On the Relationship Between G-Band Bright Point Dynamics and Their Magnetic Field Strengths

Abstract

G-band bright points (GBPs) are regarded as good manifestations of magnetic flux concentrations. We aim to investigate the relationship between the dynamic properties of GBPs and their longitudinal magnetic field strengths. High spatial and temporal resolution observations were recorded simultaneously with G-band filtergrams and Narrow-band Filter Imager (NFI) Stokes I and V images with Hinode /Solar Optical Telescope. The GBPs are identified and tracked in the G-band images automatically, and the corresponding longitudinal magnetic field strength of each GBP is extracted from the calibrated NFI magnetograms by a point-to-point method. After categorizing the GBPs into five groups by their longitudinal magnetic field strengths, we analyze the dynamics of GBPs of each group. The results suggest that with increasing longitudinal magnetic field strengths of GBPs correspond to a decrease in their horizontal velocities and motion ranges as well as by showing more complicated motion paths. This suggests that magnetic elements showing weaker magnetic field strengths prefer to move faster and farther along straighter paths, while stronger ones move more slowly in more erratic paths within a smaller region. The dynamic behaviors of GBPs with different longitudinal magnetic field strengths can be explained by that the stronger flux concentrations withstand the convective flows much better than weaker ones.

Characterizing the Motion of Solar Magnetic Bright Points at High Resolution

“…These features were considered by van Ballegooijen et al (1998), but they generally require a different approach than that used in this paper for small, isolated bright points. Differences may be expected between the dynamics of the isolated and the extended types of bright points, due to both interactions between flux elements in extended structures, and the observed trend for bright points to move more slowly in regions of increased magnetic flux (Ji et al 2016;Yang et al 2016).…”

Studies of Isolated and Non-isolated Photospheric Bright Points in an Active Region Observed by the New Vacuum Solar Telescope

“…Therefore, a BP is the interaction of a magnetic flux tube with the photosphere, and can thus be thought of as a tracer of the footpoint of magnetic flux tubes in the photosphere (Berger et al 1998;De Pontieu 2002;Schüssler et al 2003;Beck et al 2007;Yang et al 2016). BPs, therefore, play a key role in helping to investigate various behaviors of the magnetic elements in the photosphere, and further our understanding the physics of these behaviors.…”

Observational Evidence of Magnetic Reconnection for Brightenings and Transition Region Arcades in IRIS Observations

“…Such events take place in different atmospheric layers from the photosphere to the corona (Harrison 1997;Berger et al 2007;Chandrashekhar et al 2013), and ubiquitous in active regions, quiet Sun and coronal holes (Shimizu 1995;Zhang et al 2001;Kamio et al 2011). With the ground-based and space telescopes, photospheric BPs are often studied to investigate the condition of the convective flows in and below the photosphere (Feng et al 2013;Jafarzadeh et al 2014;Yang et al 2015Yang et al , 2016Ji et al 2016a,b). These flows are widely accepted to be the ultimate source of the energy; coronal BPs as well as coronal loops are also frequently discussed (Li et al 2013;Zhang et al 2014;Alipour & Safari 2015;Chesny et al 2015;Mou et al 2016) as they were thought to be the most potential candidates for coronal heating.…”