IVOA Simple Image Access

TL;DR

The paper describes the IVOA Simple Image Access protocol (SIA), enabling discovery and retrieval of multi-dimensional astronomical image datasets, including 2-D images and datacubes, based on a standardized data model.

Contribution

It introduces a standardized protocol (SIA) for discovering and accessing multi-dimensional astronomical image data using the ObsCore Data Model.

Findings

Supports discovery of multi-dimensional datasets including datacubes

Enables direct access and retrieval of image data

Defines metadata access and data discovery capabilities

Abstract

The Simple Image Access protocol (SIA) provides capabilities for the discovery, description, access, and retrieval of multi-dimensional image datasets, including 2-D images as well as datacubes of three or more dimensions. SIA data discovery is based on the ObsCore Data Model (ObsCoreDM), which primarily describes data products by the physical axes (spatial, spectral, time, and polarization). Image datasets with dimension greater than 2 are often referred to as datacubes, cube or image cube datasets and may be considered examples of hypercube or n-cube data. In this document the term "image" refers to general multi-dimensional datasets and is synonymous with these other terms unless the image dimensionality is otherwise specified. SIA provides capabilities for image discovery and access. Data discovery and metadata access (using ObsCoreDM) are defined here. The capabilities for drilling down to data files (and related resources) and services for remote access are defined elsewhere, but SIA also allows for direct access to retrieval.