@article{d97c563f9b9b48d5afb5d126235ead92,
title = "Mid-infrared images of luminous infrared galaxies in a merging sequence",
abstract = "We report mid-infrared observations of several luminous infrared galaxies (LIGs) carried out with the Infrared Space Observatory. Our sample was chosen to represent different phases of a merger sequence of galaxy-galaxy interaction with special emphasis on early/intermediate stages of merging. The mid-infrared emission of these LIGs shows extended structures for the early and intermediate mergers, indicating that most of the mid-infrared luminosities are not from a central active galactic nucleus. Both the infrared hardness (indicated by the IRAS 12, 25, and 60 μm flux density ratios) and the peak-to-total flux density ratios of these LIGs increase as projected separation of these interacting galaxies become smaller, consistent with increasing star formation activities that are concentrated to a smaller area as the merging process advances. These observations provide among the first observational constraint of largely theoretically based scenarios.",
keywords = "Galaxies: individual (Arp 302, NGC 6670, UGC 2369, NGC 7592, NGC 5256, Markarian 848, NGC 6090), Galaxies: interactions, Galaxies: starburst, Infrared: galaxies",
author = "Hwang, {Chorng Yuan} and Lo, {K. Y.} and Yu Gao and Gruendl, {Robert A.} and Lu, {Nanyao Y.}",
note = "Funding Information: The ISOCAM data presented in this Letter was analyzed using CAM Interactive Analysis, a joint development by the ESA Astrophysics Division and the ISOCAM Consortium led by the ISOCAM Principal Investigator, C. Cesarsky, Direction des Sciences de la Matiere, CEA, France. We thank K. Ganga and the ISO staff at IPAC for their help. K. Y. L. and R. A. G. were supported in part by NASA/ISO grant 961504, administered through the Jet Propulsion Laboratory of the California Institute of Technology. C.-Y. H. and K. Y. L. acknowledge support from the Academia Sinica and the National Science Council (grant 88-2112-M-001-020) of the Republic of China in Taiwan. Y. G., R. A. G., and K. Y. L. also acknowledge support from the Laboratory of Astronomical Imaging, which is funded by NSF grant AST 96-13999 and by the University of Illinois.",
year = "1999",
month = jan,
day = "20",
doi = "10.1086/311839",
language = "???core.languages.en_GB???",
volume = "511",
pages = "L17--L20",
journal = "Astrophysical Journal",
issn = "0004-637X",
number = "1 PART 2",
}