We present a study of ultracompact dwarf (UCD) galaxies in the Virgo cluster based mainly on imaging from the Next Generation Virgo Cluster Survey (NGVS). Using ∼100 deg 2 of u * giz imaging, we have identified more than 600 candidate UCDs, from the core of Virgo out to its virial radius. Candidates have been selected through a combination of magnitudes, ellipticities, colors, surface brightnesses, half-light radii, and, when available, radial velocities. Candidates were also visually validated from deep NGVS images. Subsamples of varying completeness and purity have been defined to explore the properties of UCDs and compare to those of globular clusters and the nuclei of dwarf galaxies with the aim of delineating the nature and origins of UCDs. From a surface density map, we find the UCDs to be mostly concentrated within Virgo’s main subclusters, around its brightest galaxies. We identify several subsamples of UCDs—i.e., the brightest, largest, and those w...

中文翻译：

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下一代处女座星团调查。XXXIV。处女座星系中的超紧凑矮星系

我们主要基于下一代处女座星团调查（NGVS）的成像技术，对处女座星团中的超小型矮星（UCD）星系进行研究。使用u * giz成像的约100 deg 2，我们已经确定了600多个候选UCD，从处女座的核心一直到其病毒半径。已通过幅度，椭圆率，颜色，表面亮度，半光半径以及径向速度（如果可用）的组合来选择候选人。候选者还通过深NGVS图像进行了视觉验证。定义了不同完整性和纯度的子样本，以探索UCD的性质，并将其与球状星团和矮星系的核进行比较，以描绘UCD的性质和起源。根据表面密度图，我们发现UCD主要集中在处女座的主要子类中，最亮的星系周围。我们确定了UCD的几个子样本，即最亮，最大和最弱的子样本。