Testing the Robustness of Via Machinae Stellar Stream Candidates

16 Jul 2025, 10:00
25m

Speaker

Rafael Porto

Description

We build upon the results of the Via Machinae algorithm for stellar stream-finding in Gaia data, employing new tests to identify the stream candidates most likely to represent real stellar streams. We measure the consistency with which candidates are discovered across multiple retrainings of the Via Machinae neural density estimators, and we find that classifying candidates based on this metric reduces the expected rate of false positive discoveries by a factor of roughly 2 while increasing the number of stream candidates classified as real by more than 20%. As an independent test, we apply an automated orbit-fitting algorithm to determine whether each candidate lies along a physical orbit integrated in a model of the Milky Way gravitational potential. We present a list of candidates that pass both these tests and merit follow-up observations, some of which are to our knowledge previously unknown.

Authors

David Shih Rafael Porto

Presentation materials