Deeply Buried Nuclei in the Infrared-luminous Galaxies NGC 4418 and Arp 220. I. ALMA Observations at λ = 1.4–0.4 mm and Continuum Analysis

  title={Deeply Buried Nuclei in the Infrared-luminous Galaxies NGC 4418 and Arp 220. I. ALMA Observations at $\lambda$ = 1.4–0.4 mm and Continuum Analysis},
  author={Kazushi Sakamoto and Eduardo Gonz{\'a}lez-Alfonso and Sergio Mart{\'i}n and David J. Wilner and Susanne Aalto and Aaron S. Evans and Nanase Harada},
  journal={The Astrophysical Journal},
We observed with Atacama Large Millimeter/submillimeter Array three deeply buried nuclei in two galaxies, NGC 4418 and Arp 220, at ∼0.″2 resolution over a total bandwidth of 67 GHz in f rest = 215–697 GHz. Here we (1) introduce our program, (2) describe our data reduction method for wide-band, high-resolution imaging spectroscopy, (3) analyze in visibilities the compact nuclei with line forests, (4) develop a continuum-based estimation method of dust opacity and gas column density in heavily… 
Deeply Buried Nuclei in the Infrared-luminous Galaxies NGC 4418 and Arp 220. II. Line Forests at λ = 1.4–0.4 mm and Circumnuclear Gas Observed with ALMA
We present the line observations in our Atacama Millimeter-Submillimeter Array imaging spectral scan toward three deeply buried nuclei in NGC 4418 and Arp 220. We cover 67 GHz in f rest = 215–697 GHz


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