Magnetic topology of blinkers*
Armagh Observatory, College Hill, Armagh BT61 9DG, N. Ireland
2 Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau, Germany
3 Space Physics Division, Space Science and Technology Department, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK
Accepted: 17 June 2008
Context. Co-spatial and co-temporal spectroscopic, imaging and magnetogram data enable us to better understand various solar transient phenomena. Here, we study brightening events in the transition region of the quiet Sun, also called “blinkers”.
Aims. We aim to investigate the physical mechanism responsible for blinkers.
Methods. An automated blinker identification procedure (BLIP) is used to identify blinker events in SoHO/CDS data. The 3D magnetic topology of the magnetic field in the blinker region is reconstructed based on SoHO/MDI magnetogram data.
Results. During 3 h of SoHO/CDS observations on 2006 January 18, 66 blinkers were identified in the O v 629 Å emission line. Out of them, a group comprising of 16 events were modelled here. They were found to be associated with the emergence of magnetic flux which gave rise to the appearance of, and multiple magnetic reconnection events across, an upper atmosphere (coronal) magnetic null point, along with a loop structure as observed with TRACE.
Conclusions. This blinker group results from the release of energy that was accumulated during flux emergence, although whether all blinkers follow the same formation scenario requires further investigation using additional multi-instrument/multi-mission studies.
Key words: Sun: activity / Sun: UV radiation / Sun: transition region / Sun: atmosphere / Sun: corona / Sun: magnetic fields
© ESO, 2008