论文标题
射电天文学可见性数据发现和使用IVOA标准访问
Radio Astronomy visibility data discovery and access using IVOA standards
论文作者
论文摘要
增强对无线电数据的可互操作数据访问已成为国际虚拟天文台联盟(IVOA)中的科学优先事项。这导致了IVOA射电天文学兴趣小组的基础。几位射电天文学家和项目科学家参加了各种项目(NRAO,ASKAP,LOFAR,JIVE,ALMA,SKA,INAF,NENUFAR等)。他们一起为在虚拟观测站(VO)基础架构中更好地整合其服务的道路,并提出扩展IVOA标准以帮助实现这一目标。可以使用IVOA中定义的默许/障碍物规范或通过SIAV2,SODA,SSA,SSA和CONESEARZ在数据产品特定的服务中搜索和检索校准的无线电数据集,例如立方体,图像,光谱和时间序列。但是,无线电可见性数据的属性尚未在VO景观中完全实现。我们需要特定的功能来完善适合射电天文学家需求的数据发现和选择。在这种情况下,DoDonnées天文学中心的VO团队De Strasbourg(CDS)提议考虑淫秽/障碍物规格,并在默默无闻的测量集(MS)元数据(MS)元数据之间建立交叉步行,以获取无线电可视性数据(VD)的数据发现。为了说明无线电VD数据集和VO的科学准备数据之间的粒度差异,该方法将MS数据文件分配到障碍服务服务的数据集列表中,从而在多波长上下文中启用粗晶粒。也通过添加柱元数据或使用DataLink Technique,提供了无线电特定的元数据,例如天线数,频率范围,$ UV $平面覆盖图,频相和频率振幅图,主要和合成的光束。
Enhancing interoperable data access to radio data has become a science priority within the International Virtual Observatory Alliance (IVOA). This lead to the foundation of the IVOA Radio astronomy Interest Group. Several radio astronomers and project scientists enrolled in various projects (NRAO, ASKAP, LOFAR, JIVE, ALMA, SKA, INAF, NenuFAR, etc.) have joined. Together they are paving the way to a better integration of their services in the virtual observatory (VO) infrastructure and propose extension of IVOA standards to help achieving this goal. Calibrated radio datasets such as cubes, images, spectra and time series can already be searched and retrieved using the ObsCore/ObsTAP specification defined in the IVOA, or by data product-specific services like SIAv2, SODA, SSA and ConeSearch. However, properties of radio visibility data are not fully implemented in the VO landscape yet. We need specific features to refine data discovery and selection that are adapted to radio astronomers' need. In this context the VO team at the Centre de Données astronomiques de Strasbourg (CDS) proposes to consider the ObsCore/ObsTAP specification and to establish cross-walks between the ObsCore and the existing Measurement Set (MS) metadata profile for data discovery of radio visibility data (VD). In order to account for the difference in granularity between radio VD datasets and science-ready datasets of the VO, the approach splits a MS data file into a list of datasets served by an ObsTAP service, thus enabling coarse grain discovery in the multi-wavelength context. Radio specific metadata such as number of antennae, frequency ranges, $uv$ plane coverage plots, frequency-phase and frequency-amplitude plots, primary and synthesized beams are also provided either by adding column metadata or by using the DataLink technique.