ULTRA-COMPACT DWARFS IN THE FOSSIL GROUP NGC 1132
نویسندگان
چکیده
منابع مشابه
Galaxy Threshing and Ultra-Compact Dwarfs in the Fornax Cluster
We have discovered a new type of galaxy in the Fornax Cluster: “ultracompact” dwarfs (UCDs). The UCDs are unresolved in ground-based imaging and have spectra typical of old stellar systems. Although the UCDs resemble overgrown globular clusters, based on VLT UVES echelle spectroscopy, they appear to be dynamically distinct systems with higher internal velocity dispersions and M/L ratios for a g...
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We present a photometric search for UCD candidates in the nearby galaxy group NGC 1023 (d=11 Mpc) – the poorest environment searched for UCDs yet –, based on wide field imaging with CFHT. After photometric and morphological selection, we obtain a sample of 21 UCD candidates with −12 < MV < −11 mag, if located at NGC 1023’s distance. From spectroscopy taken at Calar Alto observatory, we identify...
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We present the discovery of several Ultra Compact Dwarfs (UCDs) located in field/group environments. Examination of these objects, plus literature UCDs, confirms the existence of two distinct formation channels for these compact stellar systems. We find that the UCDs we have discovered around the group elliptical NGC3923 (and most UCDs in general) have properties consistent with their being the...
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In recent years there has been much interest in the nature of two stars, V407 Vul and RX J0806+1527, which are widely thought to be binary white dwarfs of very short orbital period, 570 and 321 seconds respectively. As such they should be strong sources of gravitational waves and possible ancestors of the accreting AM CVn stars. Monitoring at X-ray and optical wavelengths has established that t...
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It has been suggested that fossil groups could be the canibalized remains of compact groups, that lost energy through tidal friction. However, in the nearby universe, compact groups which are close to the merging phase and display a wealth of interacting features (such as HCG 31 and HCG 79) have very low velocity dispersions and poor neighborhoods, unlike the massive, cluster-like fossil groups...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2011
ISSN: 2041-8205,2041-8213
DOI: 10.1088/2041-8205/737/1/l13