Magnetic properties of short-lived penumbral microjets
Abstract
Penumbral microjets (PMJs) are fast elongated brightenings above sunspots penumbrae. They are presumed to be related to photospheric magnetic reconnection processes and contribute to the heating of the plasma in the higher atmospheric layers. Studying the spectral and polarization properties of the shortest-living microjets requires the fastest temporal cadence possible and is currently a challenging task. In this work, we use fast spectropolarimetric measurements of the Ca II 8542 A line made with the CRISP instrument at the Swedish 1 m Solar Telescope, and exploit the diagnostic capabilities of this line to retrieve the magnetic field configuration and its evolution at different atmospheric heights during PMJs. Our findings show that short-lived PMJs are associated with a transient perturbation in the photospheric magnetic field and sometimes they show clear but weaker changes in the chromospheric field as well. We will describe the different types of evolution that were identified. These results support the idea that PMJs may be the result of magnetic reconnection at low altitudes in sunspot penumbra.
- Publication:
-
44th COSPAR Scientific Assembly. Held 16-24 July
- Pub Date:
- July 2022
- Bibcode:
- 2022cosp...44.2520T