IVOA Dataset Metadata Model

Table of Contents

1.     model: ds
2.     Packages and Types
2.1     [root package]
2.2     package: dataset
2.2.1     objectType: Collection
2.2.2     objectType: Contact
2.2.3     objectType: Contributor
2.2.4     enumeration: CreationType
2.2.5     objectType: Creator
2.2.6     objectType: Curation
2.2.7     objectType: DataID
2.2.8     objectType: DataModel
2.2.9     enumeration: DataProductType
2.2.10     objectType: Dataset
2.2.11     objectType: Publication
2.2.12     objectType: Publisher
2.2.13     enumeration: RightsType
2.2.14     enumeration: SpectralBandType
2.3     package: experiment
2.3.1     objectType: AstroTarget
2.3.2     objectType: BaseTarget
2.3.3     objectType: Derived
2.3.4     objectType: DerivedElement
2.3.5     objectType: DerivedScalar
2.3.6     objectType: Facility
2.3.7     objectType: Instrument
2.3.8     objectType: ObsConfig
2.3.9     objectType: ObsDataset
2.3.10     objectType: Observation
2.3.11     objectType: Proposal
2.3.12     objectType: Target
2.4     package: party
2.4.1     objectType: Individual
2.4.2     objectType: Organization
2.4.3     objectType: Party
2.4.4     objectType: Role
3.     vodml-id-s
4.     Imported Models
4.1     ivoa
4.2     meas

1. Model: IVOA Dataset Metadata Model (ds)

Authors : Mark Cresitello-Dittmar, Francois Bonnarel, Omar Laurino, Gerard Lemson, Mireille Louys, Arnold Rots, Doug Tody, and the IVOA Data Model Working Group.
Date : 2017-04-28T15:13:01
Version : 1.0
Previous version: : 0.x
Abstract : This document provides a data model describing the structure and content of generic Dataset metadata for the IVOA. This is a high-level model which is to be referenced and extended by other models describing specific types of Datasets and Data products. In this document, we specify the generic Dataset, as well as an ObservationDataset model which covers the class of Datasets which are derived from an Observation. At the time of this writing, there is no formal Observation-Experiment model for the IVOA, so we include a hypothetical Observation-Experiment model to serve as a placeholder.
Diagram : The following diagram has been generated from the model using the GraphViz tool.
The classes and packages in the diagram can be clicked and are mapped to the descriptions of the corresponding element elsewhere in the document.

2.Model contents: Packages and Types

The following sub-sections present all packages in the model with their types. The packages are listed here in alphabetical order. Each sub-section contains a description of the package and a table containing its various features.

2.1 [root package]

Model ds
child package(s) dataset experiment party

2.2 package: dataset

vodml-id dataset
description Dataset Metadata package
parent ds
Object types Collection Contact Contributor Creator Curation DataID DataModel Dataset Publication Publisher
Enumerations CreationType DataProductType RightsType SpectralBandType

2.2.1 objectType: Collection

vodml-id dataset.Collection
description A generic organizational construct which allows Datasets to be associated with each other by a set of Collection properties. Datasets tagged with the same Collection properies can be assumed to have some degree of compatibility.
package dataset
attributes
name feature value
name type ivoa:string
vodml-id dataset.Collection.name
multiplicity 1
description The values are generally defined by the creating entity. Examples: "WFC", "Sloan", "BFS Spectrograph", "MSX Galactic Plane Survey".

2.2.2 objectType: Contact

vodml-id dataset.Contact
description Contact information for a person or entity. Contact is modeled as a Role played by a particular person or entity (Party). We subset the type of Party to include only Individuals. This includes both a physical person, or proxy service such as a helpdesk.
package dataset
extends Role [ds:party.Role]
constraints
party.Role.party:Individual[1]

2.2.3 objectType: Contributor

vodml-id dataset.Contributor
description Contributor is modeled as a Role played by a Party or entity who participated in the generation of the Dataset.
package dataset
extends Role [ds:party.Role]
attributes
name feature value
acknowledgment type ivoa:string
vodml-id dataset.Contributor.acknowledgment
multiplicity 1
description Acknowledgment expression for the contributor. Users of the dataset should include these in subsequent credits and acknowledgements. The expression should be formatted as desired by the contributor.

2.2.4 enumeration: CreationType

vodml-id dataset.CreationType
description Enumeration of dataset creation types.
package dataset
literals
name feature value
ARCHIVAL vodml-id dataset.CreationType.ARCHIVAL
description Indicates that it is one of a collection of datasets generated in a systematic, homogeneous way and is stored statically (or at least versioned). It will be possible to regenerate this dataset at a later date. The remaining types imply on-the-fly manipulation.
CUTOUT vodml-id dataset.CreationType.CUTOUT
description Indicates that the dataset was created "on-the-fly", by subsetting, but not by modifying values.
FILTERED vodml-id dataset.CreationType.FILTERED
description May involve excluding data prior to binning into samples, also "on-the-fly"
MOSAIC vodml-id dataset.CreationType.MOSAIC
description Combines multiple original datasets "on-the-fly"
SPECTRAL_EXTRACTION vodml-id dataset.CreationType.SPECTRAL_EXTRACTION
description Has been extracted, for example, from a spectral data cube.
CATALOG_EXTRACTION vodml-id dataset.CreationType.CATALOG_EXTRACTION
description Has been extracted from a catalog.

2.2.5 objectType: Creator

vodml-id dataset.Creator
description Creator is modeled as a Role played by the organization or entity which created the Dataset.
package dataset
extends Role [ds:party.Role]

2.2.6 objectType: Curation

vodml-id dataset.Curation
description The Curation object provides metadata assigned by the entity responsible for the support of the dataset content as well as identifying metadata about that entity. It is assembled from definitions provided by the IVOA standard document, "Resource Metadata for the Virtual Observatory; Version 1.12" (Resource Metadata). Here, we provide a brief description of each field for easy reference, along with a notation of its mapping to the Resource Metadata document (RM:field), where the reader may find more detailed information.
package dataset
attributes
name feature value
publisherDID type ivoa:anyURI
vodml-id dataset.Curation.publisherDID
multiplicity 0..1
description IVOA dataset identifier assigned by the publisher to uniquely identify the dataset within its holdings. Typically, the basis of this identifier will be the publisher ID. However, if the publisherchooses to use a 'global index service' such as ADS to obtain persistent identifiers for their datasets, rather than generate their own, that identifier should be used both here and for DataID.datasetID. Note: this model also defines a creator dataset ID (DataID.creatorDID), these will differ if the publishing entity is not the creator of the dataset. Values are to be expressed as dataset identifiers using the syntax described in "IVOA Identifiers"
version type ivoa:string
vodml-id dataset.Curation.version
multiplicity 0..1
description Version of the curated dataset, assigned by the publisher. This is an independent versioning from DataID.version that allows the publisher to track changes to the high level dataset metadata (e.g. curation metadata, identifiers, etc.) without effecting the creator defined dataset version. The value may be based on the DataID.version (e.g. by adding a sub-version extension), or an independent versioning. There are no format restrictions on the value. (RM:Curation.Version)
releaseDate type ivoa:datetime
vodml-id dataset.Curation.releaseDate
multiplicity 0..1
description Date the curated dataset was last modified. (RM:Curation.Date)
rights type RightsType [ds:dataset.RightsType]
vodml-id dataset.Curation.rights
multiplicity 0..1
description TODO : Missing description : please, update your UML model asap.
compositions
name feature value
contact type Contact [ds:dataset.Contact]
vodml-id dataset.Curation.contact
multiplicity 0..1
isOrdered false
description Contact information of the person/entity responsible for the content of the dataset. We recommend using a generic 'helpdesk' type contact rather than individuals whose information may more easily become obsolete. (RM:Curation.Contact)
publisher type Publisher [ds:dataset.Publisher]
vodml-id dataset.Curation.publisher
multiplicity 1
isOrdered false
description The entity making the data available. (RM:Curation.Publisher)
reference type Publication [ds:dataset.Publication]
vodml-id dataset.Curation.reference
multiplicity 0..*
isOrdered false
description Zero or more bibliographic or documentation references associated with the dataset. Each instance provides a single forward link to a major publication which references the dataset. (RM:General.Source)

2.2.7 objectType: DataID

vodml-id dataset.DataID
description The Data Identification object (DataID) stores the dataset identifiers and other metadata typically assigned by the dataset creator. The Dataset IDs in this object must comply with the syntax for dataset identifiers defined in the "IVOA Identifiers" document, including the use of 'stop' characters to identify specific datasets that are not individually in the registry. e.g., ivo://example.net/aservice?2013/5/2342. Much of the content of this object is assembled from various definitions in the IVAO Resource Metadata document. Here, we provide a brief description of each field for easy reference, along with a notation of its mapping to the Resource Metadata document (RM:field), where the reader may find more detailed information.
package dataset
attributes
name feature value
title type ivoa:string
vodml-id dataset.DataID.title
multiplicity 1
description A free form string giving a title for the dataset. (RM:Identity.Title)
datasetID type ivoa:anyURI
vodml-id dataset.DataID.datasetID
multiplicity 0..1
description If the dataset is registered with an external 'global index service' such as ADS, the publisher may include that identifier here. This provides a common, persistent identifier for the dataset, and possible access point to follow for information on publications and other related datasets. Note: the same dataset published at more than one location would have different Curation.publisherDID values, but the same DataID.datasetID. eg: "ivo://ADS/Sa.CXO?obsid=1234", "ivo://ADS/sh.hut#ngc4151_141"
creatorDID type ivoa:anyURI
vodml-id dataset.DataID.creatorDID
multiplicity 0..1
description The dataset identifier assigned by the creator. Here, the authority-id of the identifier must be that of the creator. It is used to identify the original exposure of the dataset in an archive, and will remain static regardless of where the dataset is published. The creator ID will not necessarily change even if the VO object in question is a cutout or is otherwise further processed.
version type ivoa:string
vodml-id dataset.DataID.version
multiplicity 0..1
description Version assigned by the creator, reflecting the production version of the dataset. This value should only be changed by the creator, upon the new release of a dataset. There are no format restrictions or specifications on the versioning scheme.
date type ivoa:datetime
vodml-id dataset.DataID.date
multiplicity 0..1
description Data processing or creation date (RM:Curation.Date).
creationType type CreationType [ds:dataset.CreationType]
vodml-id dataset.DataID.creationType
multiplicity 0..1
description The dataset creation type describes the nature or genre of the content. (RM:General.Type). Note: This field provides information about the process by which the dataset was created. As the Observation/Experiment model matures, this may evolve into a provenance element on the Experiment type.
compositions
name feature value
collection type Collection [ds:dataset.Collection]
vodml-id dataset.DataID.collection
multiplicity 0..*
isOrdered false
description The dataset is associated with zero or more Collections (instrument name, survey name, etc.) . Each instance identifies a tag indicating some degree of compatibility with other data sharing the same Collection properties.
contributor type Contributor [ds:dataset.Contributor]
vodml-id dataset.DataID.contributor
multiplicity 0..*
isOrdered false
description Persons or entities who contributed to the generation of the scientific content of the dataset. Users of the dataset should include these in subsequent credits and acknowledgements. (RM:Curation.Contributor)
creator type Creator [ds:dataset.Creator]
vodml-id dataset.DataID.creator
multiplicity 0..1
isOrdered false
description The institution or entity which created the dataset.

2.2.8 objectType: DataModel

vodml-id dataset.DataModel
description This object provides specific information regarding the data model and version thereof that a dataset represents. This information is primarily an aide to (de)serialization of the dataset. As such, it would better be defined by serialization conventions. In lieu of such conventions, we include this object and representative serialization examples for the primary file formats VOTable and FITS.
package dataset
attributes
name feature value
name type ivoa:string
vodml-id dataset.DataModel.name
multiplicity 1
description Formatted string providing the name and version of the model document. The format speficication is "[name]-[version].[subversion]". Each derived model should specifically state the appropriate string for this field.
prefix type ivoa:string
vodml-id dataset.DataModel.prefix
multiplicity 0..1
description Prefix string used in UType string for elements associated with the model. For IVOA standard models, this will be a predetermined string (e.g. 'stc' or 'spec'). Extended, or user defined content can specify a unique prefix for their own content.
URL type ivoa:anyURI
vodml-id dataset.DataModel.URL
multiplicity 0..1
description URL pointer to the XML schema associated with the model.

2.2.9 enumeration: DataProductType

vodml-id dataset.DataProductType
description Enumeration identifying the high level classification of a data product.
package dataset
literals
name feature value
CUBE vodml-id dataset.DataProductType.CUBE
description A multidimensional astronomical image of three (3) or more axes.
IMAGE vodml-id dataset.DataProductType.IMAGE
description A two (2) dimensional astronomical image.
PHOTOMETRY vodml-id dataset.DataProductType.PHOTOMETRY
description Dataset with spectral coverage with irregular gaps.
SPECTRUM vodml-id dataset.DataProductType.SPECTRUM
description Dataset where spectral coverage is the primary attribute, in contiguous bins. e.g. a 1D spectrum or a long slit spectrum.
TIMESERIES vodml-id dataset.DataProductType.TIMESERIES
description Dataset presenting some quantity varying as a function of time. A light curve is a typical example of a timeseries dataset.
SED vodml-id dataset.DataProductType.SED
description A spectral energy distribution, an advanced data product often produced by combining data from multiple observations.
VISIBILITY vodml-id dataset.DataProductType.VISIBILITY
description A visibility (radio) dataset. Typically this is instrumental data, and is often a complex object containing multiple files or other substructures. A visibility dataset may contain data with spatial, spectral, time, and polarization information for each measured visibility.
EVENT vodml-id dataset.DataProductType.EVENT
description An event counting dataset (e.g. X-ray). An event dataset may contain data with spatial, spectral, and time information for each measured event.
CATALOG vodml-id dataset.DataProductType.CATALOG
description A catalog.

2.2.10 objectType: Dataset

vodml-id dataset.Dataset
description Abstract object for the generic IVOA Dataset. It is intended to be useful for any type of data. Specific dataset models should extend this object, providing detailed definitions and additional content as appropriate for that type of dataset.
package dataset
Subclasses in this model ObsDataset
attributes
name feature value
dataProductType type DataProductType [ds:dataset.DataProductType]
vodml-id dataset.Dataset.dataProductType
multiplicity 1
description Describes the high level scientific classification of the data content. Values are restricted to the DataProductType enumeration set and convey the general idea of the content and organization of a dataset.
dataProductSubtype type ivoa:string
vodml-id dataset.Dataset.dataProductSubtype
multiplicity 0..1
description Secondary type classification for the dataset. This field is intended to precisely specify the scientific nature of the data product, possibly in terms relevant only to a specific archive or data collection. For example, dataProductType='image' could have associated dataProductSubtype="src.image", "bkg.image", "PixelMask", etc. Values are unrestricted strings.
compositions
name feature value
curation type Curation [ds:dataset.Curation]
vodml-id dataset.Dataset.curation
multiplicity 1
isOrdered false
description Provides metadata related to the entity responsible for the curation of the dataset.
dataID type DataID [ds:dataset.DataID]
vodml-id dataset.Dataset.dataID
multiplicity 1
isOrdered false
description DataID provides high level identification metadata for the dataset itself, and any associations with various collections.

2.2.11 objectType: Publication

vodml-id dataset.Publication
description Any referenceable publication associated with a Dataset.
package dataset
attributes
name feature value
refCode type ivoa:string
vodml-id dataset.Publication.refCode
multiplicity 1
description Reference code of the publication. Values should be expressed as a URL, or bibcode (discernible as a 19 character string beginning with 4 digits). Free text references are allowed, but discouraged.

2.2.12 objectType: Publisher

vodml-id dataset.Publisher
description Publisher is modeled as a Role played by the organization or entity making the Dataset available.
package dataset
extends Role [ds:party.Role]
attributes
name feature value
publisherID type ivoa:anyURI
vodml-id dataset.Publisher.publisherID
multiplicity 0..1
description IVOA resource identifier associated with the publisher and registered with an IVOA compliant registry (eg: ivo://mast.stsci.edu). Values are to be expressed using the syntax described in "IVOA Identifiers".

2.2.13 enumeration: RightsType

vodml-id dataset.RightsType
description Enumeration of access rights levels.
package dataset
literals
name feature value
PUBLIC vodml-id dataset.RightsType.PUBLIC
description unrestricted, public access is allowed, without authentication.
PROPRIETARY vodml-id dataset.RightsType.PROPRIETARY
description only proprietary access is allowed with authentication.
SECURE vodml-id dataset.RightsType.SECURE
description authenticated, public access is allowed.

2.2.14 enumeration: SpectralBandType

vodml-id dataset.SpectralBandType
description TODO : Missing description : please, update your UML model asap.
package dataset
literals
name feature value
RADIO vodml-id dataset.SpectralBandType.RADIO
description λ ≥ 10 mm; ν ≤ 30 GHz
MILLIMETER vodml-id dataset.SpectralBandType.MILLIMETER
description 0.1 mm ≤ λ ≤ 10 mm; 3000 GHz ≥ ν ≥ 30 GHz
INFRARED vodml-id dataset.SpectralBandType.INFRARED
description 1 μ ≤ λ ≤ 100 μ
OPTICAL vodml-id dataset.SpectralBandType.OPTICAL
description 0.3 μ ≤ λ ≤ 1 μ
ULTRAVIOLET vodml-id dataset.SpectralBandType.ULTRAVIOLET
description 100 Å ≤ λ ≤ 3000 Å; 1.2 eV ≤ E ≤ 120 eV
XRAY vodml-id dataset.SpectralBandType.XRAY
description 0.1 Å ≤ λ ≤ 100 Å; 0.12 keV ≤ E ≤ 120 keV
GAMMARAY vodml-id dataset.SpectralBandType.GAMMARAY
description E ≥ 120keV

2.3 package: experiment

vodml-id experiment
description The Observation Experiment model refers to several elements related to an Observation and its configuration. As of the time of this writing, there is no IVOA recommendation for a general Observation data model. The Provenance data model, in progress, will define the pattern for describing the relation between actions and results, and how to record these in datasets. In lieu of these standards, this document defines a straw-man Observation model.
parent ds
Object types AstroTarget BaseTarget Derived DerivedElement DerivedScalar Facility Instrument ObsConfig ObsDataset Observation Proposal Target

2.3.1 objectType: AstroTarget

vodml-id experiment.AstroTarget
description Extension of BaseTarget specialized for astronomical objects. The AstroTarget defines additional astronomical properties of the target.
package experiment
extends BaseTarget [ds:experiment.BaseTarget]
attributes
name feature value
objectClass type ivoa:string
vodml-id experiment.AstroTarget.objectClass
multiplicity 0..1
description General classification or type of the target. This field supports the discovery of data pertaining to a common class. e.g. "Star", "Galaxy", "AGN". At the time of this writing, there is no IVOA recommended vocabulary for this field. The SIMBAD and NED databases use defined vocabularies for astronomical object classifications which may serve as the basis for such.
spectralClass type ivoa:string
vodml-id experiment.AstroTarget.spectralClass
multiplicity 0..1
description Spectral class of the object. As with objectClass, there is no IVOA recommended vocabulary for specifying the spectral class of an object. There is an IVOA Note on the subject entitled "An encoding system to represent stellar spectral classes in archival databases and catalogs", describing an encoding system which has been adopted by the MAST archive.
redshift type ivoa:real
vodml-id experiment.AstroTarget.redshift
multiplicity 0..1
description This field gives the canonical redshift of the astronomical object. It is normally used to store the cosmological redshift of extragalactic objects, although it may also be used to store the observed redshift of Galactic sources if that information is felt by the data provider to be useful.
varAmpl type ivoa:real
vodml-id experiment.AstroTarget.varAmpl
multiplicity 0..1
description Canonical variability amplitude attributed to the target.

2.3.2 objectType: BaseTarget

vodml-id experiment.BaseTarget
description Abstract base class for the Target object tree. The target object provides identifying metadata related to the subject or goal of the experiment. For an Observational experiment, this would typically be an astronomical object. The BaseTarget class defines high-level identifying information, and must be extended for particular classes of Target which may define additional characteristics.
package experiment
Subclasses in this model AstroTarget Target
referrers ObsDataset
attributes
name feature value
name type ivoa:string
vodml-id experiment.BaseTarget.name
multiplicity 1
description The target name. The primary purpose of this field is to provide the user with a recognizable identity of the particular subject or goal. However, since this may be a query-able field in data discovery protocols, care should be taken to use values which follow conventions for the domain appropriate for the data. For an astronomical object, this may be a name suitable for use within a domain-specific resolution service. Simulated data might also use this sort of name (if simulating a particular object), or a more generic term such as "G2V star".
description type ivoa:string
vodml-id experiment.BaseTarget.description
multiplicity 0..1
description Free form description of target.
references
name feature value
position type meas:Position
vodml-id experiment.BaseTarget.position
multiplicity 0..1
description TODO : Missing description : please, update your UML model asap.

2.3.3 objectType: Derived

vodml-id experiment.Derived
description The Derived (short for Derived Data) object holds derived information obtained by evaluating or analyzing the contents of the dataset. The specific content of this object is strongly dependent on the specific type of dataset, so we provide a generic model which may be specialized in other models to define elements appropriate for that type of dataset. The primary purpose of this object is to provide a common framework in which specific information may be placed to aid in discovery and filtering of datasets in various access protocols.
package experiment
compositions
name feature value
derivedElement type DerivedElement [ds:experiment.DerivedElement]
vodml-id experiment.Derived.derivedElement
multiplicity 0..*
isOrdered false
description Collection of zero or more DerivedElement objects, each of which provides a specific quantity obtained by analyzing the dataset content.

2.3.4 objectType: DerivedElement

vodml-id experiment.DerivedElement
description Abstract base for defining derived data elements. Typically, models for specific data products would extend this object to define various elements appropriate for that model. For example, the Spectrum model could define signal-to-noise ratio (SNR), or TimeSeries could define period, or variability. We put no restriction on the DerivedElement content since the result could be a simple value or a complex object. However, it is recommended that extensions be simple and compact in keeping with the primary intent of use in data discovery.
package experiment
Subclasses in this model DerivedScalar

2.3.5 objectType: DerivedScalar

vodml-id experiment.DerivedScalar
description Simple extension of DerivedElement class which can serve many use cases. Usages of this object in other models to define specific elements should explicitly define the element name, and the process by which the value is determined.
package experiment
extends DerivedElement [ds:experiment.DerivedElement]
attributes
name feature value
name type ivoa:string
vodml-id experiment.DerivedScalar.name
multiplicity 1
description Name identifying the derived element.
value type ivoa:Quantity
vodml-id experiment.DerivedScalar.value
multiplicity 1
description Value of the derived element.

2.3.6 objectType: Facility

vodml-id experiment.Facility
description Facility performing the observation.
package experiment
extends Role [ds:party.Role]
constraints
party.Role.party:Organization[1]

2.3.7 objectType: Instrument

vodml-id experiment.Instrument
description Identifies the instrument used to create the data. This can be a specific instrument name, general type or something else, such as a program in the case of theoretical data. (RM:Collection.Instrument)
package experiment
attributes
name feature value
name type ivoa:string
vodml-id experiment.Instrument.name
multiplicity 1
description Name of the instrument.

2.3.8 objectType: ObsConfig

vodml-id experiment.ObsConfig
description ObsConfig describes all Observation Configuration metadata. We define a small set of configuration elements which are required as Provenance in the observation dataset.
package experiment
referrers ObsDataset
attributes
name feature value
bandpass type ivoa:string
vodml-id experiment.ObsConfig.bandpass
multiplicity 0..1
description Describes the spectral domain of the observation in a very general sense. The value may be expressed in terms of general spectral bands, or specific bandpass names. If multiple bands are covered, the value may be a comma delimited combination of appropriate bands. If expressed as general bands, the value(s) must be selected from the enumerated set given by the SpectralBand type. There is no controlled vocabulary for specific bandpass names as the list is too long to enumerate. Effort should be made to use highly recognized bandpass names (eg: "U","V","B","R","I", "H-alpha"). This field corresponds to both the Coverage.Spectral and Coverage.Spectral.Bandpass fields of the Resource Metadata document.
datasource type ivoa:string
vodml-id experiment.ObsConfig.datasource
multiplicity 0..1
description Describes the original source of the data in a very general fashion. In other words, "What sort of observation originally generated the data?" Suggested values include: + survey: Survey data typically covers some region of observational parameter space with as complete as possible coverage within that region. + pointed: Pointed data of a particular object or field. + theory: Theory data, generated based on a theoretical model. + artificial: Artificial, or simulated data. Similar to 'theory', but not necessarily based on a theoretical model. + custom: Custom data, as part of a specific research project.
compositions
name feature value
facility type Facility [ds:experiment.Facility]
vodml-id experiment.ObsConfig.facility
multiplicity 0..1
isOrdered false
description Metadata pertaining to the facility performing the observation.
instrument type Instrument [ds:experiment.Instrument]
vodml-id experiment.ObsConfig.instrument
multiplicity 0..1
isOrdered false
description Metadata pertaining to the instrument used to create the data.

2.3.9 objectType: ObsDataset

vodml-id experiment.ObsDataset
description Abstract object extending Dataset with metadata relevant to datasets derived from Observations.
package experiment
extends Dataset [ds:dataset.Dataset]
attributes
name feature value
calibLevel type ivoa:integer
vodml-id experiment.ObsDataset.calibLevel
multiplicity 0..1
description High level classification for the calibration level of the particular dataset as a whole. The calibration level concept conveys to the user information on how much data reduction/processing has been applied to the data. It is up to the data providers to consider how to map their own internal classification to the scale defined here. Scale: * 0 - Raw instrumental data, in a proprietary or internal data-provider defined format. * 1 - Instrumental data in a standard format (FITS, VOTable, etc ) * 2 - Calibrated, science ready data with the instrument signature removed. * 3 - Enhanced data products like mosaics, resampled or drizzled images, or heavily processed survey fields. Level 3 data products may represent the combination of data from multiple primary observations.
references
name feature value
obsConfig type ObsConfig [ds:experiment.ObsConfig]
vodml-id experiment.ObsDataset.obsConfig
multiplicity 0..1
description Reference to ObsConfig object from Observation. This object provides some high-level metadata related to the observation configuration.
proposal type Proposal [ds:experiment.Proposal]
vodml-id experiment.ObsDataset.proposal
multiplicity 0..1
description Reference to Proposal object from Observation. This object provides metadata identifying any proposal related to the observation which produced the dataset.
target type BaseTarget [ds:experiment.BaseTarget]
vodml-id experiment.ObsDataset.target
multiplicity 1
description Reference to a BaseTarget object from Observation. Provides metadata describing the target of the observation.
compositions
name feature value
derived type Derived [ds:experiment.Derived]
vodml-id experiment.ObsDataset.derived
multiplicity 0..1
isOrdered false
description Provides a high level summary of certain properties of the dataset. Its primary purpose is to support high level filtering of datasets during data discovery.

2.3.10 objectType: Observation

vodml-id experiment.Observation
description Head class for an Observation Experiment. The Observation is modeled as a type of 'Experiment', with some basic structure defined to provide metadata about the observation target and configuration. The product, or 'result' of the Observation is zero or more ObsDataset objects. This pattern is inspired by, and compatible with the Simulation Data Model, where a 'Simulation' can be considered another form of 'Experiment' or perhaps even another form of 'Observation'.
package experiment
attributes
name feature value
observationID type ivoa:string
vodml-id experiment.Observation.observationID
multiplicity 1
description Internal ID determined by the data provide to uniquely identify the observation within the institution or entity performing the observation.
compositions
name feature value
obsConfig type ObsConfig [ds:experiment.ObsConfig]
vodml-id experiment.Observation.obsConfig
multiplicity 1
isOrdered false
description Observation configuration metadata, provides information about who, where, and how the observation was conducted.
proposal type Proposal [ds:experiment.Proposal]
vodml-id experiment.Observation.proposal
multiplicity 0..1
isOrdered false
description Identifies any proposal related to the observation. This field may be used to gather all observations and products related to a particular proposal.
result type ObsDataset [ds:experiment.ObsDataset]
vodml-id experiment.Observation.result
multiplicity 0..*
isOrdered false
description The result of an observation is zero or more Observation Datasets.
target type BaseTarget [ds:experiment.BaseTarget]
vodml-id experiment.Observation.target
multiplicity 1
isOrdered false
description The target of the observation. The content of this object may vary greatly depending on the goals and nature of the observation. For example, the 'target' could be a galaxy, stellar object, planet, or calibratioin source. As such, we allow the BaseTarget class here, and permit the users to define and use more content rich flavors according to their needs.

2.3.11 objectType: Proposal

vodml-id experiment.Proposal
description Metadata related to the proposal or document which spawned the observation.
package experiment
referrers ObsDataset
attributes
name feature value
identifier type ivoa:string
vodml-id experiment.Proposal.identifier
multiplicity 1
description Tag used to uniquely identify a particular proposal within the institution or entity.

2.3.12 objectType: Target

vodml-id experiment.Target
description General purpose Target object.
package experiment
extends BaseTarget [ds:experiment.BaseTarget]
attributes
name feature value
objectClass type ivoa:string
vodml-id experiment.Target.objectClass
multiplicity 0..1
description General classification or type of the target. This field supports the discovery of data pertaining to a common class. e.g. "Star", "Galaxy", "AGN". At the time of this writing, there is no IVOA recommended vocabulary for this field. The SIMBAD and NED databases use defined vocabularies for astronomical object classifications which may serve as the basis for such.

2.4 package: party

vodml-id party
description We include a simple Party model for associating an Entity with a Role that Entity is playing. For example, a particular Individual can be both a Contact and Publisher of a dataset.
parent ds
Object types Individual Organization Party Role

2.4.1 objectType: Individual

vodml-id party.Individual
description Abstract head of the sub-set of Parties which describe a single individual.
package party
extends Party [ds:party.Party]
attributes
name feature value
address type ivoa:string
vodml-id party.Individual.address
multiplicity 0..1
description Mailing address for the person. The value is expressed as a single string containing all components of the address.
phone type ivoa:string
vodml-id party.Individual.phone
multiplicity 0..1
description Phone number associated with the person. The value is expressed as a string according to the format appropriate for the locale.
email type ivoa:string
vodml-id party.Individual.email
multiplicity 0..1
description E-mail address of the Individual

2.4.2 objectType: Organization

vodml-id party.Organization
description Extension of Party for any Organization or Institution.
package party
extends Party [ds:party.Party]
attributes
name feature value
address type ivoa:string
vodml-id party.Organization.address
multiplicity 0..1
description Mailing address. The value is expressed as a single string containing all components of the address.
phone type ivoa:string
vodml-id party.Organization.phone
multiplicity 0..1
description Phone number. The value is expressed as a string according to the format appropriate for the locale.
email type ivoa:string
vodml-id party.Organization.email
multiplicity 0..1
description E-mail address of the Organization.
logo type ivoa:anyURI
vodml-id party.Organization.logo
multiplicity 0..1
description URL pointer to a graphical logo associated with the Organization.

2.4.3 objectType: Party

vodml-id party.Party
description Abstract head of the set of classes describing various entities.
package party
Subclasses in this model Individual Organization
referrers Role
attributes
name feature value
name type ivoa:string
vodml-id party.Party.name
multiplicity 1
description Name of the Party or entity. All entities are assumed to have a name.

2.4.4 objectType: Role

vodml-id party.Role
description Abstract class for the entity role. Models should extend this class to define local roles which are played by various entities/parties.
package party
Subclasses in this model Contact Contributor Creator Facility Publisher
references
name feature value
party type Party [ds:party.Party]
vodml-id party.Role.party
multiplicity 1
description Reference to the Party or Entity which is associated with this role.


3.Element Identifiers/VO-DMLrefs

The following table shows all fully qualified vodml-ids for this data model. It is ordered alphabetically and the identifiers are hyper-linked to the location in the document where the actual element is fully defined.
vodml-id feature type description
vo-dml:model This document provides a data model describing the structure and content of generic Dataset metadata for the IVOA. This is a high-level model which is to be referenced and extended by other models describing specific types of Datasets and Data products. In this document, we specify the generic Dataset, as well as an ObservationDataset model which covers the class of Datasets which are derived from an Observation. At the time of this writing, there is no formal Observation-Experiment model for the IVOA, so we include a hypothetical Observation-Experiment model to serve as a placeholder.
dataset package Dataset Metadata package
dataset.Collection objectType A generic organizational construct which allows Datasets to be associated with each other by a set of Collection properties. Datasets tagged with the same Collection properies can be assumed to have some degree of compatibility.
dataset.Collection.name attribute The values are generally defined by the creating entity. Examples: "WFC", "Sloan", "BFS Spectrograph", "MSX Galactic Plane Survey".
dataset.Contact objectType Contact information for a person or entity. Contact is modeled as a Role played by a particular person or entity (Party). We subset the type of Party to include only Individuals. This includes both a physical person, or proxy service such as a helpdesk.
dataset.Contributor objectType Contributor is modeled as a Role played by a Party or entity who participated in the generation of the Dataset.
dataset.Contributor.acknowledgment attribute Acknowledgment expression for the contributor. Users of the dataset should include these in subsequent credits and acknowledgements. The expression should be formatted as desired by the contributor.
dataset.CreationType enumeration Enumeration of dataset creation types.
dataset.CreationType.ARCHIVAL literal Indicates that it is one of a collection of datasets generated in a systematic, homogeneous way and is stored statically (or at least versioned). It will be possible to regenerate this dataset at a later date. The remaining types imply on-the-fly manipulation.
dataset.CreationType.CATALOG_EXTRACTION literal Has been extracted from a catalog.
dataset.CreationType.CUTOUT literal Indicates that the dataset was created "on-the-fly", by subsetting, but not by modifying values.
dataset.CreationType.FILTERED literal May involve excluding data prior to binning into samples, also "on-the-fly"
dataset.CreationType.MOSAIC literal Combines multiple original datasets "on-the-fly"
dataset.CreationType.SPECTRAL_EXTRACTION literal Has been extracted, for example, from a spectral data cube.
dataset.Creator objectType Creator is modeled as a Role played by the organization or entity which created the Dataset.
dataset.Curation objectType The Curation object provides metadata assigned by the entity responsible for the support of the dataset content as well as identifying metadata about that entity. It is assembled from definitions provided by the IVOA standard document, "Resource Metadata for the Virtual Observatory; Version 1.12" (Resource Metadata). Here, we provide a brief description of each field for easy reference, along with a notation of its mapping to the Resource Metadata document (RM:field), where the reader may find more detailed information.
dataset.Curation.contact composition Contact information of the person/entity responsible for the content of the dataset. We recommend using a generic 'helpdesk' type contact rather than individuals whose information may more easily become obsolete. (RM:Curation.Contact)
dataset.Curation.publisher composition The entity making the data available. (RM:Curation.Publisher)
dataset.Curation.publisherDID attribute IVOA dataset identifier assigned by the publisher to uniquely identify the dataset within its holdings. Typically, the basis of this identifier will be the publisher ID. However, if the publisherchooses to use a 'global index service' such as ADS to obtain persistent identifiers for their datasets, rather than generate their own, that identifier should be used both here and for DataID.datasetID. Note: this model also defines a creator dataset ID (DataID.creatorDID), these will differ if the publishing entity is not the creator of the dataset. Values are to be expressed as dataset identifiers using the syntax described in "IVOA Identifiers"
dataset.Curation.reference composition Zero or more bibliographic or documentation references associated with the dataset. Each instance provides a single forward link to a major publication which references the dataset. (RM:General.Source)
dataset.Curation.releaseDate attribute Date the curated dataset was last modified. (RM:Curation.Date)
dataset.Curation.rights attribute TODO : Missing description : please, update your UML model asap.
dataset.Curation.version attribute Version of the curated dataset, assigned by the publisher. This is an independent versioning from DataID.version that allows the publisher to track changes to the high level dataset metadata (e.g. curation metadata, identifiers, etc.) without effecting the creator defined dataset version. The value may be based on the DataID.version (e.g. by adding a sub-version extension), or an independent versioning. There are no format restrictions on the value. (RM:Curation.Version)
dataset.DataID objectType The Data Identification object (DataID) stores the dataset identifiers and other metadata typically assigned by the dataset creator. The Dataset IDs in this object must comply with the syntax for dataset identifiers defined in the "IVOA Identifiers" document, including the use of 'stop' characters to identify specific datasets that are not individually in the registry. e.g., ivo://example.net/aservice?2013/5/2342. Much of the content of this object is assembled from various definitions in the IVAO Resource Metadata document. Here, we provide a brief description of each field for easy reference, along with a notation of its mapping to the Resource Metadata document (RM:field), where the reader may find more detailed information.
dataset.DataID.collection composition The dataset is associated with zero or more Collections (instrument name, survey name, etc.) . Each instance identifies a tag indicating some degree of compatibility with other data sharing the same Collection properties.
dataset.DataID.contributor composition Persons or entities who contributed to the generation of the scientific content of the dataset. Users of the dataset should include these in subsequent credits and acknowledgements. (RM:Curation.Contributor)
dataset.DataID.creationType attribute The dataset creation type describes the nature or genre of the content. (RM:General.Type). Note: This field provides information about the process by which the dataset was created. As the Observation/Experiment model matures, this may evolve into a provenance element on the Experiment type.
dataset.DataID.creator composition The institution or entity which created the dataset.
dataset.DataID.creatorDID attribute The dataset identifier assigned by the creator. Here, the authority-id of the identifier must be that of the creator. It is used to identify the original exposure of the dataset in an archive, and will remain static regardless of where the dataset is published. The creator ID will not necessarily change even if the VO object in question is a cutout or is otherwise further processed.
dataset.DataID.datasetID attribute If the dataset is registered with an external 'global index service' such as ADS, the publisher may include that identifier here. This provides a common, persistent identifier for the dataset, and possible access point to follow for information on publications and other related datasets. Note: the same dataset published at more than one location would have different Curation.publisherDID values, but the same DataID.datasetID. eg: "ivo://ADS/Sa.CXO?obsid=1234", "ivo://ADS/sh.hut#ngc4151_141"
dataset.DataID.date attribute Data processing or creation date (RM:Curation.Date).
dataset.DataID.title attribute A free form string giving a title for the dataset. (RM:Identity.Title)
dataset.DataID.version attribute Version assigned by the creator, reflecting the production version of the dataset. This value should only be changed by the creator, upon the new release of a dataset. There are no format restrictions or specifications on the versioning scheme.
dataset.DataModel objectType This object provides specific information regarding the data model and version thereof that a dataset represents. This information is primarily an aide to (de)serialization of the dataset. As such, it would better be defined by serialization conventions. In lieu of such conventions, we include this object and representative serialization examples for the primary file formats VOTable and FITS.
dataset.DataModel.URL attribute URL pointer to the XML schema associated with the model.
dataset.DataModel.name attribute Formatted string providing the name and version of the model document. The format speficication is "[name]-[version].[subversion]". Each derived model should specifically state the appropriate string for this field.
dataset.DataModel.prefix attribute Prefix string used in UType string for elements associated with the model. For IVOA standard models, this will be a predetermined string (e.g. 'stc' or 'spec'). Extended, or user defined content can specify a unique prefix for their own content.
dataset.DataProductType enumeration Enumeration identifying the high level classification of a data product.
dataset.DataProductType.CATALOG literal A catalog.
dataset.DataProductType.CUBE literal A multidimensional astronomical image of three (3) or more axes.
dataset.DataProductType.EVENT literal An event counting dataset (e.g. X-ray). An event dataset may contain data with spatial, spectral, and time information for each measured event.
dataset.DataProductType.IMAGE literal A two (2) dimensional astronomical image.
dataset.DataProductType.PHOTOMETRY literal Dataset with spectral coverage with irregular gaps.
dataset.DataProductType.SED literal A spectral energy distribution, an advanced data product often produced by combining data from multiple observations.
dataset.DataProductType.SPECTRUM literal Dataset where spectral coverage is the primary attribute, in contiguous bins. e.g. a 1D spectrum or a long slit spectrum.
dataset.DataProductType.TIMESERIES literal Dataset presenting some quantity varying as a function of time. A light curve is a typical example of a timeseries dataset.
dataset.DataProductType.VISIBILITY literal A visibility (radio) dataset. Typically this is instrumental data, and is often a complex object containing multiple files or other substructures. A visibility dataset may contain data with spatial, spectral, time, and polarization information for each measured visibility.
dataset.Dataset objectType Abstract object for the generic IVOA Dataset. It is intended to be useful for any type of data. Specific dataset models should extend this object, providing detailed definitions and additional content as appropriate for that type of dataset.
dataset.Dataset.curation composition Provides metadata related to the entity responsible for the curation of the dataset.
dataset.Dataset.dataID composition DataID provides high level identification metadata for the dataset itself, and any associations with various collections.
dataset.Dataset.dataProductSubtype attribute Secondary type classification for the dataset. This field is intended to precisely specify the scientific nature of the data product, possibly in terms relevant only to a specific archive or data collection. For example, dataProductType='image' could have associated dataProductSubtype="src.image", "bkg.image", "PixelMask", etc. Values are unrestricted strings.
dataset.Dataset.dataProductType attribute Describes the high level scientific classification of the data content. Values are restricted to the DataProductType enumeration set and convey the general idea of the content and organization of a dataset.
dataset.Publication objectType Any referenceable publication associated with a Dataset.
dataset.Publication.refCode attribute Reference code of the publication. Values should be expressed as a URL, or bibcode (discernible as a 19 character string beginning with 4 digits). Free text references are allowed, but discouraged.
dataset.Publisher objectType Publisher is modeled as a Role played by the organization or entity making the Dataset available.
dataset.Publisher.publisherID attribute IVOA resource identifier associated with the publisher and registered with an IVOA compliant registry (eg: ivo://mast.stsci.edu). Values are to be expressed using the syntax described in "IVOA Identifiers".
dataset.RightsType enumeration Enumeration of access rights levels.
dataset.RightsType.PROPRIETARY literal only proprietary access is allowed with authentication.
dataset.RightsType.PUBLIC literal unrestricted, public access is allowed, without authentication.
dataset.RightsType.SECURE literal authenticated, public access is allowed.
dataset.SpectralBandType enumeration TODO : Missing description : please, update your UML model asap.
dataset.SpectralBandType.GAMMARAY literal E ≥ 120keV
dataset.SpectralBandType.INFRARED literal 1 μ ≤ λ ≤ 100 μ
dataset.SpectralBandType.MILLIMETER literal 0.1 mm ≤ λ ≤ 10 mm; 3000 GHz ≥ ν ≥ 30 GHz
dataset.SpectralBandType.OPTICAL literal 0.3 μ ≤ λ ≤ 1 μ
dataset.SpectralBandType.RADIO literal λ ≥ 10 mm; ν ≤ 30 GHz
dataset.SpectralBandType.ULTRAVIOLET literal 100 Å ≤ λ ≤ 3000 Å; 1.2 eV ≤ E ≤ 120 eV
dataset.SpectralBandType.XRAY literal 0.1 Å ≤ λ ≤ 100 Å; 0.12 keV ≤ E ≤ 120 keV
experiment package The Observation Experiment model refers to several elements related to an Observation and its configuration. As of the time of this writing, there is no IVOA recommendation for a general Observation data model. The Provenance data model, in progress, will define the pattern for describing the relation between actions and results, and how to record these in datasets. In lieu of these standards, this document defines a straw-man Observation model.
experiment.AstroTarget objectType Extension of BaseTarget specialized for astronomical objects. The AstroTarget defines additional astronomical properties of the target.
experiment.AstroTarget.objectClass attribute General classification or type of the target. This field supports the discovery of data pertaining to a common class. e.g. "Star", "Galaxy", "AGN". At the time of this writing, there is no IVOA recommended vocabulary for this field. The SIMBAD and NED databases use defined vocabularies for astronomical object classifications which may serve as the basis for such.
experiment.AstroTarget.redshift attribute This field gives the canonical redshift of the astronomical object. It is normally used to store the cosmological redshift of extragalactic objects, although it may also be used to store the observed redshift of Galactic sources if that information is felt by the data provider to be useful.
experiment.AstroTarget.spectralClass attribute Spectral class of the object. As with objectClass, there is no IVOA recommended vocabulary for specifying the spectral class of an object. There is an IVOA Note on the subject entitled "An encoding system to represent stellar spectral classes in archival databases and catalogs", describing an encoding system which has been adopted by the MAST archive.
experiment.AstroTarget.varAmpl attribute Canonical variability amplitude attributed to the target.
experiment.BaseTarget objectType Abstract base class for the Target object tree. The target object provides identifying metadata related to the subject or goal of the experiment. For an Observational experiment, this would typically be an astronomical object. The BaseTarget class defines high-level identifying information, and must be extended for particular classes of Target which may define additional characteristics.
experiment.BaseTarget.description attribute Free form description of target.
experiment.BaseTarget.name attribute The target name. The primary purpose of this field is to provide the user with a recognizable identity of the particular subject or goal. However, since this may be a query-able field in data discovery protocols, care should be taken to use values which follow conventions for the domain appropriate for the data. For an astronomical object, this may be a name suitable for use within a domain-specific resolution service. Simulated data might also use this sort of name (if simulating a particular object), or a more generic term such as "G2V star".
experiment.BaseTarget.position reference TODO : Missing description : please, update your UML model asap.
experiment.Derived objectType The Derived (short for Derived Data) object holds derived information obtained by evaluating or analyzing the contents of the dataset. The specific content of this object is strongly dependent on the specific type of dataset, so we provide a generic model which may be specialized in other models to define elements appropriate for that type of dataset. The primary purpose of this object is to provide a common framework in which specific information may be placed to aid in discovery and filtering of datasets in various access protocols.
experiment.Derived.derivedElement composition Collection of zero or more DerivedElement objects, each of which provides a specific quantity obtained by analyzing the dataset content.
experiment.DerivedElement objectType Abstract base for defining derived data elements. Typically, models for specific data products would extend this object to define various elements appropriate for that model. For example, the Spectrum model could define signal-to-noise ratio (SNR), or TimeSeries could define period, or variability. We put no restriction on the DerivedElement content since the result could be a simple value or a complex object. However, it is recommended that extensions be simple and compact in keeping with the primary intent of use in data discovery.
experiment.DerivedScalar objectType Simple extension of DerivedElement class which can serve many use cases. Usages of this object in other models to define specific elements should explicitly define the element name, and the process by which the value is determined.
experiment.DerivedScalar.name attribute Name identifying the derived element.
experiment.DerivedScalar.value attribute Value of the derived element.
experiment.Facility objectType Facility performing the observation.
experiment.Instrument objectType Identifies the instrument used to create the data. This can be a specific instrument name, general type or something else, such as a program in the case of theoretical data. (RM:Collection.Instrument)
experiment.Instrument.name attribute Name of the instrument.
experiment.ObsConfig objectType ObsConfig describes all Observation Configuration metadata. We define a small set of configuration elements which are required as Provenance in the observation dataset.
experiment.ObsConfig.bandpass attribute Describes the spectral domain of the observation in a very general sense. The value may be expressed in terms of general spectral bands, or specific bandpass names. If multiple bands are covered, the value may be a comma delimited combination of appropriate bands. If expressed as general bands, the value(s) must be selected from the enumerated set given by the SpectralBand type. There is no controlled vocabulary for specific bandpass names as the list is too long to enumerate. Effort should be made to use highly recognized bandpass names (eg: "U","V","B","R","I", "H-alpha"). This field corresponds to both the Coverage.Spectral and Coverage.Spectral.Bandpass fields of the Resource Metadata document.
experiment.ObsConfig.datasource attribute Describes the original source of the data in a very general fashion. In other words, "What sort of observation originally generated the data?" Suggested values include: + survey: Survey data typically covers some region of observational parameter space with as complete as possible coverage within that region. + pointed: Pointed data of a particular object or field. + theory: Theory data, generated based on a theoretical model. + artificial: Artificial, or simulated data. Similar to 'theory', but not necessarily based on a theoretical model. + custom: Custom data, as part of a specific research project.
experiment.ObsConfig.facility composition Metadata pertaining to the facility performing the observation.
experiment.ObsConfig.instrument composition Metadata pertaining to the instrument used to create the data.
experiment.ObsDataset objectType Abstract object extending Dataset with metadata relevant to datasets derived from Observations.
experiment.ObsDataset.calibLevel attribute High level classification for the calibration level of the particular dataset as a whole. The calibration level concept conveys to the user information on how much data reduction/processing has been applied to the data. It is up to the data providers to consider how to map their own internal classification to the scale defined here. Scale: * 0 - Raw instrumental data, in a proprietary or internal data-provider defined format. * 1 - Instrumental data in a standard format (FITS, VOTable, etc ) * 2 - Calibrated, science ready data with the instrument signature removed. * 3 - Enhanced data products like mosaics, resampled or drizzled images, or heavily processed survey fields. Level 3 data products may represent the combination of data from multiple primary observations.
experiment.ObsDataset.derived composition Provides a high level summary of certain properties of the dataset. Its primary purpose is to support high level filtering of datasets during data discovery.
experiment.ObsDataset.obsConfig reference Reference to ObsConfig object from Observation. This object provides some high-level metadata related to the observation configuration.
experiment.ObsDataset.proposal reference Reference to Proposal object from Observation. This object provides metadata identifying any proposal related to the observation which produced the dataset.
experiment.ObsDataset.target reference Reference to a BaseTarget object from Observation. Provides metadata describing the target of the observation.
experiment.Observation objectType Head class for an Observation Experiment. The Observation is modeled as a type of 'Experiment', with some basic structure defined to provide metadata about the observation target and configuration. The product, or 'result' of the Observation is zero or more ObsDataset objects. This pattern is inspired by, and compatible with the Simulation Data Model, where a 'Simulation' can be considered another form of 'Experiment' or perhaps even another form of 'Observation'.
experiment.Observation.obsConfig composition Observation configuration metadata, provides information about who, where, and how the observation was conducted.
experiment.Observation.observationID attribute Internal ID determined by the data provide to uniquely identify the observation within the institution or entity performing the observation.
experiment.Observation.proposal composition Identifies any proposal related to the observation. This field may be used to gather all observations and products related to a particular proposal.
experiment.Observation.result composition The result of an observation is zero or more Observation Datasets.
experiment.Observation.target composition The target of the observation. The content of this object may vary greatly depending on the goals and nature of the observation. For example, the 'target' could be a galaxy, stellar object, planet, or calibratioin source. As such, we allow the BaseTarget class here, and permit the users to define and use more content rich flavors according to their needs.
experiment.Proposal objectType Metadata related to the proposal or document which spawned the observation.
experiment.Proposal.identifier attribute Tag used to uniquely identify a particular proposal within the institution or entity.
experiment.Target objectType General purpose Target object.
experiment.Target.objectClass attribute General classification or type of the target. This field supports the discovery of data pertaining to a common class. e.g. "Star", "Galaxy", "AGN". At the time of this writing, there is no IVOA recommended vocabulary for this field. The SIMBAD and NED databases use defined vocabularies for astronomical object classifications which may serve as the basis for such.
party package We include a simple Party model for associating an Entity with a Role that Entity is playing. For example, a particular Individual can be both a Contact and Publisher of a dataset.
party.Individual objectType Abstract head of the sub-set of Parties which describe a single individual.
party.Individual.address attribute Mailing address for the person. The value is expressed as a single string containing all components of the address.
party.Individual.email attribute E-mail address of the Individual
party.Individual.phone attribute Phone number associated with the person. The value is expressed as a string according to the format appropriate for the locale.
party.Organization objectType Extension of Party for any Organization or Institution.
party.Organization.address attribute Mailing address. The value is expressed as a single string containing all components of the address.
party.Organization.email attribute E-mail address of the Organization.
party.Organization.logo attribute URL pointer to a graphical logo associated with the Organization.
party.Organization.phone attribute Phone number. The value is expressed as a string according to the format appropriate for the locale.
party.Party objectType Abstract head of the set of classes describing various entities.
party.Party.name attribute Name of the Party or entity. All entities are assumed to have a name.
party.Role objectType Abstract class for the entity role. Models should extend this class to define local roles which are played by various entities/parties.
party.Role.party reference Reference to the Party or Entity which is associated with this role.

4.Imported Models

This section lists the external models imported by the current data model. For each imported model we list URLs to the VO-DML and HTML representations and the prefix used for vodml-ids from inside the model.

4.1 ivoa

Model vodml-id ivoa
url http://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/ivoa/IVOA.vo-dml.xml
documentation url http://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/ivoa/IVOA.html

4.2 meas

Model vodml-id meas
url https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/STC2/prototype/meas/STCMeas-2.0.vo-dml.xml
documentation url https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/STC2/prototype/meas/STCMeas-2.0.html