LECTURER: Sergio Javier González Manrique

TITLE: Magnetic Connectivity and Chromospheric Acceleration
       in an Arch Filament System Observed with Sunrise III

ABSTRACT:
Emerging flux regions (EFRs) are key sites of magnetic flux
transport and energy release in the solar atmosphere, often
hosting arch filament systems (AFSs) and filamentary structures.
We present high-resolution, multi-line observations of an EFR
obtained during the Sunrise III mission, combining spectropolarimetric
measurements from TuMag and SCIP with complementary EUV observations
from SDO. The dataset provides a continuous view of the temporal
evolution of an AFS over nearly four hours. Line-of-sight velocities
derived from the Mg I b2 line reveal distinct phases of plasma
acceleration, with strong downflows reaching up to 17 km/s at
the AFS footpoints. These episodes are co-temporal with brightenings
observed in AIA 171 Å and 304 Å channels. Multi-line spectropolarimetric
inversions indicate a magnetic configuration consistent with arch
filament structures, while non-force-free-field extrapolations
reveal an evolving topology, including regions where field lines
from different domains converge. The temporal proximity between
the filament eruption and the enhanced plasma dynamics suggests
a possible interaction, although a direct causal relationship cannot
be established. The observed acceleration may be explained either
by plasma draining from higher atmospheric layers or by plasma
redistribution along complex magnetic connectivity. These results
highlight the importance of multi-line, high-resolution observations
for understanding the coupling between magnetic field evolution
and plasma dynamics in EFRs.