(News & views on the paper by Jun-Chao Hong et al., RAA, 2013, vol.13, 253-258)
Coupling of a blowout jet with a prominence eruption and a CME
(Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012)
Coronal jets are omnipresent over the Sun’s surface. It is widely accepted that numerous jets are produced by magnetic reconnection between a newly emerging dipole and an ambient open field (Yokoyama & Shibata 1996), and many previous observations have shown that some jets even exhibit helical structures and untwisting motions, which are explained as due to twist in the closed dipole field being transferred into the open field by reconnection (Canfield et al. 1996). However, Moore et al. (2010) have presented a new type of jet, called a ``blowout jet,’’ which corresponds to erupting-loop Hα macrospicules. Therefore, blowout jets are different from standard jets that fit the reconnection model between an emerging dipole and an open field. Moreover, it is expected that the untwisting behavior in blowout jets may also originate from a different mechanism than that in standard jets.
By analyzing multi-angle observations of a polar blowout jet, a new idea is proposed by Hong et al. (2013) for untwisting in a polar blowout jet. Their results indicate that the twist in the blowout jet may come from a mini-prominence at the jet base and be released by its eruption. Following this conclusion, they further infer that (1) there would be a one-to-one relationship between twist handedness in the blowout jet (Jibben & Canfield 2004) and filament chirality (Martin et al. 1994), namely a left/right–handed-twist blowout jet corresponds to a dextral/sinistral filament, and (2) the twist handedness of blowout jets would have a hemispheric preference because of the hemispheric pattern for filament chirality. Furthermore, the blowout jet also leads to a narrow coronal mass ejection (CME), which extends to 1.5 solar radii.
The work of Hong et al. (2013) clearly displays the whole process involved with a series of small scale activities, indicating that there exists coupling between different kinds of activities in the solar atmosphere.