François Bonnarel

• University of Strasbourg

With the success and widespread of the IVOA Table Access Protocol (1) for discovering and querying tabular data in astronomy, more than one hundred of TAP services exposing altogether 22 thousands of tables are accessible from the IVOA Registries at the time of writing. Currently the TAP protocol presents table data and metadata via a {TAP\_SCHEMA}...

The purpose of the "TAP and the Data Models" Bird of Feathers session was to discuss the relevance of enabling TAP services to deal with IVOA standardized data models and to refine the functionalities required to implement such a capability.

FAIR principles have the intent to act as a guideline for those wishing to enhance the reusability of their data holdings and put specific emphasis on enhancing the ability of machines to automatically find and use the data, in addition to supporting its reuse by individuals. Interoperability, one core of these principles, especially when dealing w...

We present here a provenance management system adapted to astronomical projects needs. We collected use cases from various astronomy projects and defined a data model in the ecosystem developed by the IVOA (International Virtual Observatory Alliance). From those use cases, we observed that some projects already have data collections generated and a...

We present here a provenance management system adapted to astronomical projects needs. We collected use cases from various astronomy projects and defined a data model in the ecosystem developed by the IVOA (International Virtual Observatory Alliance). From those use cases, we observed that some projects already have data collections generated and a...

The International Virtual Observatory Alliance (IVOA) has developed and built, in the last two decades, an ecosystem of distributed resources, interoperable and based upon open shared technological standards. In doing so the IVOA has anticipated, putting into practice for the astrophysical domain, the ideas of FAIR-ness of data and service resource...

Recently the International Virtual Observatory Alliance (IVOA) released a standard to structure provenance metadata, and several implementations are in development in order to capture, store, access and visualize the provenance of astronomy data products. This BoF will be focused on practical needs for provenance in astronomy. A growing number of p...

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.)...

The IVOA Provenance Data model defines entities, agents and activities as container classes to describe the provenance of datasets, with the executed tasks and responsibilities attached to agents. It also provides a set of classes to describe the activities type and their configuration template, as well as the configuration applied effectively duri...

www.ivoa.net/twiki/bin/view/IVOA/IvoaDataModel

The European Open Science Cloud (EOSC) is in its early stages, but already some aspects of the EOSC vision are starting to become reality, for example the EOSC portal and the development of metadata catalogues. In the astrophysical domain already exists an open approach to science data: the Virtual Observatory view put in place by the International...

In the context of astronomy projects, scientists have been confronted with the problem of describing in a standardized way how their data have been produced. As presented in a talk at last year's ADASS, the International Virtual Observatory Alliance (IVOA) is working on the definition of a Provenance Data Model, compatible with the W3C PROV model,...

The IVOA (International Virtual Observatory Alliance) has proposed a standard for capturing the provenance metadata in the production and distribution of astronomical data. We present an implementation in a triplestore for the provenance information recorded for a collection of astronomical images. The ontology applied is derived from PROV-O from t...

In the context of astronomy projects, provenance information is important to enable scientists to trace back the origin of a dataset. It is used to learn about the people and organizations involved in a project and assess the quality of the dataset as well as the usefulness of the dataset their scientific work. As part of the data model group in th...

We developed several pieces of software to enable the tracking of provenance information for the large-scale complex astronomical observatory CTA, the Cherenkov Telescope Array. Such major facilities produce data that will be publicly released to a large community of scientists. There are thus strong requirements to ensure data quality, reliability...

High speed Internet and the evolution of data storage space in terms of cost-effectiveness has changed the way data are managed today. Large amounts of heterogeneous data can now be visualized easily and rapidly using interactive applications such as “Google Maps”. In this respect, the Hierarchical Progressive Survey (HiPS) method has been develope...

This document describes the Server-side Operations for Data Access (SODA) web service capability. SODA is a low-level data access capability or server side data processing that can act upon the data files, performing various kinds of operations: filtering/subsection, transformations, pixel operations, and applying functions to the data.

The activities of the Centre de Donnees astronomiques de Strasbourg (CDS) are reviewed. They include: SIMBAD, the reference database for the identification and bibliography of astronomical objects, the catalog service with the new VizieR Catalogue Browser developed as a joint effort by CDS and ESA/ESRIN and the WWW server. The future evolution of t...

The Centre de Données astronomiques de Strasbourg (CDS) has been collecting and distributing astronomical data for more than 25 years. It develops and maintains several reference databases, mainly an object database (SIMBAD), a catalogue database (VizieR) and an image database (Aladin). An important aspect consists also in developing links between...

The IVOA Data Access Layer (DAL) working group was created in 2002 to define protocols to homogenize data discovery, data description, data retrieval, and data access processes. We describe its history and status today, and look at current trends for future development of the DAL protocols.

We present the last developments on the IVOA Provenance data model, mainly based on the W3C PROV concept. In the context of the Cherenkov astronomy, the data processing stages imply both assumptions and comparison to dedicated simulations. As a consequence, Provenance information is crucial to the end user in order to interpret the high level data...

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...

This document describes the linking of data discovery metadata to access to the data itself, further detailed metadata, related resources, and to services that perform operations on the data. The web service capability supports a drill-down into the details of a specific dataset and provides a set of links to the dataset file(s) and related resourc...

Scientific exploitation of the ever increasing volumes of astronomical data requires efficient and practical methods for data access, visualisation, and analysis. Hierarchical sky tessellation techniques enable a multi-resolution approach to organising data on angular scales from the full sky down to the individual image pixels. Aims. We aim to sho...

This paper presents a tutorial explaining the use of Virtual Observatory tools in high energy astrophysics. Most of the tools used in this paper were developed at the Strasbourg astronomical Data Center and we show how they can be applied to conduct a multi-instrument, multi-wavelength analysis of sources detected by the High Energy Stereoscopic Sy...

In the upcoming era of large scale, geographically distributed, varied sources of astronomical data, a standard, simple and flexible way to access this data is necessary and useful for astronomers across the globe. Most of the modern surveys such as the Sloan Digital Sky Survey (SDSS) are available in well organized tabular formats. The Table Acces...

We present to the astronomical community an algorithm for the detection of low surface brightness (LSB) galaxies in images, called MARSIAA (MARkovian Software for Image Analysis in Astronomy), which is based on multi-scale Markovian modeling. MARSIAA can be applied simultaneously to different bands. It segments an image into a user-defined number o...

TapHandle is a Web application merging multiple services based on the IVOA Table Access Protocol (TAP) in one page. TAP resources are presented in an expandable tree whose leaves represent SQL tables. Both table description and content can be immediately displayed. A smart ADQL editor helps to setup queries on one table. A shopping cart facility al...

The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) is a high impact scientific program which will see its final official release open to the world in 2012. That release will seal the legacy aspect of the survey which has already produced a large collection of scientific articles with topics ranging from cosmology to the Solar system. The sur...

Canada and France joined a large fraction (~50%) of their dark and grey telescope time from mid-2003 to early 2009 for a large project, the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). The data acquisition and calibration has been a major undertaking for the Canadian and French communities: more than 2300 hours over 5 years (an equivalent...

The Simple Spectral Access (SSA) Protocol (SSAP) defines a uniform interface to remotely discover and access one dimensional spectra. SSA is a member of an integrated family of data access interfaces altogether comprising the Data Access Layer (DAL) of the IVOA. SSA is based on a more general data model capable of describing most tabular spectropho...

The International Virtual Observatory Alliance (IVOA) developed numerous interoperability standards during the last several years. Most of them are quite simple to implement from the technical point of view and even contain "SIMPLE" in the title. Does it mean that it is also simple to build a working VO resource using those standards? Yes and no. "...

The Characterisation data model is a standard of the International Virtual Observatory Alliance (IVOA) that describes observational datasets in the multi-dimensional parameter space. Defining three properties: coverage, resolution, and sampling along different physical axes (e.g. spatial, spectral, flux) with variable level of details for the descr...

This document defines the high level metadata necessary to describe the physical parameter space of observed or simulated astronomical data sets, such as 2D-images, data cubes, X-ray event lists, IFU data, etc.. The Characterisation data model is an abstraction which can be used to derive a structured description of any relevant data and thus to fa...

This document defines 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...

From the need to extend the display outside the boundaries of a single image, the Aladin team recently developed a new feature to visualize wide areas or even all of the sky. This all-sky view is particularly useful for visualization of very large objects and, with coverage of the whole sky, maps from the Planck satellite. To improve on this capabi...

Aladin, developed over 10 years at CDS, has evolved from a simple sky atlas to become a rich and powerful portal able to access, visualize and manipulate images and catalog data. Aladin is widely used in the Virtual Observatory community and beyond. Version 7 of Aladin is open source, and recent developments have been focused on enabling all-sky br...

The NGVS is mapping the Virgo Cluster with a depth making possible to detect very low surface brightness (LSB) structures, such as faint dwarf galaxies. To extract these from just above the sky noise and make statistical studies of their properties, we use the software MARSIAA (MARkovian Software for Image Analysis in Astronomy). This segmentation...

The last few years have seen the emergence of new visualization tools such as Google Sky and Microsoft World Wide Telescope supporting immediate full sky panning and zooming. All these tools have in common a view of the sky based on a hierarchical multi-resolution sky tessellation. The aim is to load and draw the good pieces of the sky at the good...

The new release of the SPECFIND radio cross-identification catalogue, SPECFIND V2.0, is presented. It contains 107488 cross-identified objects with at least three radio sources observed at three independent frequencies. Compared to the previous release the number of entry radio catalogues is increased from 20 to 97 containing 115 tables. This large...

Aladin is an interactive sky atlas for visualization and manipulation of digitized astronomical images and catalogues. It is widely used for browsing and viewing multiwavelength image data, for overlay and cross-matching of catalogues, and for preparing observations. This Aladin demo has demonstrated new features available in the last public releas...

In an inter-disciplinary collaborative project, we have designed a framework to execute statistical image analysis techniques for multiwavelength astronomical images. This paper describes an interactive tool, AIDA_WF , which helps the astronomer to design and describe image processing workflows. This tool allows designing and executing processing s...

Dealing with multi-wavelength data and associated metadata has become a must-have in modern astronomy. The Aladin VO (Virtual Observatory) portal can help in this task at various levels: It provides access through VO standards to numerous data services delivering tables, images and spectra. It offers visualization, exploration and combination of mu...

We present preliminary simple interfaces developed to enable students, teachers, amateur astronomers and general public to access and use the wealth of astronomical data available in ground-based and space archives through the European Virtual Observatory (EuroVO). The development of these outreach interfaces are the aim of a workpackage of EuroVO-...

After a short introduction to workflow systems, we focus on the use of "Characterization", an IVOA standard, in a workflow test bed architecture. The execution of a workflow may require substantial computing resources and this can take a significant amount of time. Our goal is to go as far as possible in the validation of the workflow process befor...

We present a new feature in progress in ALADIN software : an interactive sky browser. The aim is to give a way to browse the sky as easily as outreach softwares can do, but geared for astronomers. The user can visualize a wide field and move seamlessly on the whole sky. This navigation mode will be available for some ALADIN archive surveys, the nee...

Aladin can be used as a VO portal for 3D spectroscopy DAL services. The new release is able to ingest data cubes and display them in movie mode. Lambda maps and spectra at one position can be excerpted. SIA services retrieving data cubes allow to describe in the metadata tree several access modes to the same dataset via DAL query response extension...

We have designed a new technique for the detection of Low Surface Brightness galaxies based on local background/source separation using Markovian analysis. This method helps to estimate smooth local variations of the background and therefore allows for determining source candidates as faint as LSB galaxies. For each source an average density profil...

The Aladin interactive sky atlas has been first released in 1999, aiming at providing an easy way to visualize digitized astronomical images and superimpose catalogue entries from databases such as Simbad or VizieR. While keeping its fundamental strengths (user friendliness, size suitable for applet usage), Aladin has grown since into a Virtual Ob...

We propose a formalised description of IFU datasets sufficient for providing data discovery, access and processing in the Virtual Observatory framework.

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 Characteris...

We use PostgreSQL DBMS for storing XML metadata, described by the IVOA Characterisation Data Model. Initial XML type support in the PostgreSQL has recently been implemented. We make heavy use of this feature in order to provide comprehensive search over Characterisation metadata tree. We built a prototype of the Characterisation metadata query serv...

Three cornerstones for the 3D data support in the Virtual Observatory are: (1) data model to describe them, (2) data access services providing access to fully-reduced datasets, and (3) client applications which can deal with 3D data. Presently all these components became available in the VO. We demonstrate an application of the IVOA Characterisatio...

The CDS value-added bibliographic services, SIMBAD and VizieR, are updated daily. Most of the information comes from the astronomical literature and the update mechanism is different for different types of information. The semi-automated SIMBAD data flow is described and the synergy between astronomers, specialized librarians and computer engineers...

A new version of SIMBAD, SIMBAD4, has been developed at the CDS. Basically, everything that SIMBAD does today will be possible with the new version but not necessarily in the same way. The new features will concern the queries, flux, object types and hierarchical links.

We consider here image analysis pipelines and examine how data and processes could be described in the context of the VO. The tasks chain is considered as a workflow, not only in terms of computing and resource allocation as in the Grid community, but in terms of data analysis know-how. Such pipelines may be published as coarse grain tool boxes and...

The reduction and segmentation of multiwavelength images become problematic when the number of bands increases. Integral field spectroscopy and other instrument designs allowing for enhanced spectral and spatial resolution lead to extremely large hyperspectral data cubes (typically 370 million pixels per exposure for the MUSE instrument). New analy...

Major evolutions have been implemented in the three main CDS databases in 2006. SIMBAD 4, a new version of SIMBAD developed with Java and PostgreSQL, has been released. Il is much more flexible than the previous version and offers in particular full search capabilities on all parameters. Wild card can also be used in object names, which should eas...

Many people develop tools for image processing in various languages (C, C++, FORTRAN, MATLAB, etc) but do not diffuse them. One of the reasons is the portability and also the difficulty to make them collaborate with other tools. We have developed an architecture in which such tools can be wrapped and accessed through a standardized way (CGI and Web...

The VOTech design study on future tools started in spring 2005. This project, co-funded by the EC, produces design documents and software prototypes for new VO-compliant end-user tools. It is based on the experience and feedback of precursor projects and on input from the scientific user community. This status report details a number of early deliv...

The CDS was established in 1972 with the aim of collecting, selecting, evaluating and distributing information to the world wide astronomical community. The Catalogue of Stellar Identification (CSI) database was created from the early years. Later renamed SIMBAD, it quickly reached half a million objects. This represented a technical challenge on m...

3D spectroscopy is a modern and promising observational technique, that allows spectra to be obtained for a contiguous area of the sky, resulting in a 3-dimensional data structure or 'data cube' containing spectral and spatial information. During the last 15 years a considerable amount of 3D data was obtained on large optical, sub-mm and radio tele...

Created nine years ago, the Aladin sky atlas tool has become a widely-used VO (Virtual Observatory) portal capable of locating data of interest, accessing and exploring distributing datasets, and visualizing multi-wavelength data. Its compliance with existing or emerging VO standards, interconnection with other visualization or analysis tools, and...

The Centre de Données astronomiques de Strasbourg (CDS) develops a set of interlinked services, SIMBAD, VizieR, ALADIN, the Dictionary of Nomenclature, which can be used to find information about particular objects or regions of the sky, or can be sampled by criteria. An example of more advanced usage is also given. New functionalities will be deve...

The Image archive model described here has been developed within the scope of the IDHA (Images Distribuées Hétérogènes pour l’Astronomie) project. The IDHA project led by CDS, associates image processing scientists of LSIIT (Strasbourg), and astronomers of several French Institutes including TERAPIX from IAP, and Queen’s University (Belfast). IDHA...

Aladin, the CDS interactive sky atlas is one of the important interoperability tools of the astronomy Web. Several recent improvements prepare it for use as a portal to the Phase A of the Astrophysical Virtual Observatory (AVO), as shown by its use as a testbed for the AVO-January 2003 demonstration (Quinn, P., 2002).

We present the new functionalities implemented in the last major release of ALADIN (v3): multi-panel view, creation of subimages for specific regions of interest, and image reprojection. Current developments for the display of solar system objects and of instrument field of views are also described.

Since its first version created 8 years ago, Aladin has been continuously developed, and has been recently used as the main component of the Astrophysical Virtual Observatory prototype, demonstrating the power of VO interoperability standards for enabling real science. But interoperability is not just a set of standards used to describe accurately...

The Centre de Donnees astronomiques de Strasbourg (CDS) maintains several widely used databases and services. Among significant recent evolutions: - a new version of SIMBAD (SIMBAD 4), based on the PostgreSQL database system, has been developed, to replace the current version which has been operational since 1990. It allows new query and sampling...

A new method for the multiband segmentation of a spectroscopic line data cube is presented. This method is intended to help astronomers to handle complex spectroscopic line data cubes where the inspection of the channel and moment maps is difficult. Due to the Hughes phenomenon, the number of input images for the segmentation process is limited. Th...

This paper proposes a reduction-segmentation scheme for radio- astronomical cubes. In order to avoid the curse of dimen- sionality phenomenon, a reduction technique is proposed as preprocessing step before classification. On each site of the image a spectrum is observed, exhibiting few spectral rays, modeled as a weighted mixture of selected Gaussi...

The CDS services, SIMBAD, VizieR, and Aladin, are important building blocks of the Virtual Observatory. Collaboration with VO projects, in the European Astrophysical Virtual Observatory consortium, and with the US National Virtual Observatory framework project, VO-India initiative, and other efforts, has been very fruitful in the last years. New fu...

Interoperability in Virtual Observatories is based on standards for interchange formats, and protocols. Using real science cases, we present example VO tools based on the AVO prototypes and the CDS services, which implement the new and emerging VO standards. We discuss how these standards, such as VOTable, UCDs and data models enable interoperabili...

We present the main new features of the Aladin interactive sky atlas (version 2.0, November 2003). The Aladin tool is able to query a remote server providing new VO DAL (Data Access Layer) outputs and to interpret the result. Aladin is able to build a metadata tree from the description of a dataset, in order to easily browse through all data availa...

The Astrophysical Virtual Observatory (AVO) prototype is a suite of tools that serves as a testbed for scientific and technical use cases. For instance, it supports the Simple Image Access (SIA) protocol, hierarchical browsing based on the IDHA data model and fully exploits the potential of Unified Content Descriptors (UCD). Each of the software c...

The status of the CDS services is described. In particular, new features developed in the context of the Virtual Observatory and using IVOA-discussed standards have been included in the public version of the services, e.g., filter capabilities using Unified Content Descriptors (UCDs) in VizieR and Aladin, customized hierarchical data tree using the...

Browsing and providing access to large local and distributed datasets is an important aspect of enabling Virtual Observatories. We present an example implementation of a meta-data tree in the Astrophysical Virtual Observatory prototype tool. This is a dynamically built

In this article we describe how the GLU system (Uniform Link Generator) allows the Aladin browsing tool to integrate several image and data servers through a single interface. We describe how it works, how it is updated and how it is implemented in a Java context. We also present the future evolution we foresee for the GLU system in order to allow...

Europe's Astrophysical Virtual Observatory (AVO) developed a prototype system and continues to improve it. A board of 50 scientists - the AVO science working group - is advising the project team with the goal of maximizing the scientific return. In order to implement their recommendations a number of VO key technologies come into play. Each of the...

Une technique de réduction de données astronomiques comme étape préliminaire à une classification d'images de galaxies lointaines est présentée. Le classifieur retenu est basé sur une modélisation markovienne causale en échelle sur le quadarbre. Ce papier présente les résultats encourageants obtenus par cette approche.

The Astrophysical Virtual Observatory Project (PI: P. Quinn, ESO) has three Work Areas: Science case (P. Benvenuti, ST-ECF), Interoperability (F. Genova, CDS) and Advanced technologies (A. Lawrence, AstroGrid). The development of an Interoperability prototype, implementing a set of European archives into VizieR and Aladin, in collaboration with all...

The new context of the on-going efforts towards an international Virtual Observatory has a significant impact on current CDS developments. While a strong emphasis remains on data quality, and permanent update of databases, new tools and additional links are being brought forward through collaboration to the AVO consortium, and with NVO and other VO...

A review of issues in image compression is presented, with a strong focus on the wavelet transform and other closely related multiresolution transforms. The roles of information content, resolution scale, and image capture noise, are discussed. Experimental and practical results are reviewed.

Efficient interoperability tools between the astronomical data servers are one of the key elements of the Virtual Observatory. The HTTP protocol combined with the XML syntax is a pragmatic solution to increase this interoperability. The CDS approach is to build progressively a set of operational descriptions for information exchanged between astron...

We present some recent developments in the CDS services. These include new surveys available in VizieR and Aladin, an increased number of archive links in VizieR and Aladin, visualization for spectra and time series in VizieR, new query facilities in SIMBAD, and scripting facilities in Aladin. Overall interoperability features are also emphasized.

Interoperability between heterogeneous, distributed services, is one of the key features of the Virtual Observatory. CDS develops widely used interoperability tools, VizieR and Aladin. Tabular data, catalogues, published tables, surveys, and lists of observations in archives, are federated in VizieR, with active links to data, images, spectra and t...

The Centre de Donnees astronomiques de Strasbourg (CDS) develops a set of value-added services, widely used for information retrieval, observation preparation, data interpretation, etc. SIMBAD, VizieR, Aladin and the 'Dictionary of Nomenclature' integrate heterogeneous selected information from observatory archives, sky surveys and publications. Ea...

Performance results using wavelet and other multiresolution transforms are described. The roles of information content, resolution scale, and image capture noise, are discussed. Delivery systems for a range of large image repositories from areas which include medical, astronomy and graphic arts are described, as standalone systems for use on portab...

The Maximum Entropy Method is well-known and widely used in image analysis in astronomy. In its standard form it presents certain drawbacks, such an underestimation of the photometry. Various refinements of MEM have been proposed over the years. We review in this paper the main entropy functionals which have been proposed and discuss each of them....

ALADIN is a powerful tool for data interpretation, which allows one to integrate survey images and catalogues with reference information from SIMBAD, NED, VizieR, and with images from observatory archives. Recent evolution of the ALADIN software and of the image database are presented. The main facts are the following: - The AladinJava standalone v...