1999/06/30 by B. T. Soifer, K. Matthews, G. Neugebauer +6 · 41 citations
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Emission spectrum #Extinction (optical mineralogy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Infrared #Line (geometry) #Observatory #Optics #Physics #Redshift #Spectral line #Spectroscopy #Star formation #Stellar, planetary, and galactic studies #Telescope #astro-ph
paper · pdf · doi:10.1086/301071
published in The Astronomical Journal 118(5), 2065-2070 (Institute of Physics) · Latex with AAS format, 3 postscript figures, AJ, accepted, includes new I data, new fig 3 and revised interpretation
arxiv created 1999/08/14 · openalex publication_date 1999/11/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Near-infrared imaging and spectroscopic observations of the extremely red object Cl 0939+4713B ( R - K ∼ 7 mag) have been obtained with the Near Infrared Camera on the Keck I Telescope of the W. M. Keck Observatory. The imaging shows a slightly elongated structure, while the spectroscopy shows a continuum break that allows us to determine a redshift of z = 1.58 for this system. The fits of a range of models to the infrared spectrum suggest that it is predominantly an old (>10 9 yr) stellar system that suffers little extinction, while the measured R and I magnitudes suggest an age of ∼3 × 10 8 yr. The limit on the equivalent width of any emission line in the infrared spectrum suggests that Cl 0939+4713B is not an actively star-forming galaxy. This system, though similar in R - K color to the object HR 10 (also known as J1645+46), is much different in morphology and emission-line strengths, demonstrating the heterogeneity of extremely red extragalactic objects selected on the basis of large R - K values.