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arXiv · 1009.1050

Quiet-Sun intensity contrasts in the near ultraviolet

Johann Hirzberger·Alex Feller·Tino L. Riethmüller·Manfred Schüssler·Juan M. Borrero·Nadine Afram·Yvonne C. Unruh·Svetlana V. Berdyugina·Achim Gandorfer·Sami K. Solanki·Peter Barthol·Jose A. Bonet·Valentin Martínez Pillet·Thomas Berkefeld·Michael Knölker·Wolfgang Schmidt·Alan M. Title
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Abstract

We present high-resolution images of the Sun in the near ultraviolet spectral range between 214 nm and 397 nm as obtained from the first science flight of the 1-m Sunrise balloon-borne solar telescope. The quiet-Sun rms intensity contrasts found in this wavelength range are among the highest values ever obtained for quiet-Sun solar surface structures - up to 32.8% at a wavelength of 214 nm. We compare with theoretical intensity contrasts obtained from numerical magneto-hydrodynamic simulations. For 388 nm and 312 nm the observations agree well with the numerical simulations whereas at shorter wavelengths discrepancies between observed and simulated contrasts remain.

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Johann Hirzberger, Alex Feller, Tino L. Riethmüller, Manfred Schüssler, Juan M. Borrero, Nadine Afram, Yvonne C. Unruh, Svetlana V. Berdyugina, Achim Gandorfer, Sami K. Solanki, Peter Barthol, Jose A. Bonet, Valentin Martínez Pillet, Thomas Berkefeld, Michael Knölker, Wolfgang Schmidt, Alan M. Title. 2010-09-06. Quiet-Sun intensity contrasts in the near ultraviolet. https://arxiv.org/abs/1009.1050

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