Enlightening the Universe behind the Milky Way bulge I. Target selection of VVV bulge galaxies
Enlightening the Universe behind the Milky Way bulge I. Target selection of VVV bulge galaxies
复制标题
启示银河系核球背后的宇宙 一、VVV核球星系的目标选择
DOI：
10.1051/0004-6361/202347921
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发表时间：
2024
影响因子：
6.5
通讯作者：
Duplancic F
中科院分区：
文献类型：
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作者：
Duplancic F
上下文太阳系的位置使银河系平面以外的河外源的探测变得复杂。在所谓的回避区（ZOA），恒星拥挤和银河系吸收严重，光学观测受到阻碍。为了发现新的背景星系并完成对ZOA. AIMS的普查，需要进行更长波长的观测。这项工作的目标是识别银河系隆起背后的星系使用近红外（NIR）数据的VISTA变量在Vía Láctea（VVV）survey。为此，我们使用了不同的VISTA科学档案（VSA）工具，以便从VVV凸起区域的320多亿个编目源中提取相关信息。我们发现，最初的光度限制从VSA vvvSource表中的源结合从源提取器获得的恒星星系分离参数的限制是一个成功的策略，实现可接受的污染水平（60%）和高完整性（75%）在建设一个星系目标样本。为了从最初的目标样品中去除污染的银河系源，我们的方法还结合了对假色RGB图像的目视检查，这是一项根据特定程序进行的关键质量控制。根据这种方法，我们发现14 480星系候选人在VVV隆起区域，使这个样本最大的目录中的ZOA日期。此外，这些新的来源提供了一个新的图片宇宙隐藏在幕后的恒星，尘埃，和气体在未经探索的银河系隆起区域。这项工作的结果进一步证明了VVV/VVVX调查的潜力，可以发现和研究大量被银河系遮蔽的星系和河外结构，扩大我们对这个具有挑战性和令人印象深刻的天空区域的宇宙的了解。
Context. The location of the Solar System complicates the detection extragalactic sources beyond the Milky Way plane. The optical observations are hampered in the so-called zone of avoidance (ZOA), where stellar crowding and Galactic absorption are severe. Observations at longer wavelengths are needed in order to discover new background galaxies and complete the census in the ZOA.Aims. The goal of this work is to identify galaxies behind the Milky Way bulge using near-infrared (NIR) data from the VISTA Variables in Vía Láctea (VVV) survey.Methods. To this end, we made use of different VISTA Science Archive (VSA) tools in order to extract relevant information from more than 32 billion catalogued sources in the VVV bulge region. We find that initial photometric restriction on sources from the VSA vvvSource table combined with restrictions on star–galaxy separation parameters obtained from Source Extractor is a successful strategy for achieving acceptable levels of contamination (60%) and high completeness (75%) in the construction of a galaxy target sample. To remove contaminating Galactic sources from the initial target sample, our methodology also incorporates a visual inspection of false-colour RGB images, a crucial quality control carried out following a specifically defined procedure.Results. Under this methodology, we find 14 480 galaxy candidates in the VVV bulge region, making this sample the largest catalogue to date in the ZOA. Moreover, these new sources provide a fresh picture of the Universe hidden behind the curtain of stars, dust, and gas in the unexplored Milky Way bulge region.Conclusions. The results from this work further demonstrate the potential of the VVV/VVVX survey to find and study a large number of galaxies and extragalactic structures obscured by the Milky Way, expanding our knowledge of the Universe in this challenging and impressive region of the sky.