Selecting a data collection allows the user to perform a cone search through a webform (Figure 2) for all data products of that given class overlapping a given pointing. This web interface provides a page on which all the collections present in the registry are listed, including the published Apertif DR1 data sets (Figure 1). The data published in the VO can also be accessed using a web browser at. ALADIN is an interactive sky atlas allowing the user to visualize digitized astronomical images/cubes and superimpose entries from astronomical catalogues or databases. SIA enables the rapid display of images and cubes through all sky atlas tools such as ALADIN. TOPCAT is an interactive graphical viewer and editor for tabular data, it enables the interactive exploration of large tables performing several types of plotting, statistics, editing and visualization of tables. TAP and SAMP enables queries to explore the data in a tabular form using tools such as TOPCAT. In particular, the protocols offered are the Tabular Access Protocol ( TAP ), Simple Application Messaging Protocol ( SAMP) and the Simple Image Access protocol ( SIA ). These interfaces will redirect to ALTA file servers for data access where appropriate. We recommend astronomers to use the VO interfaces described below for data discovery.
The Apertif DR1 data is hosted on the Apertif Long Term Archive ( ALTA ) system.
The science-ready data products as described in Overview (see Available Data Products and Released processed data products), are exposed through standard Virtual Observatory protocols to facilitate their access and exploration.