Magnetic Field and Heating of Magnetic Field and Heating of the Coronathe Corona

Valentyna Abramenko and Vasyl Valentyna Abramenko and Vasyl YurchyshynYurchyshyn

Big Bear Solar ObservatoryBig Bear Solar Observatory

Soft X-ray luminosity of the Soft X-ray luminosity of the corona corona

Active Regions: Active Regions: Total unsigned Total unsigned magnetic flux versus Soft X-ray fluxmagnetic flux versus Soft X-ray flux

Abramenko, Pevtsov, Romano 2006Abramenko, Pevtsov, Romano 2006

Structural parameters of the magnetic field versus Structural parameters of the magnetic field versus the area-averaged X-ray flux in the Al1.1 channelthe area-averaged X-ray flux in the Al1.1 channel

Abramenko , 2007Abramenko , 2007

Time variations of the power index and flatness Time variations of the power index and flatness index from SOT/FG/Hinode magnetograms for NOAA index from SOT/FG/Hinode magnetograms for NOAA

1093010930Abramenko & Yurchyshyn, 2007Abramenko & Yurchyshyn, 2007

Poynting Flux vs X-ray Flux:Poynting Flux vs X-ray Flux:area-averaged valuesarea-averaged values

Follow-up study: Tan, Jing, Abramenko, Pevtsov, Song, Park, Wang, 2007 ApJ

Poynting Flux ~ Bh Bz Vh

Bz Bz Vh

Total unsigned magnetic flux versus X-ray Total unsigned magnetic flux versus X-ray luminosity for different objectsluminosity for different objects

Pevtsov et al. 2003Pevtsov et al. 2003

Coronal Holes: Magnetic flux versus the Coronal Holes: Magnetic flux versus the corresponding solar wind speedcorresponding solar wind speed

Abramenko & Yurchyshyn 2007Abramenko & Yurchyshyn 2007

•ConclusionsConclusions

Energy input due to the random motions Energy input due to the random motions strongly correlates with brightness, strongly correlates with brightness, temperature and emission measure of the temperature and emission measure of the corona.corona.

Energy flux is (1 ÷ 14)×10Energy flux is (1 ÷ 14)×1066 erg cm erg cm-2-2 s s-1-1, which , which is quite sufficient to heat the corona above is quite sufficient to heat the corona above ARs.ARs.

Magnetic diffusivity in ARs is Magnetic diffusivity in ARs is (150 ÷ 300) km2/s, which is twice lower than in QS areas., which is twice lower than in QS areas.

Magnetic dissipation versus Magnetic dissipation versus temperature and emission temperature and emission

measuremeasure

Magnetic dissipation versus averaged Magnetic dissipation versus averaged flux in Al.1 and AlMgMn channelsflux in Al.1 and AlMgMn channels

Flux d

ensi

ty (

Al.1

)

Flux d

ensi

ty (

AlM

gM

n)