The issues related to moving elements in space and instruments working inbroader wavelength ranges lead to a need for robust polarimeters, efficient ona wide spectral domain, and adapted to space conditions. As part of the UVMagconsortium, created to develop spectropolarimetric UV facilities in space, suchas the Arago mission project, we present an innovative concept of staticspectropolarimetry. We studied a static and polychromatic method forspectropolarimetry, applicable to stellar physics. Instead of modulating thepolarization information temporally, as usually done in spectropolarimeters,the modulation is performed in a spatial direction, orthogonal to the spectralone. Thanks to the proportionality between phase retardance imposed by abirefringent material and its thickness, birefringent wedges can be used tocreate this spatial modulation. The light is then spectrally cross-dispersed,and a full-Stokes determination of the polarization over the whole spectrum canbe obtained with a single-shot measurement. The use of Magnesium Fluoridewedges, for example, could lead to a compact, static polarimeter working atwavelengths from 0.115 mm up to 7 mm. We present the theory and simulations ofthis concept, as well as laboratory validation and a practical application toArago.
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