Hidden depths in the local Universe: The Stellar Stream Legacy Survey
Abstract
Mergers and tidal interactions between massive galaxies and their dwarf satellites are a fundamental prediction of the Lambda-Cold Dark Matter cosmology. These events are thought to provide important observational diagnostics of nonlinear structure formation. Stellar streams in the Milky Way and Andromeda are spectacular evidence for ongoing satellite disruption. However, constructing a statistically meaningful sample of tidal streams beyond the Local Group has proven a daunting observational challenge, and the full potential for deepening our understanding of galaxy assembly using stellar streams has yet to be realised. Here we introduce the Stellar Stream Legacy Survey, a systematic imaging survey of tidal features associated with dwarf galaxy accretion around a sample of ~3100 nearby galaxies within z~0.02, including about 940 Milky Way analogues. Our survey exploits public deep imaging data from the DESI Legacy Imaging Surveys, which reach surface brightness as faint as ~29 mag/arcsec^2 in the r band. As a proof of concept of our survey, we report the detection and broad-band photometry of 24 new stellar streams in the local Universe. We discuss how these observations can yield new constraints on galaxy formation theory through comparison to mock observations from cosmological galaxy simulations. These tests will probe the present-day mass assembly rate of galaxies, the stellar populations and orbits of satellites, the growth of stellar halos and the resilience of stellar disks to satellite bombardment.
Keywords
Cite
@article{arxiv.2104.06071,
title = {Hidden depths in the local Universe: The Stellar Stream Legacy Survey},
author = {David Martinez-Delgado and Andrew P. Cooper and Javier Roman and Annalisa Pillepich and Denis Erkal and Sarah Pearson and John Moustakas and Chervin F. P. Laporte and Seppo Laine and Mohammad Akhlaghi and Dustin Lang and Dmitry Makarov and Alejandro S. Borlaff and Giuseppe Donatiello and William J. Pearson and Juan Miro-Carretero and Jean-Charles Cuillandre and Helena Dominguez and Santi Roca-Fabrega and Carlos S. Frenk and Judy Schmidt and Maria A. Gomez-Flechoso and Rafael Guzman and Noam I. Libeskind and Arjun Dey and Benjamin A. Weaver and David Schlegel and Adam D. Myers and Frank G. Valdes},
journal= {arXiv preprint arXiv:2104.06071},
year = {2023}
}
Comments
Accepted in Astronomy & Astrophysics, 25 pages, 17 figures, 3 tables