Penumbral Waves driving Solar chromospheric fan-shaped jets [SSA]

http://arxiv.org/abs/1802.07537


We use H$\alpha$ imaging spectroscopy taken via the Swedish 1-m Solar Telescope (SST) to investigate the occurrence of fan-shaped jets at the solar limb. We show evidence for near-simultaneous photospheric reconnection at a sunspot edge leading to the jets appearance, with upward velocities of 30\ks, and extensions up to 8~Mm. The brightening at the base of the jets appears recurrent, with a periodicity matching that of the nearby sunspot penumbra, implying running penumbral waves could be the driver of the jets. The jets’ constant extension velocity implies that a driver counteracting solar gravity exists, possibly as a result of the recurrent reconnection erupting material into the chromosphere. These jets also show signatures in higher temperature lines captured from the Solar Dynamics Observatory (SDO), indicating a very hot jet front, leaving behind optically thick cool plasma in its wake.

Read this paper on arXiv…

A. Reid, V. Henriques, M. Mathioudakis, et. al.
Thu, 22 Feb 18
9/60

Comments: Accepted into ApjL. 5 Figures with 1 movie