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arXiv · 2509.01678

Investigating the role of magnetic fields in the formation and evolution of striations in interstellar clouds with PRIMA

Abstract

Striations are diffuse, linear, quasi-periodic, and magnetized structures located in the outskirts of molecular clouds. These structures seem to play an important role during the earliest stages of star formation. Theoretical models suggest that magnetic fields play an important role in the formation of striations. With its unprecedented resolution and sensitivity, the polarization module of the PRIMAger instrument onboard the PRIMA space observatory will enable studies related to the magnetic properties of striations in nearby molecular clouds. We plan to target three nearby ($\lesssim 350$ pc) molecular clouds (the Polaris Flare, Taurus, and Musca) with prominent striations that are strongly coupled to the large-scale magnetic field properties, as traced by low-resolution sub-millimeter polarization data. We will search for the unique imprint of the passage of magnetohydrodynamic waves in the polarization angle maps, which traces the magnetic field morphology, in bands 3 (172$μ$m) and 4 (235$μ$m) of PRIMAger. Each of the target regions is approximately 1 square degree in size. All three regions combined, can be mapped to more than five-sigma detection in averaged polarized intensity in $\sim 59$ hours. The proposed survey promises to provide important information on the early phases of star formation.

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Raphael Skalidis, Konstantinos Tassis, Aris Tritsis, Paul F Goldsmith. 2025-09-01. Investigating the role of magnetic fields in the formation and evolution of striations in interstellar clouds with PRIMA. https://doi.org/10.1117/1.jatis.11.3.031617

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