PhotDM

Table of Contents

1.     model: Phot
2.     Packages and Types
2.1     [root package]
2.1.1     objectType:Access
2.1.2     objectType:AsinhZeropoint
2.1.3     objectType:Bandwidth
2.1.4     objectType:Flux
2.1.5     objectType:LinearFluxZeropoint
2.1.6     objectType:MagnitudeSystem
2.1.7     objectType:PhotCal
2.1.8     objectType:PhotometricSystem
2.1.9     objectType:PhotometryFilter
2.1.10     objectType:PogsonZeropoint
2.1.11     objectType:SpectralLocation
2.1.12     objectType:TransmissionCurve
2.1.13     objectType:TransmissionPoint
2.1.14     enumeration:TypeOfMagSystem
2.1.15     primitiveType:UCD
2.1.16     objectType:ZeroPoint
3.     vodml-id-s
4.     Imported Models
4.1     ivoa

1. Model: PhotDM (Phot)

Authors : Jesús Salgado, Carlos Rodrigo, Pedro Osuna, Mark Allen, Mireille Louys, Jonathan McDowell, Deborah Baines, Jesús Maíz Apellániz, Evanthia Hatziminaoglou, Sebastien Derriere, Gerard Lemson
Date : 2021-04-19T16:14:18
Version : 1.1
Previous version: : 1.0
Abstract : Data model describing data sets Photometric properties and used for data calibration, comparison or reprocessing.
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 Phot
Object types Access AsinhZeropoint Bandwidth Flux LinearFluxZeropoint MagnitudeSystem PhotCal PhotometricSystem PhotometryFilter PogsonZeropoint SpectralLocation TransmissionCurve TransmissionPoint ZeroPoint
Enumerations TypeOfMagSystem
Primitive types UCD

2.1.1 objectType: Access

vodml-id Access
description Gathers all properties to access a resource : uri, format and size .
attributes
name feature value
reference type ivoa:anyURI
vodml-id Access.reference
multiplicity 1
description URI to access the resource.
size type ivoa:integer
vodml-id Access.size
multiplicity 1
description Approximate estimated size of the dataset, specified in kilobytes.
format type ivoa:string
vodml-id Access.format
multiplicity 1
description Format of the accessed resource. typically : application/fits, application/x-votable+xml, text/csv, text/xml.

2.1.2 objectType: AsinhZeropoint

vodml-id AsinhZeropoint
description Extension of ZeroPoint to describe asinh magnitudes, a.k.a. luptitudes.
extends ZeroPoint [Phot:ZeroPoint]
attributes
name feature value
softeningParameter type ivoa:real
vodml-id AsinhZeropoint.softeningParameter
multiplicity 1
description Parameter used to correct the calculation of magnitudes for faint sources. Usually called 'b'. See (Lupton and Gunn et al. [1999]) for a formal explanation.

2.1.3 objectType: Bandwidth

vodml-id Bandwidth
description This class is used to characterize the spectral properties of a filter.
attributes
name feature value
ucd type UCD [Phot:UCD]
vodml-id Bandwidth.ucd
multiplicity 1
description Unified Content Description (UCD) string that specifies the nature of the bandwidth object.
unitexpression type ivoa:Unit
vodml-id Bandwidth.unitexpression
multiplicity 1
description Unit string that specifies the spectral units for this filter.
extent type ivoa:real
vodml-id Bandwidth.extent
multiplicity 0..1
description Bandwidth’s extent of the filter , as length of the covered spectral interval , or effective width following appropriate filter type.
start type ivoa:real
vodml-id Bandwidth.start
multiplicity 1
description In practice, this could be taken as the minimum value of the filter transmission curve.
stop type ivoa:real
vodml-id Bandwidth.stop
multiplicity 1
description In practice, this could be taken as the maximum value of the filter transmission curve.
constraints
One association at the time

2.1.4 objectType: Flux

vodml-id Flux
description This class is used to characterize the spectral properties of a filter.
attributes
name feature value
ucd type UCD [Phot:UCD]
vodml-id Flux.ucd
multiplicity 1
description Unified Content Description (UCD) string that specifies the nature of the spectral location for this filter.
unitexpression type ivoa:Unit
vodml-id Flux.unitexpression
multiplicity 1
description Unit string that specifies the spectral units for this filter.
value type ivoa:real
vodml-id Flux.value
multiplicity 1
description A spectral coordinate value that can be considered by the data provider as the most representative for this specific filter bandpass. as an example effective wavelength in optical.
error type ivoa:real
vodml-id Flux.error
multiplicity 1
description Flux value error corresponding to the reference magnitude value of the calibrating object.
constraints
One association at the time

2.1.5 objectType: LinearFluxZeropoint

vodml-id LinearFluxZeropoint
description Extension of ZeroPoint to describe simple linear flux photometry, commonly used in Radio, Far Infrared and X-ray spectral ranges. Although not being magnitudes as such, relative linear flux measurements can be included as a special and trivial case of magnitude.
extends ZeroPoint [Phot:ZeroPoint]

2.1.6 objectType: MagnitudeSystem

vodml-id MagnitudeSystem
description A class to describe the Magnitude system, the reference spectrum attached and the type .
attributes
name feature value
type type TypeOfMagSystem [Phot:TypeOfMagSystem]
vodml-id MagnitudeSystem.type
multiplicity 1
description Type of magnitude system used to compute the the associated zeropoint . Typical values are : VEGAmag, ABmag, STmag .
referenceSpectrum type ivoa:anyURI
vodml-id MagnitudeSystem.referenceSpectrum
multiplicity 1
description Link to the reference spectrum as a URI.

2.1.7 objectType: PhotCal

vodml-id PhotCal
description A class to bind together all photometic calibration reference information: a photometry filter, a certain magnitude system configuration and a certain zero point object.
attributes
name feature value
identifier type ivoa:string
vodml-id PhotCal.identifier
multiplicity 1
description A unique identifier of the Photometry calibration intance within the project and a filterprofile service . Suggested syntax would be: Facility/Subcategory/Band/Photometric System Type[/Suffix]
references
name feature value
photometryFilter type PhotometryFilter [Phot:PhotometryFilter]
vodml-id PhotCal.photometryFilter
multiplicity 0..1
description Each Photcal element is related to one single Filter .
compositions
name feature value
magnitudeSystem type MagnitudeSystem [Phot:MagnitudeSystem]
vodml-id PhotCal.magnitudeSystem
multiplicity 1
isOrdered false
description Each ZeroPoint values are given with one computation method corresponding to a defined Magnitude system.
zeroPoint type ZeroPoint [Phot:ZeroPoint]
vodml-id PhotCal.zeroPoint
multiplicity 1
isOrdered false
description The ZeroPoint values for the flux to mag translation belongs to a Photcal element and is defined for one Filter element and one MagnitudeSystem .
constraints
One association at the time

2.1.8 objectType: PhotometricSystem

vodml-id PhotometricSystem
description The reference photometric system used to interpret photometic measurements.
attributes
name feature value
description type ivoa:string
vodml-id PhotometricSystem.description
multiplicity 1
description This string contains a human readable short-text representation of the photometric system. This will allow client applications to display textual information to final users.
detectorType type ivoa:integer
vodml-id PhotometricSystem.detectorType
multiplicity 1
description Detector type associated to this photometric system. Possible values are: 0 for Energy counter ( amplifiers ), 1 for Photon counter ( CCDs, Photomultipliers).
compositions
name feature value
photometryFilter type PhotometryFilter [Phot:PhotometryFilter]
vodml-id PhotometricSystem.photometryFilter
multiplicity 1..*
isOrdered false
description The Photometric information is related to a Photometric system, and gathers filter descriptions, for one or several .
constraints
One association at the time

2.1.9 objectType: PhotometryFilter

vodml-id PhotometryFilter
description The reference photometric system used to interpret photometic measurements.
referrers PhotCal
attributes
name feature value
fpsidentifier type ivoa:string
vodml-id PhotometryFilter.fpsidentifier
multiplicity 1
description IVOA identifier of the filter profile service where this photometry filter is registered to be used in the discovery of all the relevant photometry filter properties.
identifier type ivoa:string
vodml-id PhotometryFilter.identifier
multiplicity 1
description This field identifies, in a unique way, within a certain Photometry Filter Profile service, a filter. example : Facility/Subcategory/Band[/Suffix] like SDSS/SDSS.G/G
name type ivoa:string
vodml-id PhotometryFilter.name
multiplicity 1
description A human readable string to represent the filter name.
description type ivoa:string
vodml-id PhotometryFilter.description
multiplicity 1
description This string contains a verbose human readable label for the filter. This will allow client applications to display textual information to final users.
bandname type ivoa:string
vodml-id PhotometryFilter.bandname
multiplicity 1
description A standard label representing of the spectral band associated to this filter (if any).
dateValidityFrom type ivoa:datetime
vodml-id PhotometryFilter.dateValidityFrom
multiplicity 1
description Start time of the time coverage when this filter configuration is applicable. String time format accepted is ISO8601.
dateValidityTo type ivoa:datetime
vodml-id PhotometryFilter.dateValidityTo
multiplicity 1
description End time of the time coverage when this filter configuration is applicable. String time format accepted is ISO8601.
compositions
name feature value
bandwidth type Bandwidth [Phot:Bandwidth]
vodml-id PhotometryFilter.bandwidth
multiplicity 1
isOrdered false
description Relation to the spectral coverage of the Filter.
spectralLocation type SpectralLocation [Phot:SpectralLocation]
vodml-id PhotometryFilter.spectralLocation
multiplicity 1
isOrdered false
description TODO : Missing description : please, update your UML model asap.
transmissionCurve type TransmissionCurve [Phot:TransmissionCurve]
vodml-id PhotometryFilter.transmissionCurve
multiplicity 0..1
isOrdered false
description Link to the Transmission Curve of the Filter, when this is described.
constraints
One association at the time

2.1.10 objectType: PogsonZeropoint

vodml-id PogsonZeropoint
description Extension of ZeroPoint to accommodate standard logarithm magnitudes. It has no supplementary attributes but specific conversion functions.
extends ZeroPoint [Phot:ZeroPoint]

2.1.11 objectType: SpectralLocation

vodml-id SpectralLocation
description This class is used to characterize the spectral properties of a filter.
attributes
name feature value
ucd type UCD [Phot:UCD]
vodml-id SpectralLocation.ucd
multiplicity 1
description Unified Content Description (UCD) string that specifies the nature of the spectral location for this filter.
unitexpression type ivoa:Unit
vodml-id SpectralLocation.unitexpression
multiplicity 1
description Unit string that specifies the spectral units for this filter.
value type ivoa:real
vodml-id SpectralLocation.value
multiplicity 1
description A spectral coordinate value that can be considered by the data provider as the most representative for this specific filter bandpass. as an example effective wavelength in optical.
constraints
One association at the time

2.1.12 objectType: TransmissionCurve

vodml-id TransmissionCurve
description A collection of points along the spectral axis to indicate how flux are transmitted by a filter. the transmission profile can be described by an external file and accessed through the Access instance, or can be stored as a collection of transmission points stored in the instance.
compositions
name feature value
access type Access [Phot:Access]
vodml-id TransmissionCurve.access
multiplicity 0..1
isOrdered false
description Access to an external file containing the set of Transmission Points.
transmissionPoint type TransmissionPoint [Phot:TransmissionPoint]
vodml-id TransmissionCurve.transmissionPoint
multiplicity 1..*
isOrdered false
description Set of points of the transmission curve.

2.1.13 objectType: TransmissionPoint

vodml-id TransmissionPoint
description This class is used to represent a point in the transmission function of a Filter.
attributes
name feature value
ucd type UCD [Phot:UCD]
vodml-id TransmissionPoint.ucd
multiplicity 1
description Unified Content Description (UCD) string that specifies the nature of the spectral axis in the transmission curve.
unit type ivoa:Unit
vodml-id TransmissionPoint.unit
multiplicity 1
description Unit string that specifies the spectral units for this filter.
transmissionValue type ivoa:real
vodml-id TransmissionPoint.transmissionValue
multiplicity 1
description Transmitted value for the filter at this point of the transmission curve. Usually between 0 and 1.
spectralValue type ivoa:real
vodml-id TransmissionPoint.spectralValue
multiplicity 1
description Spectral coordinate value for the transmission point.
spectralErrorValue type ivoa:real
vodml-id TransmissionPoint.spectralErrorValue
multiplicity 0..1
description Error on the spectral coordinate value for the transmission point.
constraints
One association at the time

2.1.14 enumeration: TypeOfMagSystem

vodml-id TypeOfMagSystem
description The type of System used to compute magnitude for this photometric calibration procedure .
literals
name feature value
VEGAmag vodml-id TypeOfMagSystem.VEGAmag
description Magnitude system related to VEGA.
ABmag vodml-id TypeOfMagSystem.ABmag
description AB magnitude system.
STmag vodml-id TypeOfMagSystem.STmag
description ST magnitude system.

2.1.15 primitiveType: UCD

vodml-id UCD
description Controlled vocabulary to tag measurements in table columns . See UCD IVOA Recommendation .

2.1.16 objectType: ZeroPoint

vodml-id ZeroPoint
description This class is used to characterize a zero point flux obtained during the calibration of a certain photometry filter on a certain photometric system configuration.
Subclasses in this model AsinhZeropoint LinearFluxZeropoint PogsonZeropoint
attributes
name feature value
type type ivoa:integer
vodml-id ZeroPoint.type
multiplicity 1
description Type describing the way the zeropoint value is defined . Is an integer value : {0=Pogson, 1=Asinh, 2=Linear} corresponding to zero point definitions.
referenceMagnitudeValue type ivoa:real
vodml-id ZeroPoint.referenceMagnitudeValue
multiplicity 1
description Reference magnitude value of the calibrating object as a double number to get the maximum precision. Default value is zero, but sometimes the reference mag measured is slightly above.
referenceMagnitudeError type ivoa:real
vodml-id ZeroPoint.referenceMagnitudeError
multiplicity 1
description Total error estimated on the reference magnitude value whenever applicable.
compositions
name feature value
flux type Flux [Phot:Flux]
vodml-id ZeroPoint.flux
multiplicity 0..1
isOrdered false
description TODO : Missing description : please, update your UML model asap.
constraints
One association at the time

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 Data model describing data sets Photometric properties and used for data calibration, comparison or reprocessing.
Access objectType Gathers all properties to access a resource : uri, format and size .
Access.format attribute Format of the accessed resource. typically : application/fits, application/x-votable+xml, text/csv, text/xml.
Access.reference attribute URI to access the resource.
Access.size attribute Approximate estimated size of the dataset, specified in kilobytes.
AsinhZeropoint objectType Extension of ZeroPoint to describe asinh magnitudes, a.k.a. luptitudes.
AsinhZeropoint.softeningParameter attribute Parameter used to correct the calculation of magnitudes for faint sources. Usually called 'b'. See (Lupton and Gunn et al. [1999]) for a formal explanation.
Bandwidth objectType This class is used to characterize the spectral properties of a filter.
Bandwidth.extent attribute Bandwidth’s extent of the filter , as length of the covered spectral interval , or effective width following appropriate filter type.
Bandwidth.start attribute In practice, this could be taken as the minimum value of the filter transmission curve.
Bandwidth.stop attribute In practice, this could be taken as the maximum value of the filter transmission curve.
Bandwidth.ucd attribute Unified Content Description (UCD) string that specifies the nature of the bandwidth object.
Bandwidth.unitexpression attribute Unit string that specifies the spectral units for this filter.
Flux objectType This class is used to characterize the spectral properties of a filter.
Flux.error attribute Flux value error corresponding to the reference magnitude value of the calibrating object.
Flux.ucd attribute Unified Content Description (UCD) string that specifies the nature of the spectral location for this filter.
Flux.unitexpression attribute Unit string that specifies the spectral units for this filter.
Flux.value attribute A spectral coordinate value that can be considered by the data provider as the most representative for this specific filter bandpass. as an example effective wavelength in optical.
LinearFluxZeropoint objectType Extension of ZeroPoint to describe simple linear flux photometry, commonly used in Radio, Far Infrared and X-ray spectral ranges. Although not being magnitudes as such, relative linear flux measurements can be included as a special and trivial case of magnitude.
MagnitudeSystem objectType A class to describe the Magnitude system, the reference spectrum attached and the type .
MagnitudeSystem.referenceSpectrum attribute Link to the reference spectrum as a URI.
MagnitudeSystem.type attribute Type of magnitude system used to compute the the associated zeropoint . Typical values are : VEGAmag, ABmag, STmag .
PhotCal objectType A class to bind together all photometic calibration reference information: a photometry filter, a certain magnitude system configuration and a certain zero point object.
PhotCal.identifier attribute A unique identifier of the Photometry calibration intance within the project and a filterprofile service . Suggested syntax would be: Facility/Subcategory/Band/Photometric System Type[/Suffix]
PhotCal.magnitudeSystem composition Each ZeroPoint values are given with one computation method corresponding to a defined Magnitude system.
PhotCal.photometryFilter reference Each Photcal element is related to one single Filter .
PhotCal.zeroPoint composition The ZeroPoint values for the flux to mag translation belongs to a Photcal element and is defined for one Filter element and one MagnitudeSystem .
PhotometricSystem objectType The reference photometric system used to interpret photometic measurements.
PhotometricSystem.description attribute This string contains a human readable short-text representation of the photometric system. This will allow client applications to display textual information to final users.
PhotometricSystem.detectorType attribute Detector type associated to this photometric system. Possible values are: 0 for Energy counter ( amplifiers ), 1 for Photon counter ( CCDs, Photomultipliers).
PhotometricSystem.photometryFilter composition The Photometric information is related to a Photometric system, and gathers filter descriptions, for one or several .
PhotometryFilter objectType The reference photometric system used to interpret photometic measurements.
PhotometryFilter.bandname attribute A standard label representing of the spectral band associated to this filter (if any).
PhotometryFilter.bandwidth composition Relation to the spectral coverage of the Filter.
PhotometryFilter.dateValidityFrom attribute Start time of the time coverage when this filter configuration is applicable. String time format accepted is ISO8601.
PhotometryFilter.dateValidityTo attribute End time of the time coverage when this filter configuration is applicable. String time format accepted is ISO8601.
PhotometryFilter.description attribute This string contains a verbose human readable label for the filter. This will allow client applications to display textual information to final users.
PhotometryFilter.fpsidentifier attribute IVOA identifier of the filter profile service where this photometry filter is registered to be used in the discovery of all the relevant photometry filter properties.
PhotometryFilter.identifier attribute This field identifies, in a unique way, within a certain Photometry Filter Profile service, a filter. example : Facility/Subcategory/Band[/Suffix] like SDSS/SDSS.G/G
PhotometryFilter.name attribute A human readable string to represent the filter name.
PhotometryFilter.spectralLocation composition TODO : Missing description : please, update your UML model asap.
PhotometryFilter.transmissionCurve composition Link to the Transmission Curve of the Filter, when this is described.
PogsonZeropoint objectType Extension of ZeroPoint to accommodate standard logarithm magnitudes. It has no supplementary attributes but specific conversion functions.
SpectralLocation objectType This class is used to characterize the spectral properties of a filter.
SpectralLocation.ucd attribute Unified Content Description (UCD) string that specifies the nature of the spectral location for this filter.
SpectralLocation.unitexpression attribute Unit string that specifies the spectral units for this filter.
SpectralLocation.value attribute A spectral coordinate value that can be considered by the data provider as the most representative for this specific filter bandpass. as an example effective wavelength in optical.
TransmissionCurve objectType A collection of points along the spectral axis to indicate how flux are transmitted by a filter. the transmission profile can be described by an external file and accessed through the Access instance, or can be stored as a collection of transmission points stored in the instance.
TransmissionCurve.access composition Access to an external file containing the set of Transmission Points.
TransmissionCurve.transmissionPoint composition Set of points of the transmission curve.
TransmissionPoint objectType This class is used to represent a point in the transmission function of a Filter.
TransmissionPoint.spectralErrorValue attribute Error on the spectral coordinate value for the transmission point.
TransmissionPoint.spectralValue attribute Spectral coordinate value for the transmission point.
TransmissionPoint.transmissionValue attribute Transmitted value for the filter at this point of the transmission curve. Usually between 0 and 1.
TransmissionPoint.ucd attribute Unified Content Description (UCD) string that specifies the nature of the spectral axis in the transmission curve.
TransmissionPoint.unit attribute Unit string that specifies the spectral units for this filter.
TypeOfMagSystem enumeration The type of System used to compute magnitude for this photometric calibration procedure .
TypeOfMagSystem.ABmag literal AB magnitude system.
TypeOfMagSystem.STmag literal ST magnitude system.
TypeOfMagSystem.VEGAmag literal Magnitude system related to VEGA.
UCD primitiveType Controlled vocabulary to tag measurements in table columns . See UCD IVOA Recommendation .
ZeroPoint objectType This class is used to characterize a zero point flux obtained during the calibration of a certain photometry filter on a certain photometric system configuration.
ZeroPoint.flux composition TODO : Missing description : please, update your UML model asap.
ZeroPoint.referenceMagnitudeError attribute Total error estimated on the reference magnitude value whenever applicable.
ZeroPoint.referenceMagnitudeValue attribute Reference magnitude value of the calibrating object as a double number to get the maximum precision. Default value is zero, but sometimes the reference mag measured is slightly above.
ZeroPoint.type attribute Type describing the way the zeropoint value is defined . Is an integer value : {0=Pogson, 1=Asinh, 2=Linear} corresponding to zero point definitions.

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://www.ivoa.net/xml/VODML/IVOA-v1.vo-dml.xml
documentation url https://volute.g-vo.org/svn/trunk/projects/dm/vo-dml/models/ivoa/vo-dml/IVOA-v1.0.html