High-resolution near-infrared imaging of submillimeter galaxies

Paula Aguirre, Andrew J. Baker, Felipe Menanteau, Dieter Lutz, Linda J. Tacconi

Research output: Contribution to journalArticlepeer-review


We present F110W (∼J) and F160W (∼H) observations of 10 submillimeter galaxies (SMGs) obtained with the Hubble Space Telescope's (HST's) NICMOS camera. Our targets have optical redshifts in the range 2.20 ≤ z ≤ 2.81 confirmed by millimeter CO or mid-IR spectroscopy, guaranteeing that the two bands sample the rest-frame optical with the Balmer break falling between them. Eight of ten are detected in both bands, while two are detected in F160W only. We study their F160W morphologies, applying a maximum-deblending detection algorithm to distinguish multiple- from single-component configurations, leading to reassessments for several objects. Based on our NICMOS imaging and/or previous dynamical evidence we identify five SMGs as multiple sources, which we interpret as merging systems. Additionally, we calculate morphological parameter asymmetry (A) and the Gini coefficient (G); thanks to our sample's limited redshift range we recover the trend that multiple-component, merger-like morphologies are reflected in higher asymmetries. We analyze the stellar populations of nine objects with F110W/F160W photometry, using archival HST optical data when available. For multiple systems, we are able to model the individual components that build up an SMG. With the available data we cannot discriminate among star formation histories, but we constrain stellar masses and mass ratios for merger-like SMG systems, obtaining a mean log (M*/M ) = 10.9 ± 0.2 for our full sample, with individual values log (M*/M) ∼ 9.6-11.8. The morphologies and mass ratios of the least and most massive systems match the predictions of the major-merger and cold accretion SMG formation scenarios, respectively, suggesting that both channels may have a role in the population's origin.

Original languageEnglish (US)
Article number164
JournalAstrophysical Journal
Issue number2
StatePublished - May 10 2013
Externally publishedYes


  • galaxies: high-redshift
  • galaxies: interactions
  • galaxies: stellar content
  • galaxies: structure

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'High-resolution near-infrared imaging of submillimeter galaxies'. Together they form a unique fingerprint.

Cite this