[Paper Review] ASPID-SR: Prototype of a VO-compliant Science-Ready Data Archive

Igor Chilingarian, V. L. Afanasiev+4 more|ArXiv.org|Nov 2, 2007

Scientific Computing and Data Management3 citations

TL;DR

ASPID-SR presents a prototype science-ready data archive compliant with the IVOA Characterisation Data Model, enabling multi-level metadata characterization of heterogeneous 3D spectroscopic, photometric, and interferometric datasets. It implements VO-compliant access via SIAP/SSAP, ADQL/x web services, and HTTP metadata queries, demonstrating the model's applicability to complex astronomical data with full interoperability and efficient discovery capabilities.

ABSTRACT

ASPID stands for the "Archive of Spectral, Photometric, and Interferometric Data". The world largest collection of raw 3D spectroscopic observations of galactic and extragalactic sources is provided. ASPID-SR is a prototype of an archive of heterogeneous science ready data, fed by ASPID, where we try to exploit all the power of the IVOA Characterisation Data Model. Multi-level Characterisation metadata is provided for every dataset. The archive provides powerful metadata query mechanism with access to every data model element, vital for the efficient scientific usage of a complex informational system. We provide a set of access interfaces: SIAP/SSAP, HTTP-based characterisation metadata query, Web-service accepting ADQL/x.

Motivation & Objective

• To develop a science-ready data archive compliant with the IVOA Characterisation Data Model for heterogeneous astronomical datasets.
• To enable efficient data discovery and retrieval through rich, multi-level metadata characterization of spatial, spectral, temporal, and flux axes.
• To support interoperability in the International Virtual Observatory by implementing standardized VO access protocols such as SIAP/SSAP and ADQL/x.
• To preserve source-result linkage between raw data (ASPID) and reduced, science-ready data (ASPID-SR), ensuring data provenance.

Proposed method

• The backend uses PostgreSQL with XMLType support and pgSphere extension for spherical geometry operations to enable spatial queries on celestial coordinates.
• Multi-level characterisation metadata is structured for all axes (spatial, spectral, time, flux) using the IVOA Characterisation Data Model, including reference values, bounds, and precision.
• The archive implements a PHP-based HTTP interface for direct dataset access and exposes metadata through a standardized query mechanism.
• VO-compliant access interfaces are provided: SIAP/SSAP for spatial and spectral access, and a web service accepting ADQL/x for advanced metadata and data queries.
• Data reduction is performed by PI teams or LSPEO members, with only data older than two years or explicitly released by PIs made available in the science-ready archive.
• The system maintains a persistent source-result connection between ASPID (raw data) and ASPID-SR (reduced data), ensuring traceability and reproducibility.

Experimental results

Research questions

• RQ1 How can the IVOA Characterisation Data Model be effectively applied to complex 3D astronomical datasets such as IFU and Fabry-Perot datacubes?
• RQ2 What level of metadata granularity is required to enable efficient scientific discovery and interoperability in a heterogeneous data archive?
• RQ3 To what extent can VO-compliant access protocols (SIAP/SSAP, ADQL/x) be used to query rich, multi-dimensional metadata in a science-ready data archive?
• RQ4 How can data provenance and source-result linkage be preserved in a science-ready archive derived from raw observational data?

Key findings

• ASPID-SR is one of the first implementations of the IVOA Characterisation Data Model for 3D astronomical datasets, demonstrating its feasibility and utility in complex data systems.
• The archive provides multi-level characterisation metadata for all axes (spatial, spectral, time, flux), including reference values, bounds, and precision, enabling fine-grained data discovery.
• The system successfully implements VO-compliant access interfaces, including SIAP/SSAP, HTTP-based metadata queries, and a web service accepting ADQL/x, enabling standardized data retrieval.
• Only data older than two years or explicitly released by PIs is available in ASPID-SR, ensuring compliance with SAO RAS data policy while preserving scientific usability.
• The archive maintains a persistent link between raw data in ASPID and reduced data in ASPID-SR, supporting data provenance and reproducibility.
• The implementation demonstrates that the IVOA Characterisation Data Model can support efficient, self-descriptive, and interoperable access to complex, heterogeneous astronomical datasets.