AEGIS: Infrared Spectroscopy of an Infrared-luminous Lyman Break Galaxy at z = 3.01 Academic Article uri icon


  • We report the detection of rest-frame 6.2 and 7.7 m emission features arising from polycyclic aromatic hydrocarbons (PAHs) in the Spitzer IRS spectrum of an infrared-luminous Lyman break galaxy at z = 3.01. This is currently the highest redshift galaxy where these PAH emission features have been detected. The total IR luminosity inferred from the MIPS 24 m and radio flux density is 2 1013 L, which qualifies this object as a so-called hyperluminous infrared galaxy (HyLIRG). However, unlike local HyLIRGs, which are generally associated with QSO/AGNs and have weak or absent PAH emission features, this HyLIRG has very strong 6.2 and 7.7 m PAH emission. We argue that intense star formation dominates the IR emission of this source, although we cannot rule out the presence of a deeply obscured AGN. This LBG appears to be a distorted system in the HST ACS F606W and F814W images, possibly indicating that a significant merger or interaction is driving the large IR luminosity. 2007. The American Astronomical Society. All rights reserved.

published proceedings

  • The Astrophysical Journal

author list (cited authors)

  • Huang, J., Rigopoulou, D., Papovich, C., Ashby, M., Willner, S. P., Ivison, R., ... Fazio, G. G.

citation count

  • 21

complete list of authors

  • Huang, J-S||Rigopoulou, D||Papovich, C||Ashby, MLN||Willner, SP||Ivison, R||Laird, ES||Webb, T||Wilson, G||Barmby, P||Chapman, S||Conselice, C||McLeod, B||Shu, CG||Smith, HA||Le Floc’h, E||Egami, E||Willmer, CAN||Fazio, GG

publication date

  • September 2006