2002/09/27 by P. Temi, William G. Mathews, W. G. Mathews +7
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0209597
4 pages and 4 figures
arxiv created 2002/09/27 · openalex publication_date 2002/09/27 · arxiv updated 2009/12/01 · openalex created_date 2020/05/13 · openalex updated_date 2026/07/28
We present ISOPHOT P32 oversampled maps and P37/39 sparse maps, of three\nbright elliptical galaxies in the Virgo Cluster. The maps reach the limiting\nsensitivity of the ISOPHOT instrument at 60, 100, 170 and 200 microns. Two\nelliptical galaxies show no emission at all far-IR ISOPHOT wavelengths at a\nlevel of few tens of mJy. The null detection provides a test of the evolution\nof dust in elliptical galaxies and its size distribution and composition. As\nprevious studies have shown, in many elliptical galaxies both IRAS and ISO have\ndetected mid-IR excess 6-15 micron emission relative to the stellar continuum\nindicating emission from circumstellar dust. Under the assumption that these\ndusty outflows from evolving red giant stars and planetary nebulae are\ncontinuously supplying dust to the interstellar medium, we have computed the\ninfrared luminosity at the ISOPHOT bands appropriate for NGC4472. The null\nfar-IR ISOPHOT observations exceed the far-IR flux expected from dust expelled\nfrom a normal old stellar population.\n