Magnetic Helicity Signs and Flaring Propensity: Comparing Force-free Parameter with the Helicity signs of Hα Filaments and X-ray Sigmoids

V. Aparna, Manolis K. Georgoulis, Petrus C. Martens

Sigmoids produce strong eruptive events. Earlier studies have shown that the ICME axial magnetic field Bz can be predicted with some credibility by observing the corresponding fila…