Prominence Formation Associated with an Emerging Helical Flux Rope

Abstract

The formation and evolution process and magnetic configuration of solar prominences remain unclear. In order to study the formation process of prominences, we examine continuous observations of a prominence in NOAA AR 10953 with the Solar Optical Telescope on the Hinode satellite. As reported in our previous Letter, we find a signature suggesting that a helical flux rope emerges from below the photosphere under a pre-existing prominence. Here we investigate more detailed properties and photospheric indications of the emerging helical flux rope, and discuss their relationship to the formation of the prominence. Our main conclusions are: (1) A dark region with absence of strong vertical magnetic fields broadens and then narrows in Ca ii H-line filtergrams. This phenomenon is consistent with the emergence of the helical flux rope as photospheric counterparts. The size of the flux rope is roughly 30,000 km long and 10,000 km wide. The width is larger than that of the prominence. (2) No shear motion or converging flows are detected, but we find diverging flows such as mesogranules along the polarity inversion line. The presence of mesogranules may be related to the emergence of the helical flux rope. (3) The emerging helical flux rope reconnects

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Cite this paper

@inproceedings{Okamoto2009ProminenceFA, title={Prominence Formation Associated with an Emerging Helical Flux Rope}, author={Takenori J. Okamoto and Saku Tsuneta and Bruce W . Lites and Masahito Mogami Kubo and Takaaki Yokoyama and Thomas E. Berger and K. Ichimoto and Yukio Katsukawa and Shin’ichi Nagata and Kazunari Shibata and Toshifumi Shimizu and Richard Shine and Yoshinori Suematsu and Theodore D. Tarbell}, year={2009} }