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arXiv · 2509.25341

Seeking Kinematic Association of Known FU Orionis Stars with Young Clusters in Cygnus

Tamojeet Roychowdhury·Lynne A. Hillenbrand
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Abstract

Kinematic studies of young stars and star clusters have increased our understanding of the process of star formation and evolution in the Milky Way. FU Orionis objects are a specific class of young stellar object notable for their extremely high disk-to-star accretion rates. We use parallax and proper motion information from the Gaia astrometric survey to study five known FU Ori stars towards the Cygnus clouds, in the distance range ~500-900 parsecs, and seek evidence of their kinematic association with proximal stellar groups or clusters. We develop multiple search criteria within the Gaia datasets to look for nearby stellar aggregates and to reliably isolate their likely member stars. We show that V1057 Cygni and HBC 722 are kinematically consistent with the 3D locations as well as the inferred proper motion fields of the North America Nebula cluster. We show a similar association of V1515 Cygni with NGC 6914 in the Cygnus-X region, and of V2494 Cygni with stars in the dark cloud LDN 1003 and Braid Nebula. Further, we find that V1735 Cygni is consistent in both position and proper motion with the streamer structure of IC 5146, and we trace the streamer's similar proper motions to the main cluster. Color-magnitude diagrams of all identified clusters show the presence of pre-main-sequence populations, strengthening the likelihood of a physical association between the young FU Ori stars and their respective nearby clusters.

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Tamojeet Roychowdhury, Lynne A. Hillenbrand. 2025-09-29. Seeking Kinematic Association of Known FU Orionis Stars with Young Clusters in Cygnus. https://arxiv.org/abs/2509.25341

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