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arXiv · 2502.08268

TuMag: the tunable magnetograph for the Sunrise III mission

J. C. del Toro Iniesta·D. Orozco Suárez·A. Álvarez-Herrero·E. Sanchis Kilders·I. Pérez-Grande·B. Ruiz Cobo·L. R. Bellot Rubio·M. Balaguer Jiménez·A. C. López Jiménez·D. Álvarez García·J. L. Ramos Más·J. P. Cobos Carrascosa·P. Labrousse·A. J. Moreno Mantas·J. M. Morales-Fernández·B. Aparicio del Moral·A. Sánchez Gómez·E. Bailón Martínez·F. J. Bailén·H. Strecker·A. L. Siu-Tapia·P. Santamarina Guerrero·A. Moreno Vacas·J. Atiénzar García·A. J. Dorantes Monteagudo·I. Bustamante·A. Tobaruela·A. Fernández-Medina·A. Núñez Peral·M. Cebollero·D. Garranzo-García·P. García Parejo·A. Gonzalo Melchor·A. Sánchez Rodríguez·A. Campos-Jara·H. Laguna·M. Silva-López·J. Blanco Rodríguez·J. L. Gasent Blesa·P. Rodríguez Martínez·A. Ferreres·D. Gilabert Palmer·I. Torralbo·J. Piqueras·D. González-Bárcena·A. J. Fernández·D. Hernández Expósito·E. Páez Mañá·E. Magdaleno Castelló·M. Rodríguez Valido·Andreas Korpi-Lagg·Achim Gandorfer·Sami K. Solanki·Thomas Berkefeld·Pietro Bernasconi·Alex Feller·Yukio Katsukawa·Tino L. Riethmüller·H. N. Smitha·Masahito Kubo·Valentín Martínez Pillet·Bianca Grauf·Alexander Bell·Michael Carpenter
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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.

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J. C. del Toro Iniesta, D. Orozco Suárez, A. Álvarez-Herrero, E. Sanchis Kilders, I. Pérez-Grande, B. Ruiz Cobo, L. R. Bellot Rubio, M. Balaguer Jiménez, A. C. López Jiménez, D. Álvarez García, J. L. Ramos Más, J. P. Cobos Carrascosa, P. Labrousse, A. J. Moreno Mantas, J. M. Morales-Fernández, B. Aparicio del Moral, A. Sánchez Gómez, E. Bailón Martínez, F. J. Bailén, H. Strecker, A. L. Siu-Tapia, P. Santamarina Guerrero, A. Moreno Vacas, J. Atiénzar García, A. J. Dorantes Monteagudo, I. Bustamante, A. Tobaruela, A. Fernández-Medina, A. Núñez Peral, M. Cebollero, D. Garranzo-García, P. García Parejo, A. Gonzalo Melchor, A. Sánchez Rodríguez, A. Campos-Jara, H. Laguna, M. Silva-López, J. Blanco Rodríguez, J. L. Gasent Blesa, P. Rodríguez Martínez, A. Ferreres, D. Gilabert Palmer, I. Torralbo, J. Piqueras, D. González-Bárcena, A. J. Fernández, D. Hernández Expósito, E. Páez Mañá, E. Magdaleno Castelló, M. Rodríguez Valido, Andreas Korpi-Lagg, Achim Gandorfer, Sami K. Solanki, Thomas Berkefeld, Pietro Bernasconi, Alex Feller, Yukio Katsukawa, Tino L. Riethmüller, H. N. Smitha, Masahito Kubo, Valentín Martínez Pillet, Bianca Grauf, Alexander Bell, Michael Carpenter. 2025-02-12. TuMag: the tunable magnetograph for the Sunrise III mission. https://arxiv.org/abs/2502.08268

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