Stellar disc streams as probes of the Galactic potential and satellite impacts

Abstract

Stars aligned in thin stream-like features (feathers), with widths of $\delta \sim 1-10^{\circ }$ and lengths as large as $\Delta l\sim 180^{\circ }$, have been observed towards the Anticenter of our Galaxy and their properties mapped in abundances and phase-space. We study their origin by analysing similar features arising in an N-body simulation of a Galactic disc interacting with a Sagittarius-like dwarf spheroidal galaxy (Sgr). By following the orbits of the particles identified as contributing to feathers backwards in time, we trace their excitation to one of Sgr's previous pericentric passages. These particles initially span a large range of phase-angles but a tight range of radii, suggesting they provide a probe of populations in distinct annuli in the outer Galactic disc. The structures are long lived and persist after multiple passages on timescales of $\sim 4\mathrm{Gyrs}$. On the sky, they exhibit oscillatory motion that can be traced with a single orbit mapped over much of their full length and with amplitudes and gradients similar to those observed. We demonstrate how these properties of feathers may be exploited to measure the potential, its flattening, as well as infer the strength of recent potential perturbations.

arXiv comment10 pages, 10 figures, submitted to MNRAS, comments welcome

References in corpus (47)

• The NumPy array: a structure for efficient numerical computation
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• Tracing Galaxy Formation with Stellar Halos I: Methods
• The Field of Streams: Sagittarius and its Siblings
• Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
• The Ghost of Sagittarius and Lumps in the Halo of the Milky Way
• Chemical Cartography with APOGEE: Metallicity Distribution Functions and the Chemical Structure of the Milky Way Disk
• Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program.Galactic stellar populations and planets
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• Beasts of the Southern Wild: Discovery of nine Ultra Faint satellites in the vicinity of the Magellanic Clouds
• The age structure of stellar populations in the solar vicinity. Clues of a two-phase formation history of the Milky Way disk
• Gaia broad band photometry
• A Faint New Milky Way Satellite in Bootes
• The accretion origin of the Milky Way's stellar halo
• Tracing Galaxy Formation with Stellar Halos II: Relating Substructure in Phase- and Abundance-Space to Accretion Histories
• Cold Dark Matter Substructure and Galactic Disks I: Morphological Signatures of Hierarchical Satellite Accretion
• The local density of matter mapped by Hipparcos
• Galactoseismology: Discovery of Vertical Waves in the Galactic Disk
• Thin, thick and dark discs in LCDM
• One Ring to Encompass them All: A giant stellar structure that surrounds the Galaxy
• The Sagittarius impact as an architect of spirality and outer rings in the Milky Way
• Sagittarius II, Draco II and Laevens 3: three new Milky Way satellites discovered in the Pan-STARRS 1 3pi Survey
• Vertical density waves in the Milky Way disc induced by the Sagittarius Dwarf Galaxy
• Gaia reveals a metal-rich in-situ component of the local stellar halo
• Exploring Halo Substructure with Giant Stars: A diffuse star cloud or tidal debris around the Milky Way in Triangulum-Andromeda
• Substructure in Tidal Streams; Tributaries in the Anticenter Ring
• Response of the Milky Way's disc to the Large Magellanic Cloud in a first infall scenario
• Warp, Waves, and Wrinkles in the Milky Way
• A Synoptic Map of Halo Substructures from the Pan-STARRS1 3π Survey
• On the kinematic detection of accreted streams in the Gaia era: a cautionary tale
• Detection of the Main Sequence Turn-off of a Newly Discovered Milky Way Halo Structure in the Triangulum-Andromeda Region
• A re-interpretation of the Triangulum-Andromeda stellar clouds: a population of halo stars kicked out of the Galactic disk
• A Cold Milky Way Stellar Stream in the Direction of Triangulum
• A fully cosmological model of a Monoceros-like ring
• Red clump stars and Gaia: Calibration of the standard candle using a hierarchical probabilistic model
• Two chemically similar stellar overdensities on opposite sides of the plane of the Galaxy
• Galactic halo stellar structures in the Triangulum-Andromeda region
• The Complex Structure of Stars in the Outer Galactic Disk as revealed by Pan-STARRS1
• Is the Milky Way still breathing? RAVE-Gaia streaming motions
• Group finding in the stellar halo using M-giants in 2MASS: An extended view of the Pisces Overdensity?
• TriAnd and its Siblings: Satellites of Satellites in the Milky Way Halo
• Exploring Halo Substructure with Giant Stars: The Nature of the Triangulum-Andromeda Stellar Features
• The fall of the Northern Unicorn: Tangential motions in the Galactic Anti-centre with SDSS and Gaia
• A Disk Origin for the Monoceros Ring and A13 Stellar Overdensities
• Another Look at the EBS: A Stellar Debris Stream and a Possible Progenitor
• Cresting the wave: Proper motions of the Eastern Banded Structure
• The vertical force in the Solar Neighbourhood using red clump stars in TGASxRAVE - Constraints on the local dark matter density

Cited by in corpus (24)

• Footprints of the Sagittarius dwarf galaxy in the $Gaia$ data set
• The Spur and the Gap in GD-1: Dynamical evidence for a dark substructure in the Milky Way halo
• The mass of our Milky Way
• galstreams: A Library of Milky Way Stellar Stream Footprints and Tracks
• Gaia Early Data Release 3: The Galactic anticentre
• Stellar migrations and metal flows -- Chemical evolution of the thin disc of a simulated Milky Way analogous galaxy
• Hidden depths in the local Universe: The Stellar Stream Legacy Survey
• Gaia Data Release 3: Chemical cartography of the Milky Way
• Evidence for the Third Stellar Population in the Milky Way's Disk
• Chemo-dynamical properties of the Anticenter Stream: a surviving disc fossil from a past satellite interaction
• Beyond the two-infall model I. Indications for a recent gas infall with Gaia DR3 chemical abundances
• The Galaxy Progenitors of Stellar Streams around Milky Way-mass Galaxies in the FIRE Cosmological Simulations
• Is NGC 5824 the Core of the Progenitor of the Cetus Stream?
• Measuring the vertical response of the Galactic disc to an infalling satellite
• A-type stars in the Canada-France Imaging Survey II. Tracing the height of the disc at large distances with Blue Stragglers
• The nature of the Milky Way's stellar halo revealed by the three integrals of motion
• The outer disc in shambles: blind detection of Monoceros and ACS with Gaia's astrometric sample
• Kinematics beats dust: unveiling nested substructure in the perturbed outer disc of the Milky Way
• 2D chemical evolution models II. Effects of multiple spiral arm patterns on O, Eu, Fe and Ba abundance gradients
• The Implications of Local Fluctuations in the Galactic Midplane for Dynamical Analysis in the Gaia Era
• Shaping the Milky Way: The interplay of mergers and cosmic filaments
• A chemical close-up of the main body of the Sagittarius dwarf galaxy
• Low-density star cluster formation: discovery of a young faint fuzzy on the outskirts of the low-mass spiral galaxy NGC 247
• Stellar streams around dwarf galaxies in the Local Universe