Structure of the SMC - Stellar component distribution from 2MASS data

Abstract

The spatial distribution of the SMC stellar component is investigated from 2MASS data. The morphology of the different age populations is presented. The center of the distribution is calculated and compared with previous estimations. The rotation of the stellar content and possible consequence of dark matter presence are discussed. The different stellar populations are identified through a CMD diagram of the 2MASS data. Isopleth contour maps are produced in every case, to reveal the spatial distribution. The derived density profiles are discussed. The older stellar population follows an exponential profile at projected diameters of about 5 kpc (~5 deg) for the major axis and ~4 kpc for the minor axis, centred at RA: 0h:51min, Dec: -73deg 7' (J2000.0). The centre coordinates are found the same for all the different age population maps and are in good accordance with the kinematical centre of the SMC. However they are found considerably different from the coordinates of the centre of the gas distribution. The fact that the older population found on an exponential disk, gives evidence that the stellar content is rotating, with a possible consequence of dark matter presence. The strong interactions between the MCs and the MilkyWay might explain the difference in the distributions of the stellar and gas components. The lack in the observed velocity element, that implies absence of rotation, and contradicts with the consequences of exponential profile of the stellar component, may also be a result of the gravitational interactions.

7 Pages, 6 figures, accepted for publication in A&A

References in corpus (3)

• A New Look at the Kinematics of Neutral Hydrogen in the Small Magellanic Cloud
• The Most Dark Matter Dominated Galaxies: Predicted Gamma-ray Signals from the Faintest Milky Way Dwarfs
• Gas distribution, kinematics and star formation in faint dwarf galaxies

Cited by in corpus (28)

• The VMC Survey - I. Strategy and First Data
• A distance determination to the Small Magellanic Cloud with an accuracy of better than 2 percent based on late-type eclipsing binary stars
• New Optical Reddening Maps of the Large and Small Magellanic Clouds
• The metallicity gradient as a tracer of history and structure: the Magellanic Clouds and M33 galaxies
• The VMC Survey - XIV. First results on the look-back time star-formation rate tomography of the Small Magellanic Cloud
• The VMC Survey. XXV. The 3D structure of the Small Magellanic Cloud from Classical Cepheids
• Three dimensional maps of the Magellanic Clouds using RR Lyrae Stars and Cepheids II. The Small Magellanic Cloud
• Detection of the Small Magellanic Cloud in gamma-rays with Fermi/LAT
• Mean age gradient and asymmetry in the star formation history of the Small Magellanic Cloud
• Revealing the tidal scars of the Small Magellanic Cloud
• Microlensing towards the SMC: a new analysis of OGLE and EROS results
• The VMC Survey -- XXXIV. Morphology of Stellar Populations in the Magellanic Clouds
• Metallicity distribution functions of the old populations of the Magellanic Clouds from RR Lyrae stars
• High-energy gamma-ray and neutrino production in star-forming galaxies across cosmic time: Difficulties in explaining the IceCube data
• The VMC Survey -- XL. Three-dimensional structure of the Small Magellanic Cloud as derived from red clump stars
• The shapes of Milky Way satellites: looking for signatures of tidal stirring
• RR Lyrae variables in the Small Magellanic Cloud - II. The extended area: chemical and structural analysis
• STEP Survey II: Structural Analysis of 170 star clusters in the SMC
• Chemical abundances of metal-poor RR Lyrae stars in the Magellanic Clouds
• Microlensing optical depth, event rate, and limits on compact objects in dark matter based on 20 yr of OGLE observations of the Small Magellanic Cloud
• Role of galactic bars in the formation of spiral arms: A study through orbital and escape dynamics -- I
• New limits on the population of normal and millisecond pulsars in the Large and Small Magellanic Clouds
• UVIT Study of the MAgellanic Clouds (U-SMAC) II. A Far-UV catalog of the Small Magellanic Cloud: Morphology and Kinematics of young stellar population
• Spatial distribution of stellar populations in the Magellanic Clouds: Implementation to Gaia
• Prospects of newly detecting nearby star-forming galaxies by the Cherenkov Telescope Array
• A Galactic Transformation -- Understanding the SMC's Structural and Kinematic Disequilibrium
• The diffuse extragalactic gamma-ray background radiation: star-forming galaxies are not the dominant component
• The orbital dynamics of the LMC and SMC about the Milky Way