TuMag: the tunable magnetograph for the Sunrise III mission
Abstract
One of the instruments aboard the Sunrise III mission, the Tunable Magnetograph (TuMag), is a tunable imaging spectropolarimeter in visible wavelengths. It is designed to probe the vector magnetic field and the line-of-sight velocity of the photosphere and the lower chromosphere. The quasi-simultaneous observation of two spectral lines provides excellent diagnostic measurements of the magnetic and dynamic coupling in these layers. The key technologies employed for TuMag are an LCVR-based polarimeter and a solid, LiNbO3 Fabry-P\'erot etalon as a spectrometer. However, it also incorporates several innovative features, such as home-made high-sensitivity scientific cameras and a double filter wheel. TuMag can sequentially observe any two out of the three spectral lines of Fe I at 525.02 and 525.06 nm and of Mg I at 517.3 nm. Laboratory measurements have demonstrated outstanding performance, including a wavefront root-mean-square error better than {\lambda}/13 for image quality, a full-width-at-half-maximum of 8.7 pm for the filtergraph transmission profile, and polarimetric efficiencies > 0.54. Here we report on the concept, design, calibration, and integration phases of the instrument, as well as on the data reduction pipeline.
Keywords
Cite
@article{arxiv.2502.08268,
title = {TuMag: the tunable magnetograph for the Sunrise III mission},
author = {J. C. del Toro Iniesta and D. Orozco Suárez and A. Álvarez-Herrero and E. Sanchis Kilders and I. Pérez-Grande and B. Ruiz Cobo and L. R. Bellot Rubio and M. Balaguer Jiménez and A. C. López Jiménez and D. Álvarez García and J. L. Ramos Más and J. P. Cobos Carrascosa and P. Labrousse and A. J. Moreno Mantas and J. M. Morales-Fernández and B. Aparicio del Moral and A. Sánchez Gómez and E. Bailón Martínez and F. J. Bailén and H. Strecker and A. L. Siu-Tapia and P. Santamarina Guerrero and A. Moreno Vacas and J. Atiénzar García and A. J. Dorantes Monteagudo and I. Bustamante and A. Tobaruela and A. Fernández-Medina and A. Núñez Peral and M. Cebollero and D. Garranzo-García and P. García Parejo and A. Gonzalo Melchor and A. Sánchez Rodríguez and A. Campos-Jara and H. Laguna and M. Silva-López and J. Blanco Rodríguez and J. L. Gasent Blesa and P. Rodríguez Martínez and A. Ferreres and D. Gilabert Palmer and I. Torralbo and J. Piqueras and D. González-Bárcena and A. J. Fernández and D. Hernández Expósito and E. Páez Mañá and E. Magdaleno Castelló and M. Rodríguez Valido and Andreas Korpi-Lagg and Achim Gandorfer and Sami K. Solanki and Thomas Berkefeld and Pietro Bernasconi and Alex Feller and Yukio Katsukawa and Tino L. Riethmüller and H. N. Smitha and Masahito Kubo and Valentín Martínez Pillet and Bianca Grauf and Alexander Bell and Michael Carpenter},
journal= {arXiv preprint arXiv:2502.08268},
year = {2025}
}
Comments
Contains 58 pages and 25 figures; to be published in Solar Physics Topical Collection "The Sunrise III Solar Observatory" (https://link.springer.com/collections/jegdciedig)