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تسجيل مستخدم جديدDistorted HI Gas in the Widely Separated LIRG Arp 256
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Jacqueline Chen
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We present new interferometric HI and CO (1-0) observations of the luminous infrared source, Arp 256. Arp 256 consists of two spiral galaxies in an early stage of merging, with a projected nuclear separation of 29 kpc (54) and an infrared luminosity of 2.0E11 L_sun. Despite the large separation of the galaxies nuclei and mildly disrupted stellar components, the HI disks are found to be strongly disrupted, and the southern galaxy in Arp 256 shows an elevated star formation efficiency, which is consistent with a nuclear starburst. Both of these results run contrary to expectations, posing interesting questions on the physical mechanisms involved in stimulating star formation during an interaction.
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