Observations of a rotating macrospicule associated with an X-ray jet

Abstract

Aims: We attempt to understand the driving mechanism of a macrospicule and its relationship with a coronal jet. Methods: We study the dynamics of a macrospicule and an associated coronal jet captured by multi-spacecraft observations. Doppler velocities in both the macrospicule and the coronal jet are determined by EIS and SUMER spectra. Their temporal evolution is studied using X-ray and He ii λ304 images. Results: A blueshift of -120 ± 15 km s-1 is detected on one side of the macrospicule, while a redshift of 50 ±6 km s-1 is found at the base of the other side. The inclination angle of the macrospicule inferred from a stereoscopic analysis with STEREO suggests that the measured Doppler velocities can be attributed to a rotating motion of the macrospicule rather than a radial flow or an expansion. Conclusions: The macrospicule is driven by the unfolding motion of a twisted magnetic flux rope, while the associated X-ray jet is a radial outflow. © 2010 ESO.