Physics
Scientific paper
Jun 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005sptz.prop20499m&link_type=abstract
Spitzer Proposal ID #20499
Physics
Scientific paper
As the only galaxy for which we can obtain detailed information on the chemical, kinematical, and spatial distribution of large numbers of individual stars, the Milky Way (MW) is a primary laboratory for understanding the structure and evolution of spiral galaxies. However, we are denied clear views of stellar populations at low Galactic latitudes because of dust extinction. With Spitzer IRAC + 2MASS photometry we now have a powerful method to determine the line of sight reddening to any star, due to the fact that the longer bands in this combination sample the Rayleigh-Jeans part of the spectral energy distribution of stars, where all stars have essentially the same color. Thus, changes in NIR + mid-IR colors from reddening become immediately obvious and accurately measurable. We will use this technique to ``restore'' previously uninterpretable 2MASS color-magnitude diagrams (CMD) of fields along the Galactic plane and allow the first field star CMD studies of the MW in these regions. The Spitzer-targeted fields have been selected to address several perenniel and newly recognized problems in MW structure. We will: 1) Explore the recently discovered ``ring'' that appears to wrap around our disk in the 2nd and 3rd quadrants. 2) Test the claim of a new dwarf galaxy situated near this ring in Canis Major. 3) Probe a ``core'' overdensity of the ring -- perhaps the center of a dwarf galaxy creating the ring as a tidal tail -- hidden behind the dust. 4) Explore for the density, metallicity and kinematical distributions of stars in the MW disk to its edge. We will find the radius and shape of the disk and measure the rotation of the outer disk. 5) Check the Schlegel reddening maps across a wide range of dust conditions, and determine the three dimensional dust distribution for our survey regions. This study of IRAC+2MASS photometry through the veil of Galactic dust represents a major step forward in Galactic structure studies. These ``textbook'' measurements will be a true legacy from Spitzer.
Indebetouw Remy
Majewski Steven
Patterson Richard
Rocha-Pinto Helio
Skrutskie Michael
No associations
LandOfFree
Galactic Structure Through the Dusty Veil does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Galactic Structure Through the Dusty Veil, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galactic Structure Through the Dusty Veil will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1167308