2000/05/25 by M. Juvela, K. Mattila, Juvela, M. +3
Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Superconducting and THz Device Technology #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0005510
19 pages, 13 figures, to be published in the A&A Main Journal
arxiv created 2000/05/25 · openalex publication_date 2000/05/25 · arxiv updated 2009/12/01 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
As a part of the ISOPHOT CIRB (Cosmic Infrared Background Radiation) project\nwe have searched for point-like sources in eight fields mapped at two or three\nwavelengths between 90 and 180um. Most sources are previously unknown and based\non the far-infrared (FIR) spectral energy distributions dust-enshrouded,\ndistant galaxies form a significant fraction of the sources. We present a list\nof the new extragalactic FIR-sources and discuss the uncertainties of the\nsource detection from the ISOPHOT maps. We estimate the source number densities\nat 90, 150 and 180um and at flux density levels down to 100mJy to be 105, 2\n105, and 3 105 1/sr, respectively. Strong galaxy evolution models are in best\nagreement with our results, although the number of detections exceeds most\nmodel predictions. No-evolution models can be rejected at a high confidence\nlevel. Comparison with COBE results indicates that at 90um the detected sources\ncorrespond to some 20% of the extragalactic background light. At longer\nwavelengths the corresponding fraction is closer to 10%.\n