The Dwarf Satellites of M31 and the Galaxy

Abstract

The satellite systems of M31 and the Galaxy are compared. It is noted that all five of the suspected stripped dSph cores of M31 companions are located within a projected distance of 40 kpc of from the nucleus of this galaxy, whereas the normal dSph companions to this object have distances > 40 kpc from the center of M31. All companions within 200 kpc < D(M31) < 600 kpc are late-type objects. The companions to the Galaxy appear to exhibit different systematics with the irregular LMC and SMC being located at small R_{gc}. It is speculated that this difference might be accounted for by assuming that the Magellanic Clouds are interlopers that were originally formed in the outer reaches of the Local Group. The radial distribution of the total sample of 40 companions of M31 and the Galaxy, which is shown in Figure 1, may hint at the possibility that these objects contain distinct populations of core (R < 25 kpc) and halo (R > 25 kpc) satellites.)

arXiv commentTo appear in the Astronomical Journal (October 2006)

References in corpus (19)

• A New Milky Way Dwarf Galaxy in Ursa Major
• The Progenitors of Dwarf Spheroidal Galaxies
• A New Milky Way Dwarf Satellite in Canes Venatici
• The properties of Galactic globular cluster sub-systems
• Mayall II = G1 in M31: Giant Globular Cluster or Core of a Dwarf Elliptical Galaxy ?
• Structural parameters for the M31 dwarf spheroidals
• A deep kinematic survey of planetary nebulae in the Andromeda Galaxy using the Planetary Nebula Spectrograph
• NGC 6791: an exotic open cluster or the nucleus of a tidally disrupted galaxy?
• A new population of extended, luminous star clusters in the halo of M31
• On the origin of cold dark matter halo density profiles
• The Anisotropic Distribution of M 31 Satellite Galaxies: A Polar Great Plane of Early-Type Companions
• The satellite distribution of M31
• Fossils of Reionization in the Local Group
• A New Giant Stellar Structure in the Outer Halo of M31
• The core of the Canis Major galaxy as traced by Red Clump stars
• Andromeda VIII - a New Tidally Distorted Satellite of M31
• On the Nature of Andromeda IV
• 037-B327 in M31: Luminous Globular Cluster or Core of a Former Dwarf Spheroidal Companion to M31?
• The Proper Motion of the Large Magellanic Cloud: A Reanalysis

Cited by in corpus (22)

• Are the Magellanic Clouds on their First Passage about the Milky Way?
• Third-Epoch Magellanic Cloud Proper Motions I: HST/WFC3 data and Orbit Implications
• Dark matter substructure and gamma-ray annihilation in the Milky Way halo
• HI in Local Group Dwarf Galaxies and Stripping by the Galactic Halo
• The Role of Dwarf Galaxy Interactions in Shaping the Magellanic System and Implications for Magellanic Irregulars
• Discovery of New Dwarf Galaxies in the M81 Group
• TiNy Titans: The Role of Dwarf-Dwarf Interactions in the Evolution of Low Mass Galaxies
• Orbits of Massive Satellite Galaxies: I. A Close Look at the Large Magellanic Cloud and a New Orbital History for M33
• The vast thin plane of M31 co-rotating dwarfs: an additional fossil signature of the M31 merger and of its considerable impact in the whole Local Group
• Dynamics of the Magellanic Clouds in a LCDM Universe
• The Magellanic Stream System: I. Ram-pressure tails and the relics of the collision between the Magellanic Clouds
• Origin and Evolution of the Abundance Gradient along the Milky Way Disk
• The Frequency of Dwarf Galaxy Multiples at Low Redshift in SDSS vs. Cosmological Expectations
• Proper Motion Study of the Magellanic Clouds using SPM material
• Dwarf Galaxies in the NGC 1023 Group
• Could the Magellanic Clouds be tidal dwarves expelled from a past-merger event occurring in Andromeda?
• Carbon and nitrogen abundances of individual stars in the Sculptor dwarf spheroidal galaxy
• Kinematical Structure of the Magellanic System
• Revisiting the Role of M31 in the Dynamical History of the Magellanic Clouds
• Searching for Milky Way twins: Radial abundance distribution as a strict criterion
• Local Group Proper Motion Dynamics
• The orbital dynamics of the LMC and SMC about the Milky Way