English

An Evolutionary Model For Submillimeter Galaxies

Astrophysics 2009-11-11 v1

Abstract

[abridged]We calculate multi-wavelength spectral energy distributions (SEDs) (spanning optical to millimeter wavelengths) from simulations of major galaxy mergers with black hole feedback which produce submillimeter bright galaxies (SMGs), using a self-consistent three-dimensional radiative transfer code. We reproduce correlations for local AGN observed in Spitzer Space Telescope's IRAC bands, and make definitive predictions for infrared X-ray correlations that should be testable by combining observations by Spitzer and the upcoming Herschel mission with X-ray surveys. Our dynamical approach allows us to directly correlate observed clustering in the data as seen in IRAC color-color plots with the relative amount of time the system spends in a region of color-color space. We also find that this clustering is positively correlated with the stars dominating in their contribution to the total bolometric luminosity. We present photo albums spanning the lifetime of SMGs, from their infancy in the pre-merger phase to the final stage as an elliptical galaxy, as seen in the observed 3.6\micron3.6 \micron and 450\micron450 \micron band to visually illustrate some of the morphological differences between mergers of differing orbital inclination and progenitor redshift. We find that SMGs are a broader class of systems than starbursts or quasars. We introduce a simple, heuristic classification scheme on the basis of the LIR/LxL_{\rm IR}/L_{\rm x} ratios of these galaxies, which may be interpreted qualitatively as an evolutionary scheme, as these galaxies evolve in LIR/LxL_{\rm IR}/L_{\rm x} while transiting from the pre-merger stage, through the quasar phase, to a merger remnant.

Keywords

Cite

@article{arxiv.astro-ph/0610860,
  title  = {An Evolutionary Model For Submillimeter Galaxies},
  author = {Sukanya Chakrabarti and Yeshe Fenner and Lars Hernquist and T. J. Cox and Philip F. Hopkins},
  journal= {arXiv preprint arXiv:astro-ph/0610860},
  year   = {2009}
}

Comments

19 pages, 27 figures, Submitted to ApJ, higher resolution figures can be found at http://www.cfa.harvard.edu/~schakrab/smg.ps