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Observation Data Model Core Components and its Implementation in the Table Access Protocol
Version 1.0

IVOA Working Draft 05 March 2011

Interest/Working Group:
Mireille Louys, Francois Bonnarel, David Schade, Patrick Dowler, Alberto Micol, Daniel Durand, Doug Tody, Laurent Michel, Jesus Salgado, Igor Chilingarian, Bruno Rino
Mireille Louys, Daniel Durand, Doug Tody, Alberto Micol


This document discusses the definition of the core components of the Observation data model that are necessary to perform data discovery when querying data centers for observations of interest. It exposes use-cases to be carried out, explains the model and provides guidelines for its implementation as a data access service based on the Table Access Protocol (TAP). It aims at providing a simple model easy to understand and to implement by data providers that wish to publish their data into the Virtual Observatory. This interface integrates data modeling and data access aspects in a single service and is named ObsTAP. It will be referenced as such in the IVOA registries. There will be a separate document to cover the the full Observation data model. In this document, the Observation Data Model Core Components (ObsCoreDM) defines the core components of queryable metadata required for global discovery of observational data. It is meant to allow a single query to be posed to TAP services at multiple sites to perform global data discovery without having to understand the details of the services present at each site. It defines a minimal set of basic metadata and thus allows for a reasonable cost of implementation by data providers. The combination of the ObsCoreDM with TAP is referred to as an ObsTAP service. As with most of the VO Data Models, ObsCoreDM makes use of STC, Utypes, Units and UCDs. The ObsCoreDM can be serialized as a VOTable. ObsCoreDM can make reference to more complete data models such as ObsProvDM, CharDM, Spectrum DM or Simple Spectral Line Data Model (SSLDM).

Status of this document

This is an IVOA Working Draft for review by IVOA members and other interested parties.
It is a draft document and may be updated, replaced, or obsoleted by other documents at any time.It is inappropriate to use IVOA Working Drafts as reference materials or to cite them as other than "work in progress".

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