Deep Near-Infrared Imaging of a Field in the Outer Disk of M82 with the ALTAIR Adaptive Optics System on Gemini North
arXiv:astro-ph/0312278 · doi:10.1086/380850
Abstract
Deep H and K' images, recorded with the ALTAIR adaptive optics system and NIRI imager on Gemini North, are used to probe the red stellar content in a field with a projected distance of 1 kpc above the disk plane of the starburst galaxy M82. The data have an angular resolution of 0.08 arcsec FWHM, and individual AGB and RGB stars are resolved. The AGB extends to at least 1.7 mag in K above the RGB-tip, which occurs at K = 21.7. The relative numbers of bright AGB stars and RGB stars are consistent with stellar evolution models, and one of the brightest AGB stars has an H-K color and K brightness that is consistent with it being a C star. The brightnesses of the AGB stars suggest that they formed during intermediate epochs, possibily after the last major interaction with M81. Therefore, star formation in M82 during intermediate epochs may not have been restricted to the plane of the disk.
arXiv comment16 pages of text plus 7 postscript figures; to appear in the PASP
References in corpus (28)
- Evolutionary tracks and isochrones for low- and intermediate-mass stars: from 0.15 to 7 M_sun, and from Z=0.0004 to 0.03
- Theoretical isochrones in several photometric systems I. Johnson-Cousins-Glass, HST/WFPC2, HST/NICMOS, Washington, and ESO Imaging Survey filter sets
- The Metamorphosis of Tidally Stirred Dwarf Galaxies
- The Impact of Star Formation on the Interstellar Medium in Dwarf Galaxies: II. The Formation of Galactic Winds
- The Asymmetric Wind in M82
- Evolutionary synthesis of stellar populations: a modular tool
- Discovery of Recent Star Formation in the Extreme Outer Regions of Disk Galaxies
- A Structural and Dynamical Study of Late-Type, Edge-On Galaxies: II. Vertical Color Gradients and the Detection of Ubiquitous Thick Disks
- A new IR-Array photometric survey of Galactic Globular Clusters: A detailed study of the RGB sequence as a step towards the global testing of stellar models
- M82-F: A Doomed Super Star Cluster?
- The Fossil Starburst in M82
- Using the Ca II Triplet to Trace Abundance Variations in Individual Red Giant Branch stars in Three Nearby Galaxies
- Detection of the Red Giant Branch Stars in M82 Using the Hubble Space Telescope
- A blind HI survey of the M81 group
- The Interacting Dwarf Galaxy NGC 3077: The Interplay of Atomic and Molecular Gas with Violent Star Formation
- An Upper Limit to the Age of the Galactic Bar
- Star Cluster Formation and Disruption Time-Scales - II. Evolution of the Star Cluster System in M82's Fossil Starburst
- Stellar Populations and Ages of M82 Super Star Clusters
- The Star Formation History of NGC 6822
- The Outer Regions of the Nearby Sc Galaxies NGC 2403 and M33: Evidence for an Intermediate Age Population at Large Radii
- Constraints on Galaxy Formation from Stars in the Far Outer Disk of M31
- The Asymptotic Giant Branch of NGC 205: The Characteristics of Carbon Stars and M Giants Identified from JHK' Images
- Chandra Observations of Expanding Shells in the Dwarf Starburst Galaxy NGC 3077
- Young Stars in the Outer HI Disc of NGC 6822
- Discovery of Molecular Gas in the Outflow and Tidal Arms around M82
- The Metallicity of the Red Giant Branch in the Disk of NGC 6822
- Near-Infrared Imaging of the Central Regions of Metal-Poor Inner Spheroid Globular Clusters
- Chemical evolution of the M82 B fossil starburst