Speaker
Description
First Name: Myrto
Last Name: Koletti
Affiliation: NKUA/ Academy of Athens
All Authors: Gontikakis C, Patsourakos S, Tsinganos K
Abstract: We present a comprehensive multi-height spectroscopic analysis of a coronal hole jet ob- served on October 9, 2013, using data from the Interface Region Imaging Spectrograph (IRIS) and the Solar Dynamics Observatory (SDO). The event, occurring in an equatorial coronal hole, was associated with the activation and eruption of a mini-filament. Chromospheric diag- nostics were derived from the Mg II k 2796 ˚A line using genetic-algorithm spectral fitting and non-LTE inversions (IRIS2/STiC), while transition-region properties were obtained from the Si IV 1393 ˚A line. Our results show that the jet was initiated by the destabilization of the mini-filament, fol- lowed by magnetic reconnection below the mini-filament and subsequently via interchange reconnection with open field lines. We detect strong downflows at one footpoint of the mini- filament—interpreted as plasma drainage—together with simultaneous upflows in the jet spire. Statistical correlations between Mg II and Si IV diagnostics reveal that larger Mg II peak separa- tions and deeper core reversals correspond to enhanced velocity gradients and stronger upflows, indicating a connection between chromospheric and transition-region dynamics. This work confirms that small-scale magnetic reconnection associated with mini-filament eruptions is a key driver of coronal hole jets and demonstrate that their signatures can be traced down to the lower chromosphere.