UV1600 bright points and magnetic bipoles in solar quiet regions

Abstract

Using the observations from Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamics Observatory (SDO), we explore the relationship between the bright points at 1600 (1600BPs) and magnetic polarities in the quiet regions of the Sun. 1600BPs are determined from the bright regions with a brightness above the mean value of the background plus the three times of background deviation and with an area above 25 pixel(2) (9.324 arcsec(2)), while individual magnetic polarity has a strength greater than the mean value of the background plus the two and half times of background deviation and an area greater than 5 pixel(2) (1.272 arcsec(2)). And magnetic bipoles are identified as a pair of positive and negative polarities with a shortest distance between them. Based on this way, 2722 1600BPs and 2850 magnetic bipoles are identified from double square regions near disk center but symmetrically on north- and south-hemispheres respectively, with a size of 200''Au200'' each day from 19 to 25 August 2010. We find that only 29.6 % (806/2722) 1600BPs display a good correlation with magnetic bipoles, while about 64.3 % (1749/2722) 1600BPs show one-to-one correspondence to the magnetic polarities, regardless of the positive and negative polarities. For these magnetic bipoles associated with 1600BPs, we find that their orientation angles are distributed randomly along the equator.