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arXiv · 2111.06891

UV Spectropolarimetry with Polstar: Protoplanetary Disks

John P. Wisniewski·Andrei V. Berdyugin·Svetlana V. Berdyugina·William C. Danchi·Ruobing Dong·Rene D. Oudmaijer·Vladimir S. Airapetian·Sean D. Brittain·Ken Gayley·Richard Ignace·Maud Langlois·Kellen D. Lawson·Jamie R. Lomax·Motohide Tamura·Jorick S. Vink·Paul A. Scowen
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Abstract

Polstar is a proposed NASA MIDEX mission that would feature a high resolution UV spectropolarimeter capable of measure all four Stokes parameters onboard a 60cm telescope. The mission would pioneer the field of time-domain UV spectropolarimetry. Time domain UV spectropolarimetry offers the best resource to determine the geometry and physical conditions of protoplanetary disks from the stellar surface to <5 AU. We detail two key objectives that a dedicated time domain UV spectropolarimetry survey, such as that enabled by Polstar, could achieve: 1) Test the hypothesis that magneto-accretion operating in young planet-forming disks around lower-mass stars transitions to boundary layer accretion in planet-forming disks around higher mass stars; and 2) Discriminate whether transient events in the innermost regions of planet-forming disks of intermediate mass stars are caused by inner disk mis-alignments or from stellar or disk emissions.

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John P. Wisniewski, Andrei V. Berdyugin, Svetlana V. Berdyugina, William C. Danchi, Ruobing Dong, Rene D. Oudmaijer, Vladimir S. Airapetian, Sean D. Brittain, Ken Gayley, Richard Ignace, Maud Langlois, Kellen D. Lawson, Jamie R. Lomax, Motohide Tamura, Jorick S. Vink, Paul A. Scowen. 2021-11-12. UV Spectropolarimetry with Polstar: Protoplanetary Disks. https://doi.org/10.1007/s10509-022-04125-7

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