Instituto de Astrofísica de Andalucía (IAA-CSIC)

The history of a quiet-Sun magnetic element revealed by IMaX/Sunrise                                                            

For the first time, researchers observe the formation and evolution of a resolved quiet-Sun magnetic element 

13/05/2014

Isolated flux tubes are considered to be fundamental magnetic building blocks of the solar photosphere. Their formation is usually attributed to the concentration of magnetic field to kG strengths by the convective collapse mechanism. However, the small size of the magnetic elements in quiet-Sun areas has prevented this scenario from being studied in fully resolved structures. In this paper we present the most detailed study of the formation and subsequent evolution of one such photospheric magnetic flux tube. This has been only possible thanks to the unprecedented spatial resolution (0”.15 - 0”.18) and high temporal cadence (33 s) acquired by the Imaging Magnetograph Experiment (IMaX) aboard the Sunrise balloon-borne solar observatory. Such resolution has highlighted  the complex nature of magnetic elements in the quiet Sun, whose formation and evolution includes flux concentration by granular advection, the above mentioned convective collapse, and oscillatory-like behavior as the final state of a collapsed flux tube. 

Figure caption: This image shows the horizontal velocity maps derived through the local correlation tracking technique averaged over the formation and evolution of the magnetic element. Proper motions of the continuum intensity, line-of-sight  velocity, and circular polarization are displayed. The images are averaged in time over the whole data set (~23 min). Click on image to view the whole temporal sequence. 

Reference: Requerey et al. (2014), ApJ 789 6
The history of a quiet-Sun magnetic element revealed by IMaX/Sunrise