VOEvent-v2.1.xsd

<?xml version='1.0' encoding='ASCII'?>
<!-- Change log
Revision 2.1 2025/01/07 BaptisteCecconi
- added "Name" complex type with "ivorn", "altIdentifier" and "role" attributes, used by "contributor"(in "Who/Author")
- added "ContributorRole" simple type, with enumeration of role values
- removed restricted list of "AstroCoordSystem": previously "idValues" type, now "xs:string"
- removed "idValues" type (and references)
- added annotation in "AstroCoords/Time" (according to STC-1.30)
- added "AstroCoords/PositionName" as "xs:string"
- added annotation to "AstroCoords/Position2D" (according to STC-1.30)
- removed restricted list of attribute "coord_system_id" in "AstroCoords": previous type=idValues (removed), new type=xs:string
- added "TimeInterval" of type "TimeInterval" in "Time"
- added "TimeInterval" type with "StartTime" and "StopTime" elements
- changed minOccurs attribute in "Position2D/Error2Radius": now set to 0
- added "Error2" element in "Position2D" with type "error2" and minOccurs=0
- added "Error3" element in "Position3D" with type "error3" and minOccurs=0
- added "coord_value" type introducing "ucd" and "unit" attributes for C1, C2 and C3 elements
- added "error2" type, with "C1" and "C2" elements
- added "error3" type, with "C1", "C2" and "C3" elements
- added "TimeFrameType" (taken from to STC-1.30)
- added "SpaceFrameType" (taken from to STC-1.30)
- updated "AstroCoords" with with sequence instead of choice
-->
<xs:schema xmlns="http://www.ivoa.net/xml/VOEvent/v2.1" xmlns:xs="http://www.w3.org/2001/XMLSchema"
  targetNamespace="http://www.ivoa.net/xml/VOEvent/v2.1" elementFormDefault="unqualified">

  <xs:element name="VOEvent">
    <xs:annotation>
      <xs:documentation> VOEvent is the root element for describing observations of immediate
        astronomical events. For more information, see
        http://www.ivoa.net/twiki/bin/view/IVOA/IvoaVOEvent. The event consists of at most one of
        each of: Who, What, WhereWhen, How, Why, Citations, Description, and
        Reference.</xs:documentation>
    </xs:annotation>
    <xs:complexType>
      <!-- Can have zero or one of each of these, in any order -->
      <xs:all>
        <xs:element name="Who" type="Who" minOccurs="0" maxOccurs="1"/>
        <xs:element name="What" type="What" minOccurs="0" maxOccurs="1"/>
        <xs:element name="WhereWhen" type="WhereWhen" minOccurs="0" maxOccurs="1"/>
        <xs:element name="How" type="How" minOccurs="0" maxOccurs="1"/>
        <xs:element name="Why" type="Why" minOccurs="0" maxOccurs="1"/>
        <xs:element name="Citations" type="Citations" minOccurs="0" maxOccurs="1"/>
        <xs:element name="Description" type="xs:string" minOccurs="0" maxOccurs="1"/>
        <xs:element name="Reference" type="Reference" minOccurs="0" maxOccurs="1"/>
      </xs:all>
      <xs:attribute name="version" type="xs:token" fixed="2.1" use="required"/>
      <xs:attribute name="ivorn" type="xs:anyURI" use="required"/>
      <xs:attribute name="role" type="roleValues" default="observation"/>
    </xs:complexType>
  </xs:element>
  <xs:simpleType name="roleValues">
    <xs:restriction base="xs:string">
      <xs:enumeration value="observation"/>
      <xs:enumeration value="prediction"/>
      <xs:enumeration value="utility"/>
      <xs:enumeration value="test"/>
    </xs:restriction>
  </xs:simpleType>


  <xs:complexType name="Who">
    <xs:annotation>
      <xs:documentation> Who: Curation Metadata </xs:documentation>
    </xs:annotation>
    <xs:all>
      <!-- Can have zero or one of each of these. Schema is loose because
        should have AuthorIVORN *or* Author -->
      <xs:element name="AuthorIVORN" type="xs:anyURI" minOccurs="0"/>
      <xs:element name="Date" type="xs:dateTime" minOccurs="0"/>
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0"/>
      <xs:element name="Author" minOccurs="0">
        <xs:annotation>
          <xs:documentation> Author information follows the IVOA curation information schema: the
            organization responsible for the packet can have a title, short name or acronym, and a
            logo. A contact person has a name, email, and phone number. Other contributors can also
            be noted. </xs:documentation>
        </xs:annotation>
        <xs:complexType>
          <xs:choice maxOccurs="unbounded">
            <xs:element name="title" type="xs:string"/>
            <xs:element name="shortName" type="xs:string"/>
            <xs:element name="logoURL" type="xs:anyURI"/>
            <xs:element name="contactName" type="xs:string"/>
            <xs:element name="contactEmail" type="xs:string"/>
            <xs:element name="contactPhone" type="xs:string"/>
            <xs:element name="contributor" type="Name"/>
          </xs:choice>
        </xs:complexType>
      </xs:element>
    </xs:all>
  </xs:complexType>


  <xs:complexType name="What">
    <xs:annotation>
      <xs:documentation> What: Event Characterization. This is the part of the data model that is
        chosen by the Authoer of the event rather than the IVOA. There can be Params, that may be in
        Groups, and Tables, and simpleTimeSeries. There can also be Description and Reference as
        with most VOEvent elements. </xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <!-- can have any number of any of these in any order  -->
      <xs:element name="Param" type="Param" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Group" type="Group" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Table" type="Table" minOccurs="0" maxOccurs="unbounded"/>
      <!--<xs:element ref="sts:SimpleTimeseries"          minOccurs="0" maxOccurs="unbounded"/>-->
      <xs:element name="Description" type="xs:string" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Reference" type="Reference" minOccurs="0" maxOccurs="unbounded"/>
    </xs:choice>
  </xs:complexType>


  <xs:complexType name="Param">
    <xs:annotation>
      <xs:documentation> What/Param definition. A Param has name, value, ucd, unit, dataType; and
        may have Description and Reference.</xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Value" type="xs:string" minOccurs="0" maxOccurs="1"/>
    </xs:choice>
    <xs:attribute name="name" type="xs:string"/>
    <xs:attribute name="ucd" type="xs:string"/>
    <xs:attribute name="value" type="xs:string"/>
    <xs:attribute name="unit" type="xs:string"/>
    <xs:attribute name="dataType" type="dataType" default="string"/>
    <xs:attribute name="utype" type="xs:string"/>
  </xs:complexType>
  <xs:simpleType name="dataType">
    <xs:restriction base="xs:string">
      <xs:enumeration value="string"/>
      <xs:enumeration value="float"/>
      <xs:enumeration value="int"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="Group">
    <xs:annotation>
      <xs:documentation> What/Group definition: A group is a collection of Params, with name and
        type attributes.</xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Param" type="Param" maxOccurs="unbounded"/>
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0"/>
    </xs:choice>
    <xs:attribute name="name" type="xs:string"/>
    <xs:attribute name="type" type="xs:string"/>
  </xs:complexType>


  <xs:complexType name="Table">
    <xs:annotation>
      <xs:documentation> What/Table definition. This small Table has Fields for the column
        definitions, and Data to hold the table data, with TR for row and TD for value of a table
        cell.</xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0"/>
      <xs:element name="Param" type="Param" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Field" type="Field" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Data" type="Data" minOccurs="1" maxOccurs="1"/>
    </xs:choice>
    <xs:attribute name="name" type="xs:string"/>
    <xs:attribute name="type" type="xs:string"/>
  </xs:complexType>
  <xs:complexType name="Field">
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0"/>
    </xs:choice>
    <xs:attribute name="name" type="xs:string"/>
    <xs:attribute name="ucd" type="xs:string"/>
    <xs:attribute name="unit" type="xs:string"/>
    <xs:attribute name="dataType" type="dataType" default="string"/>
    <xs:attribute name="utype" type="xs:string"/>
  </xs:complexType>
  <xs:complexType name="Data">
    <xs:choice maxOccurs="unbounded">
      <xs:element name="TR" type="TR"/>
    </xs:choice>
  </xs:complexType>
  <xs:complexType name="TR">
    <xs:choice maxOccurs="unbounded">
      <xs:element name="TD" type="xs:string"/>
    </xs:choice>
  </xs:complexType>


  <xs:complexType name="WhereWhen">
    <xs:annotation>
      <xs:documentation> WhereWhen: Space-Time Coordinates. Lots and lots of elements here, but the
        import is that each event has these: observatory, coord_system, time, timeError, longitude,
        latitude, posError.</xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="ObsDataLocation" type="ObsDataLocation" minOccurs="1" maxOccurs="1"/>
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
      <xs:element name="Reference" type="Reference" minOccurs="0"/>
    </xs:choice>
    <xs:attribute name="id" type="xs:ID" use="optional"/>
  </xs:complexType>

  <xs:complexType name="ObsDataLocation">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="ObservatoryLocation" minOccurs="1" maxOccurs="1" type="ObservatoryLocation"/>
      <xs:element name="ObservationLocation" minOccurs="1" maxOccurs="1" type="ObservationLocation"
      />
    </xs:all>
  </xs:complexType>

  <xs:complexType name="ObservationLocation">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="AstroCoordSystem" type="AstroCoordSystem" minOccurs="1" maxOccurs="1"/>
      <xs:element name="AstroCoords" type="AstroCoords" minOccurs="1" maxOccurs="1"/>
    </xs:all>
  </xs:complexType>

  <xs:complexType name="AstroCoordSystem">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <!-- The empty sequence closes this to content -->
    <xs:sequence>
      <xs:element minOccurs="0" name="TimeFrame" type="TimeFrameType"/>
      <xs:element minOccurs="0" name="SpaceFrame" type="SpaceFrameType"/>
    </xs:sequence>
    <xs:attribute name="id" type="xs:ID"/>
  </xs:complexType>



  <xs:complexType name="AstroCoords">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="Time" type="Time" minOccurs="0">
        <xs:annotation>
          <xs:documentation>Time instant or Time Interval for the event</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element minOccurs="0" name="PositionName" type="xs:string">
        <xs:annotation>
          <xs:documentation>Named position for the event</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element name="Position2D" type="Position2D" minOccurs="0">
        <xs:annotation>
          <xs:documentation>Position for the event (2D coordSystem)</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element name="Position3D" type="Position3D" minOccurs="0">
        <xs:annotation>
          <xs:documentation>Position for the event (3D coordSystem)</xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
    <xs:attribute name="coord_system_id" type="xs:string"/>
  </xs:complexType>

  <xs:complexType name="Time">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:sequence maxOccurs="unbounded">
      <xs:element name="TimeInstant" type="TimeInstant" maxOccurs="1" minOccurs="0"/>
      <xs:element name="TimeInterval" type="TimeInterval" maxOccurs="1" minOccurs="0"/>
      <xs:element name="Error" type="xs:float" maxOccurs="1" minOccurs="0"/>
    </xs:sequence>
    <xs:attribute name="unit" type="xs:string"/>
  </xs:complexType>

  <xs:complexType name="TimeInstant">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:sequence maxOccurs="unbounded">
      <xs:element name="ISOTime" type="xs:string" minOccurs="0" maxOccurs="1"/>
      <xs:element name="TimeOffset" type="xs:float" minOccurs="0" maxOccurs="1"/>
      <xs:element name="TimeScale" type="xs:string" minOccurs="0" maxOccurs="1"/>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="TimeInterval">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:sequence maxOccurs="unbounded">
      <xs:element name="ISOTimeStart" type="xs:string" minOccurs="0" maxOccurs="1"/>
      <xs:element name="ISOTimeStop" type="xs:string" minOccurs="0" maxOccurs="1"/>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Position2D">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="Name1" type="xs:string" minOccurs="0"/>
      <xs:element name="Name2" type="xs:string" minOccurs="0"/>
      <xs:element name="Value2" type="Value2"/>
      <xs:element name="Error2Radius" type="xs:float" minOccurs="0"/>
      <xs:element name="Error2" type="error2" minOccurs="0"/>
    </xs:all>
    <xs:attribute name="unit" type="xs:string"/>
  </xs:complexType>

  <xs:complexType name="Position3D">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="Name1" type="xs:string" minOccurs="0"/>
      <xs:element name="Name2" type="xs:string" minOccurs="0"/>
      <xs:element name="Name3" type="xs:string" minOccurs="0"/>
      <xs:element name="Value3" type="Value3"/>
      <xs:element name="Error3" type="error3" minOccurs="0"/>
    </xs:all>
    <xs:attribute name="unit" type="xs:string"/>
  </xs:complexType>
  <xs:complexType name="coord_value">
    <xs:annotation>
      <xs:documentation>element for each axis </xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="xs:float">
        <xs:attribute name="ucd" type="xs:string"/>
        <xs:attribute name="pos_unit" type="xs:string"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>


  <xs:complexType name="Value2">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="C1" type="coord_value"/>
      <xs:element name="C2" type="coord_value"/>
    </xs:all>
  </xs:complexType>

  <xs:complexType name="error2">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="C1" type="coord_value" minOccurs="0"/>
      <xs:element name="C2" type="coord_value" minOccurs="0"/>
    </xs:all>
  </xs:complexType>


  <xs:complexType name="Value3">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="C1" type="coord_value"/>
      <xs:element name="C2" type="coord_value"/>
      <xs:element name="C3" type="coord_value"/>
    </xs:all>
  </xs:complexType>

  <xs:complexType name="error3">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="C1" type="coord_value" minOccurs="0"/>
      <xs:element name="C2" type="coord_value" minOccurs="0"/>
      <xs:element name="C3" type="coord_value" minOccurs="0"/>
    </xs:all>
  </xs:complexType>


  <xs:complexType name="ObservatoryLocation">
    <xs:annotation>
      <xs:documentation> Part of WhereWhen</xs:documentation>
    </xs:annotation>
    <xs:all>
      <xs:element name="AstroCoordSystem" type="AstroCoordSystem" minOccurs="0" maxOccurs="1"/>
      <xs:element name="AstroCoords" type="AstroCoords" minOccurs="0" maxOccurs="1"/>
    </xs:all>
    <xs:attribute name="id" type="xs:string"/>
  </xs:complexType>

  <xs:complexType name="How">
    <xs:annotation>
      <xs:documentation> How: Instrument Configuration. Built with some Description and Reference
        elements. </xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Description" type="xs:string"/>
      <xs:element name="Reference" type="Reference"/>
    </xs:choice>
  </xs:complexType>

  <xs:complexType name="Why">
    <xs:annotation>
      <xs:documentation> Why: Initial Scientific Assessment. Can make simple Concept/Name/Desc/Ref
        for the inference or use multiple Inference containers for more semantic sophistication.
      </xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Name" type="xs:string"/>
      <xs:element name="Concept" type="xs:string"/>
      <xs:element name="Inference" type="Inference"/>
      <xs:element name="Description" type="xs:string"/>
      <xs:element name="Reference" type="Reference"/>
    </xs:choice>
    <xs:attribute name="importance" type="xs:float"/>
    <xs:attribute name="expires" type="xs:dateTime"/>
  </xs:complexType>

  <xs:complexType name="Inference">
    <xs:annotation>
      <xs:documentation> Why/Inference: A container for a more nuanced expression, including
        relationships and probability. </xs:documentation>
    </xs:annotation>
    <xs:choice maxOccurs="unbounded">
      <xs:element name="Name" type="xs:string"/>
      <xs:element name="Concept" type="xs:string"/>
      <xs:element name="Description" type="xs:string"/>
      <xs:element name="Reference" type="Reference"/>
    </xs:choice>
    <xs:attribute name="probability" type="smallFloat"/>
    <xs:attribute name="relation" type="xs:string"/>
  </xs:complexType>
  <xs:simpleType name="smallFloat">
    <xs:restriction base="xs:float">
      <xs:minInclusive value="0.0"/>
      <xs:maxInclusive value="1.0"/>
    </xs:restriction>
  </xs:simpleType>


  <xs:complexType name="Citations">
    <xs:annotation>
      <xs:documentation> Citations: Follow-up Observations. This section is a sequence of EventIVORN
        elements, each of which has the IVORN of a cited event. </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="EventIVORN" type="EventIVORN" maxOccurs="unbounded"/>
      <xs:element name="Description" type="xs:string" minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="EventIVORN">
    <xs:annotation>
      <xs:documentation> Citations/EventIVORN. The value is the IVORN of the cited event, the 'cite'
        attribute is the nature of that relationship, choosing from 'followup', 'supersedes', or
        'retraction'.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute name="cite" type="citeValues"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:simpleType name="citeValues">
    <xs:restriction base="xs:string">
      <xs:enumeration value="followup"/>
      <xs:enumeration value="supersedes"/>
      <xs:enumeration value="retraction"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="Reference">
    <xs:annotation>
      <xs:documentation> Reference: External Content. The payload is the uri, and the 'type'
        describes the nature of the data under that uri. The Reference can also be named.
      </xs:documentation>
    </xs:annotation>
    <xs:sequence/>
    <xs:attribute name="uri" type="xs:anyURI" use="required"/>
    <xs:attribute name="type" type="xs:string"/>
    <xs:attribute name="mimetype" type="xs:string"/>
    <xs:attribute name="meaning" type="xs:anyURI"/>
  </xs:complexType>

  <xs:complexType name="TimeFrameType">
    <xs:annotation>
      <xs:documentation>The time reference frame consists of a time scale, a time format, and a
        reference time, if needed. A TimeFrame has to have at least an Id.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element minOccurs="0" name="Name" type="xs:string"/>
      <xs:element minOccurs="0" name="ReferencePosition" type="xs:string">
        <xs:annotation>
          <xs:documentation>Origin of the coordinate reference frame: either a "known place" such as
            geocenter or barycenter, or a position defined in a known coordinate
            system. Values should be taken from: http://www.ivoa.net/rdf/refposition</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element minOccurs="0" name="TimeScale" type="xs:string">
        <xs:annotation>
          <xs:documentation>Values should be taken from: http://www.ivoa.net/rdf/timescale</xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
    <xs:attribute name="id" type="xs:ID"/>
  </xs:complexType>
  <xs:complexType name="SpaceFrameType">
    <xs:annotation>
      <xs:documentation>A SpaceFrame has to have at least an Id</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element minOccurs="0" name="Name" type="xs:string"/>
      <xs:element minOccurs="0" name="SpaceRefFrame" type="xs:string">
        <xs:annotation>
          <xs:documentation>Coordinate reference frame: optional equinox with either a standard
            reference system (ICRS, FK5, FK4) and optional standard pole (equatorial, ecliptic,
            galactic, etc.), or pole (positive Z-axis) and positive X-axis direction. Values should
            be taken from: http://www.ivoa.net/rdf/refframe</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element minOccurs="0" name="CoordFlavor" type="xs:string">
        <xs:annotation>
          <xs:documentation>Provides the coordinate definitions: number of axes, SPHERICAL,
            CARTESIAN, UNITSPHERE, POLAR, or HEALPIX, presence of velocities</xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element minOccurs="0" name="ReferencePosition" type="xs:string">
        <xs:annotation>
          <xs:documentation>Origin of the coordinate reference frame: either a "known place" such as
            geocenter or barycenter, or a position defined in a known coordinate
            system. Values should be taken from: http://www.ivoa.net/rdf/refposition</xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
    <xs:attribute name="id" type="xs:ID"/>
  </xs:complexType>
  <xs:complexType name="Name">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute name="altIdentifier" type="xs:anyURI">
          <xs:annotation>
            <xs:documentation>Alternate contact identifier in URI form. The main usage is to refer
              to ORCIDs (e.g.: https://orcid.org/0000-0001-2345-6789)</xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name="role" type="contributorRole">
          <xs:annotation>
            <xs:documentation>Role of the Contributor </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name="ivorn" type="xs:anyURI">
          <xs:annotation>
            <xs:documentation>Person id in the VO registry, if available</xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:simpleType name="contributorRole">
    <xs:annotation>
      <xs:documentation>The list of contributor roles is extracted from the DataCite Schema v4.3.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="xs:string">
      <xs:enumeration value="ContactPerson"/>
      <xs:enumeration value="DataCollector"/>
      <xs:enumeration value="DataCurator"/>
      <xs:enumeration value="DataManager"/>
      <xs:enumeration value="Distributor"/>
      <xs:enumeration value="Editor"/>
      <xs:enumeration value="HostingInstitution"/>
      <xs:enumeration value="Producer"/>
      <xs:enumeration value="ProjectLeader"/>
      <xs:enumeration value="ProjectManager"/>
      <xs:enumeration value="ProjectMember"/>
      <xs:enumeration value="RegistrationAgency"/>
      <xs:enumeration value="RegistrationAuthority"/>
      <xs:enumeration value="RelatedPerson"/>
      <xs:enumeration value="Researcher"/>
      <xs:enumeration value="ResearchGroup"/>
      <xs:enumeration value="RightsHolder"/>
      <xs:enumeration value="Sponsor"/>
      <xs:enumeration value="Supervisor"/>
      <xs:enumeration value="WorkPackageLeader"/>
      <xs:enumeration value="Other"/>
    </xs:restriction>
  </xs:simpleType>
</xs:schema>