标题： 4FGL-DR2 未关联源的射电对应候选体 显示英文标题

标题： Radio Counterpart Candidates to 4FGL-DR2 Unassociated Sources

摘要： 在费米伽马射线太空望远镜任务期间，大约三分之一的点源被标记为“未关联”，这意味着它们似乎在任何其他波长/频率下都没有已知的对应源。 这个神秘的伽马射线天空部分可能是当前天文学研究中最大的未知领域之一，因此已经被各种技术在不同频率下进行了广泛探测。 射电频率可能是最有成效的，产生了在点源目录每次更新中所记录的大量已识别和关联的活动星系核（AGN）和脉冲星。 在此，我们提供了一个7432个未关联伽马射线区域的射电对应源候选目录，该目录属于第四费米点源目录（4FGL-DR2）的第二数据发布版本。 随后提供了目录和源类型的描述，并讨论了本工作结果如何有助于新的关联和识别。 作为本工作的一部分，我们还提供了一个基于甚大阵列天空调查（VLASS）“快速查看”图像的第一个目录。 显示英文摘要

摘要： For the duration of the Fermi Gamma-Ray Space Telescope's mission, approximately one-third of the point sources detected have been noted as "unassociated," meaning that they seem to have no known counterpart at any other wavelength/frequency. This mysterious part of the gamma-ray sky is perhaps one of the largest unknowns in current astronomical pursuits, and as such has been probed extensively by various techniques at various frequencies. Radio frequencies have been perhaps one of the most fruitful, producing a large fraction of the identified and associated Active Galactic Nuclei (AGN) and pulsars noted in each update of the point source catalogs. Here we present a catalog of 7432 radio counterpart candidates for unassociated gamma-ray fields in the 2nd Data Release of the 4th Fermi Point Source Catalog (4FGL-DR2). A description of the catalog and source types is provided followed by a discussion that demonstrates how the results of this work will aid new associations and identifications. As part of this work, we also present a first catalog derived from "quicklook" images of the Very Large Array Sky Survey (VLASS).