Candidate Distant Trans-Neptunian Objects Detected by the New Horizons Subaru TNO Survey

Wesley C. Fraser; Simon B. Porter; Lowell Peltier; JJ Kavelaars; Anne J. Verbiscer; Marc W. Buie; S. Alan Stern; John R. Spencer; Susan D. Benecchi; Tsuyoshi Terai; Takashi Ito; Fumi Yoshida; David W. Gerdes; Kevin J. Napier; Hsing Wen Lin; Stephen D. J. Gwyn; Hayden Smotherman; Sebastien Fabbro; Kelsi N. Singer; Amanda M. Alexander; Ko Arimatsu; Maria E. Banks; Veronica J. Bray; Mohamed Ramy El-Maarry; Chelsea L. Ferrell; Tetsuharu Fuse; Florian Glass; Timothy R. Holt; Peng Hong; Ryo Ishimaru; Perianne E. Johnson; Tod R. Lauer; Rodrigo Leiva; Patryk S. Lykawka; Raphael Marschall; Jorge I. Núñez; Marc Postman; Eric Quirico; Alyssa R. Rhoden; Anna M. Simpson; Paul Schenk; Michael F. Skrutskie; Andrew J. Steffl; Henry Throop

arXiv · 2407.21142

Candidate Distant Trans-Neptunian Objects Detected by the New Horizons Subaru TNO Survey

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Abstract

We report the detection of 239 trans-Neptunian Objects discovered through the on-going New Horizons survey for distant minor bodies being performed with the Hyper Suprime-Cam mosaic imager on the Subaru Telescope. These objects were discovered in images acquired with either the r2 or the recently commissioned EB-gri filter using shift and stack routines. Due to the extremely high stellar density of the search region down stream of the spacecraft, new machine learning techniques had to be developed to manage the extremely high false positive rate of bogus candidates produced from the shift and stack routines. We report discoveries as faint as r2$\sim26.5$. We highlight an overabundance of objects found at heliocentric distances $R\gtrsim70$~au compared to expectations from modelling of the known outer Solar System. If confirmed, these objects betray the presence of a heretofore unrecognized abundance of distant objects that can help explain a number of other observations that otherwise remain at odds with the known Kuiper Belt, including detections of serendipitous stellar occultations, and recent results from the Student Dust Counter on-board the New Horizons spacecraft.

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Wesley C. Fraser, Simon B. Porter, Lowell Peltier, JJ Kavelaars, Anne J. Verbiscer, Marc W. Buie, S. Alan Stern, John R. Spencer, Susan D. Benecchi, Tsuyoshi Terai, Takashi Ito, Fumi Yoshida, David W. Gerdes, Kevin J. Napier, Hsing Wen Lin, Stephen D. J. Gwyn, Hayden Smotherman, Sebastien Fabbro, Kelsi N. Singer, Amanda M. Alexander, Ko Arimatsu, Maria E. Banks, Veronica J. Bray, Mohamed Ramy El-Maarry, Chelsea L. Ferrell, Tetsuharu Fuse, Florian Glass, Timothy R. Holt, Peng Hong, Ryo Ishimaru, Perianne E. Johnson, Tod R. Lauer, Rodrigo Leiva, Patryk S. Lykawka, Raphael Marschall, Jorge I. Núñez, Marc Postman, Eric Quirico, Alyssa R. Rhoden, Anna M. Simpson, Paul Schenk, Michael F. Skrutskie, Andrew J. Steffl, Henry Throop. 2024-07-30. Candidate Distant Trans-Neptunian Objects Detected by the New Horizons Subaru TNO Survey. https://arxiv.org/abs/2407.21142

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