Sailing under the Magellanic Clouds: A DECam View of the Carina Dwarf

Abstract

We present deep optical photometry from the DECam imager on the 4m Blanco telescope of over 12 deg${}^2$ around the Carina dwarf spheroidal, with complete coverage out to 1 degree and partial coverage extending out to 2.6 degrees. Using a Poisson-based matched filter analysis to identify stars from each of the three main stellar populations, old, intermediate, and young, we confirm the previously identified radial age gradient, distance, tidal radius, stellar radial profiles, relative stellar population sizes, ellipticity, and position angle. We find an angular offset between the three main elliptical populations of Carina, and find only tentative evidence for tidal debris, suggesting that past tidal interactions could not have significantly influenced the Carina dwarf. We detect stars in the vicinity of, but distinct to, the Carina dwarf, and measure their distance to be 46$\pm$2 kpc. We determine this population to be part of the halo of the Large Magellanic Cloud at an angular radius of over 20 degrees. Due to overlap in colour-magnitude space with Magellanic stars, previously detected tidal features in the old population of Carina are likely weaker than previously thought.

13 pages, 10 figures, 2 tables

References in corpus (3)

• The Dartmouth Stellar Evolution Database
• Exploring Halo Substructure with Giant Stars XI: The Tidal Tails of the Carina Dwarf Spheroidal and the Discovery of Magellanic Cloud Stars in the Carina Foreground
• Life and times of dwarf spheroidal galaxies

Cited by in corpus (18)

• A fast radio burst in the direction of the Carina dwarf spheroidal galaxy
• Gaia early DR3 systemic motions of Local Group dwarf galaxies and orbital properties with a massive Large Magellanic Cloud
• Expanded haloes, abundance matching and too-big-to-fail in the Local Group
• The episodic Star Formation History of the Carina Dwarf Spheroidal Galaxy
• The Clouds are breaking: tracing the Magellanic system with Gaia DR1 Mira variables
• Stellar Substructures around the Hercules Dwarf Spheroidal Galaxy
• New mass bound on fermionic dark matter from a combined analysis of classical dSphs
• Tracing the stellar component of low surface brightness Milky Way Dwarf Galaxies to their outskirts I: Sextans
• Dissecting the stellar content of Leo I: a dwarf irregular caught in transition
• A low pre-infall mass for the Carina dwarf galaxy from disequilibrium modelling
• Extended stellar substructure surrounding the Boötes I dwarf spheroidal galaxy
• A MegaCam Survey of Outer Halo Satellites. VI: The Spatially Resolved Star Formation History of the Carina Dwarf Spheroidal Galaxy
• Gaia EDR3 proper motions of Milky Way dwarfs. II: Velocities, Total Energy and Angular Momentum
• An extended stellar halo discovered in the Fornax dwarf spheroidal using Gaia EDR3
• Young stars in the periphery of the Large Magellanic Cloud
• The radial acceleration relation at the EDGE of galaxy formation: testing its universality in low-mass dwarf galaxies
• Broken Expectations: The Effects of Modelling Assumptions on the Inferred Dark Matter Distribution in the Milky Way's Satellites
• The tidal features of the classical Milky Way satellites: Expected in MOND but inconsistent with cold dark matter models