Title :
Acoustic Events in the Solar Atmosphere
Author :
Malherbe, Jean-Marie ; Roudier, Thierry ; Berger, Thomas ; Frank, Zoe
Author_Institution :
LESIA, Obs. de Paris, Meudon, France
Abstract :
New observations have been obtained on September 4, 2010, by the Solar Optical Telescope on board the satellite HINODE, in the magnetically insensitive Fel 557.6-nm line formed in the solar atmosphere. Acoustic events (AEs, defined as spatially concentrated propagating waves) have been derived in the photosphere from amplitudes and phases of vertical Doppler velocities with outstanding spatial resolution (0.3") and field of view. AEs have a mean lifetime of 500 s and contain about 2 × 1019 J each. Most AEs are upward and occur in intergranular lanes and converging regions associated to permanent plasma downflow. They partly contribute (10%) to energy transport involved in chromospheric heating and could be the drivers of solar oscillations. More than 106 events are simultaneously present on the Sun with a birth/decay rate of 2000 events per second.
Keywords :
chromosphere; photosphere; solar pulsations; AD 2010 09 04; HINODE satellite; Solar Optical Telescope; acoustic events; chromospheric heating; converging region; energy transport; intergranular lane; magnetically insensitive Fe I line; permanent plasma downflow; photosphere; solar atmosphere; solar oscillation; spatial resolution; spatially concentrated propagating waves; vertical Doppler velocity; wavelength 557.6 nm; Acoustics; Atmospheric waves; Manganese; Oscillators; Spatial resolution; Sun; Acoustic waves; astronomy; astrophysics; the Sun;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2011.2154344