Tag you’re it!

Title: Strong chemical tagging with APOGEE: 21 candidate star clusters that have dissolved across the Milky Way discAuthors: Natalie Price-Jones, Jo Bovy, Jeremy J. Webb, Carlos Allende Prieto, Rachael Beaton, Joel R. Brownstein, Roger E. Cohen, Katia Cunha, John Donor, Peter M. Frinchaboy, D. A. García-Hernández, Richard R. Lane, Steven R. Majewski, David L. Nidever, Alexandre Roman-LopesFirst Author’s Institution: David A. Dunlap Department of Astronomy and Astrophysics, University of Toronto, 50 St George Street, Toronto, ON M5S 3H4, CanadaStatus: Published in Monthly Notices of the Royal Astronomical Society, Volume 496, Issue 4, August 2020, Pages 5101–5115 [open access on arXiv] What is Chemical Tagging?Imagine, if you will, a pond. Imagine it’s filled with millions of different birds, fish, reptiles, and overall just a thriving ecosystem. If we were ornithologists focused on finding only the male mallard ducks, how would we do that? We could start with basic observations; if a creature is swimming in the pond, you’d probably be unconvinced that it’s a duck just by that. However, if it swam and walked around on the shore, that’s a slightly more convincing argument. If you hear it quacking at you for food (remember, frozen peas, not bread), you may be more firmly convinced it’s a duck. Finally, if it has a yellow bill, green head, and a gray-brown body, you can then be reasonably confident in your assumption that this creature is, in fact, a male mallard duck.Of course, this is an age-old adage, but its underlying principle is incredibly versatile! When trying to find a particular population (male mallard ducks) within a large sample, we can apply more...