Homologous Helical Jets: Observations by IRIS, SDO and Hinode and Data-Driven Simulations

Friday, 19 December 2014: 2:40 PM
Chun Ming Mark Cheung1, Bart De Pontieu1, Theodore D Tarbell1 and Yixing Fu2, (1)Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA, United States, (2)University of California Berkeley, Berkeley, CA, United States
We report on observations of recurrent jets by instruments onboard the Interface Region Imaging Spectrograph (IRIS), Solar Dynamics Observatory (SDO) and Hinode spacecrafts. Over a 4-hour period on July 21st 2013, recurrent coronal jets were observed to emanate from NOAA Active Region 11793. In more than one instance, double-peaked FUV spectra probing plasma at transition region temperatures show evidence of oppositely directed (Doppler) outflows exceeding +/- 100 km/s. Raster Doppler maps using a Si IV transition region line shows all four jets to have helical motion of the same sense. Time-dependent data-driven simulations are used to investigate the underlying drivers for the jets. These numerical experiments show that the emergence of current-carrying magnetic field in the vicinity of a pore supplies the magnetic twist needed for recurrent helical jet formation.