Researchers determine bright-magnetic relationship for decaying sunspots

Prof. Yan Xiaoli from Yunnan Observatories of the Chinese language Academy of Sciences and Li Qiaoling, a post-doctor from Yunnan College, have decided the bright-magnetic relationship for decaying sunspots for the primary time.

Associated outcomes have been printed in The Astrophysical Journal.

The brightness of sunspots is a vital parameter within the research of the total irradiance of the sun and a key index to confirm the dynamics and magnetic properties of sunspots. The connection between sunspot brightness and its magnetic field strength is named the bright-magnetic relationship.

The research of the bright-magnetic relationship of sunspots is useful to know the brightness and atmospheric construction of sunspots, and supplies constraints for the theoretical mannequin of the power transport mechanism of sunspots.

Earlier observational research on the bright-magnetic relationship of sunspots have largely centered on steady sunspots, and few have studied the bright-magnetic relationship of decaying sunspots.

The researchers analyzed the distinction of the bright-magnetic relationship between the steady and decaying sunspots by utilizing the stray mild calibration information from the Photo voltaic Dynamics Observatory Helioseismic and Magnetic Imaging.

They discovered that the distinction of the bright-magnetic relationship between steady and decaying sunspots was primarily manifested within the continuum intensity (brightness) vary from 0.35 Iqs to 0.65 Iqs (Iqs is the common continuum depth of the quiet sun). Within the decaying sunspot, the connection between the continuum depth and the transverse magnetic subject energy confirmed the next diploma of dispersion.

“We additionally discovered a bifurcation construction within the relationship between the continuum depth and the transverse magnetic subject energy throughout the formation of the sunshine bridge. This bifurcation construction signifies that the 2 components of the umbra separated by the sunshine bridge have completely different thermodynamic properties,” mentioned Prof. Yan.

“The continuum depth of the sunspot umbra in decaying sunspots is brighter than that of a steady sunspot, and the imply continuum depth of the sunspot umbra regularly will increase throughout the decay of sunspot. Nevertheless, the imply continuum depth of the penumbra doesn’t change with the decay of the sunspot,” mentioned Li.

These outcomes point out that throughout the decay of sunspot, the temperature of the umbra will increase regularly, however the temperature of the penumbra stays fixed.