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AKARI Infrared Camera (IRC) Imaging Observations: Highlights Yoshifusa ITA1) and AKARI/IRC team 1) National Institutes of Natural Sciences, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588, Japan [email protected] The Infrared Camera (IRC; Onaka et al 2007) is one of the two main instruments on board the AKARI (formerly ASTRO-F; Murakami et al. 2007) satellite. The IRC is comprised of three independent arrays; NIR, MIRS, and MIRL, which cover the 1.8–5.5um, 4.6–13.4um, and 12.6–26.5 um wavelength range, respectively. Each of the three arrays has three imaging filters, which can be switched during the observation. Each of the arrays has a wide field of view of about 10’x10’, suitable for survey-type observations. Here we present some highlights of the IRC imaging observations made so far, to demonstrate the ability of the IRC and its performance. 1. Supernova remnant in the Small Magellanic Cloud: B0104-72.3, a well-known supernova remnant in the SMC was imaged by the IRC at four different infrared wavelengths. The intensity ratios of them revealed the presence of a shock at the interaction between the expanding remnant and the surrounding molecular clouds. This implies that the precursor was a high-mass star (Koo et al 2007). 2. Mass-loss from young red-giants in a globular cluster NGC 104: A globular cluster, NGC104 was imaged by the IRC at 3, 4, 7, 11, 15, and 24 micrometers. The intensity ratio vs. K magnitude diagram showed evidence of mass-loss from young red-giant stars. The mass loss in the early red-giant phase, important for understanding the evolution of galaxies, had been predicted only in theory so far. (Ita et al 2007) 3. Intense star formation activity in the early Universe: North Ecliptic Pole region was deeply imaged by the IRC, resulting in the detection of around 280 galaxies, confirming the increase in the number of galaxies at 15 micrometers implied by the earlier ISO observations. Comparable numbers of even fainter galaxies have been discovered, leading to the conclusion that the star formation activity was already intense even earlier than 6 thousand million years in the past. Similar deep surveys over the entire IRC wavelength range are being carried out. These data will provide a definitive description of the evolution of galaxies over the lifetime of the Universe (Matsuhara et al. 2007; Wada et al 2007). 4. Near- and mid-infrared view of the Large Magellanic Cloud: About 13 square degrees of the main part of the LMC are surveyed by the IRC. The data will enable us to study the way stars recycle their constituent gases and return them to the interstellar medium at the end of their lives. 5. More to come!! This paper is a mere summary of the web pages, http://www.ir.isas.jaxa.jp/ASTRO-F/Outreach/results/results_e.html and http://akari.esac.esa.int/ . Please visit the urls if you are interested. References Ita, Y., et al. 2007, PASJ, 59, 437 Koo, B.-C., et al. 2007, PASJ, 59, 455 Matsuhara, H., et al. 2007, PASJ, 59, 543 Murakami, H., et al. 2007, PASJ, 59, 369 Onaka, T., et al. 2007, PASJ, 59, 401 Wada, T., et al. 2007, PASJ, 59, 515