ COMPUTERIZED SIMULATION ♦ EMISSION ♦ EXTREME ULTRAVIOLET RADIATION ♦ IMAGES ♦ LIMITING VALUES ♦ MAGNETIC FIELDS ♦ MAGNETOHYDRODYNAMICS ♦ ROTATION ♦ SOLAR CORONA ♦ SUN ♦ TOMOGRAPHY
Abstract We present first results of a novel technique that provides, for the first time, constraints on the energy input flux at the coronal base ( r ∼ 1.025 R {sub ⊙}) of the quiet Sun at a global scale. By combining differential emission measure tomography of EUV images, with global models of the coronal magnetic field, we estimate the energy input flux at the coronal base that is required to maintain thermodynamically stable structures. The technique is described in detail and first applied to data provided by the Extreme Ultraviolet Imager instrument, on board the Solar TErrestrial RElations Observatory mission, and the Atmospheric Imaging Assembly instrument, on board the Solar Dynamics Observatory mission, for two solar rotations with different levels of activity. Our analysis indicates that the typical energy input flux at the coronal base of magnetic loops in the quiet Sun is in the range ∼0.5–2.0 × 10{sup 5} (erg s{sup −1} cm{sup −2}), depending on the structure size and level of activity. A large fraction of this energy input, or even its totality, could be accounted for by Alfvén waves, as shown by recent independent observational estimates derived from determinations of the non-thermal broadening of spectral lines in the coronal base of quiet-Sun regions. This new tomography product will be useful for the validation of coronal heating models in magnetohydrodinamic simulations of the global corona.
ISSN 0004637X
Educational Use Research
Learning Resource Type Article
Publisher Date 2017-07-01
Publisher Place United States
Journal Astrophysical Journal
Volume Number 843
Issue Number 1


Open content in new tab

   Open content in new tab