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arXiv · 2103.01583

Mapping Solar Magnetic Fields from the Photosphere to the Base of the Corona

Ryohko Ishikawa·Javier Trujillo Bueno·Tanausu del Pino Aleman·Takenori J. Okamoto·David E. McKenzie·Frederic Auchere·Ryouhei Kano·Donguk Song·Masaki Yoshida·Laurel A. Rachmeler·Ken Kobayashi·Hirohisa Hara·Masahito Kubo·Noriyuki Narukage·Taro Sakao·Toshifumi Shimizu·Yoshinori Suematsu·Christian Bethge·Bart De Pontieu·Alberto Sainz Dalda·Genevieve D. Vigil·Amy Winebarger·Ernest Alsina Ballester·Luca Belluzzi·Jiri Stepan·Andres Asensio Ramos·Mats Carlsson·Jorrit Leenaarts
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Abstract

Routine ultraviolet imaging of the Sun's upper atmosphere shows the spectacular manifestation of solar activity; yet we remain blind to its main driver, the magnetic field. Here we report unprecedented spectropolarimetric observations of an active region plage and its surrounding enhanced network, showing circular polarization in ultraviolet (Mg II $h$ & $k$ and Mn I) and visible (Fe I) lines. We infer the longitudinal magnetic field from the photosphere to the very upper chromosphere. At the top of the plage chromosphere the field strengths reach more than 300 gauss, strongly correlated with the Mg II $k$ line core intensity and the electron pressure. This unique mapping shows how the magnetic field couples the different atmospheric layers and reveals the magnetic origin of the heating in the plage chromosphere.

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Ryohko Ishikawa, Javier Trujillo Bueno, Tanausu del Pino Aleman, Takenori J. Okamoto, David E. McKenzie, Frederic Auchere, Ryouhei Kano, Donguk Song, Masaki Yoshida, Laurel A. Rachmeler, Ken Kobayashi, Hirohisa Hara, Masahito Kubo, Noriyuki Narukage, Taro Sakao, Toshifumi Shimizu, Yoshinori Suematsu, Christian Bethge, Bart De Pontieu, Alberto Sainz Dalda, Genevieve D. Vigil, Amy Winebarger, Ernest Alsina Ballester, Luca Belluzzi, Jiri Stepan, Andres Asensio Ramos, Mats Carlsson, Jorrit Leenaarts. 2021-03-02. Mapping Solar Magnetic Fields from the Photosphere to the Base of the Corona. https://doi.org/10.1126/sciadv.abe8406

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