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An Ultra diffuse Galaxy in the NGC 5846 group from the VEGAS survey

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 نشر من قبل Duncan Forbes
 تاريخ النشر 2019
  مجال البحث فيزياء
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Many ultra diffuse galaxies (UDGs) have now been identified in clusters of galaxies. However, the number of nearby UDGs suitable for detailed follow-up remain rare. Our aim is to begin to identify UDGs in the environments of nearby bright early-type galaxies from the VEGAS survey. Here we use a deep g band image of the NGC 5846 group, taken as part of the VEGAS survey, to search for UDGs. We found one object with properties of a UDG if it associated with the NGC 5846 group, which seems likely. The galaxy, we name NGC 5846$_$UDG1, has an absolute magnitude of M$_g$ = -14.2, corresponding to a stellar mass of $sim$10$^8$ M$_{odot}$. It also reveals a system of compact sources which are likely globular clusters. Based on the number of globular clusters detected we estimate a halo mass that is greater than 8$times$10$^{10}$ M$_{odot}$ for UDG1.



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