<?xml version="1.0" encoding="UTF-8"?>
  <!-- PDS4 XML/Schema for Name Space Id:nucspec  Version:1.1.0.0 - Mon Apr 28 22:32:24 UTC 2025 -->
  <!-- Generated from the PDS4 Information Model Version 1.24.0.0 - System Build 15.1 -->
  <!-- *** This PDS4 product schema is an operational deliverable. *** -->
  <!--                                                                           -->
  <!--               Dictionary Stack                                            -->
  <!-- 1.24.0.0 - pds: - Common Dictionary                                       -->
  <!-- 1.1.0.0 - nucspec: - nucspec                                              -->
  <!--                                                                           -->
  <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
    targetNamespace="http://pds.nasa.gov/pds4/nucspec/v1"
    xmlns:nucspec="http://pds.nasa.gov/pds4/nucspec/v1"
    xmlns:pds="http://pds.nasa.gov/pds4/pds/v1"
    elementFormDefault="qualified"
    attributeFormDefault="unqualified"
    version="1.1.0.0">
 
    <xs:import namespace="http://pds.nasa.gov/pds4/pds/v1" schemaLocation="https://pds.nasa.gov/pds4/pds/v1/PDS4_PDS_1O00.xsd"/>
 
  <xs:annotation>
    <xs:documentation>
This dictionary covers nuclear spectroscopy observations.
    </xs:documentation>
  </xs:annotation>
 
  <xs:element name="NucSpec_Observation_Properties" type="nucspec:NucSpec_Observation_Properties"> </xs:element>

  <xs:complexType name="Applicable_Records">
    <xs:annotation>
      <xs:documentation>The records to which this state
        applies.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:choice minOccurs="1" maxOccurs="1">
        <xs:element name="First_Last" type="nucspec:First_Last"> </xs:element>
        <xs:element name="First_Count" type="nucspec:First_Count"> </xs:element>
      </xs:choice>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Calibration_Reference">
    <xs:annotation>
      <xs:documentation>Contains a reference to a document that
        describes the energy calibration for the
        product.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element ref="pds:Internal_Reference" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Detector">
    <xs:annotation>
      <xs:documentation>Specifies a single detector which was active at
        the time of observation.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="name" type="nucspec:name" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="description" type="nucspec:description" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="comment" type="nucspec:comment" minOccurs="0" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Detectors">
    <xs:annotation>
      <xs:documentation>Specifies which detectors were active on an
        instrument at the time of observation.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="Detector" type="nucspec:Detector" minOccurs="1" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Energy_Calibration">
    <xs:annotation>
      <xs:documentation>Specifies methods and data used to determine the
        pulse height in energy units (e.g. MeV) for each channel of a
        pulse height spectrum.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="Polynomial" type="nucspec:Polynomial" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="Calibration_Reference" type="nucspec:Calibration_Reference" minOccurs="0" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="First_Count">
    <xs:annotation>
      <xs:documentation>Defines the records to which this state applies
        by identifying the first record (inclusive), and the number of
        contiguous records, including the first.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="first_record" type="nucspec:first_record" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="record_count" type="nucspec:record_count" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="First_Last">
    <xs:annotation>
      <xs:documentation>Defines the first and last records for which
        this state applies. The record numbers are one-based and
        inclusive.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="first_record" type="nucspec:first_record" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="last_record" type="nucspec:last_record" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Instrument_Settings">
    <xs:annotation>
      <xs:documentation>This class specifies instrument settings.
        Instrument settings are driven via a state table, which are
        associated with specific observations within the data product,
        either by directly indicating those records, or indicating the
        observation times at which certain states
        apply.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="State_Table" type="nucspec:State_Table" minOccurs="1" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="NucSpec_Observation_Properties">
    <xs:annotation>
      <xs:documentation>This class specifies properties pertaining to a
        nuclear spectroscopy observation.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="Energy_Calibration" type="nucspec:Energy_Calibration" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:element name="Instrument_Settings" type="nucspec:Instrument_Settings" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:element name="Detectors" type="nucspec:Detectors" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:element name="Observing_Conditions" type="nucspec:Observing_Conditions" minOccurs="0" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Observing_Condition">
    <xs:annotation>
      <xs:documentation>Describes the times that the activity affecting
        nuclear spectroscopy observations was in effect, along with the
        sources of the activity, if applicable.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="condition_active" nillable="true" type="nucspec:condition_active" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:element name="condition_source" nillable="true" type="nucspec:condition_source" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:element name="comment" type="nucspec:comment" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:choice minOccurs="1" maxOccurs="1">
        <xs:element name="Time_Range_UTC" type="nucspec:Time_Range_UTC"> </xs:element>
        <xs:element name="Time_Range_ET" type="nucspec:Time_Range_ET"> </xs:element>
        <xs:element name="Time_Range_SCLK" type="nucspec:Time_Range_SCLK"> </xs:element>
      </xs:choice>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Observing_Conditions">
    <xs:annotation>
      <xs:documentation>Describes activity that may affect nuclear
        spectroscopy observations.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="condition_type" nillable="true" type="nucspec:condition_type" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="Observing_Condition" type="nucspec:Observing_Condition" minOccurs="1" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
    <!-- Begin assert statements for schematron - Enumerated Values -->
    <!-- <xs:assert test="nucspec:condition_type = ('Data Glitch', 'Electron Burst', 'Gamma-ray Burst', 'SEP', 'Solar Flare')"/> -->
    <!-- End assert statements for schematron - Enumerated Values -->
  </xs:complexType>

  <xs:complexType name="Polynomial">
    <xs:annotation>
      <xs:documentation>The pulse height in energy units (e.g. MeV) is
        determined for a given channel number using the polynomial: H(x)
        = a0 + a1 x + a2 x^2 + ..., where H is pulse height with energy
        units and x is channel number.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="Polynomial_Term" type="nucspec:Polynomial_Term" minOccurs="1" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Polynomial_Term">
    <xs:annotation>
      <xs:documentation>Describes a single term in the polynomial
        function.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="order" type="nucspec:order" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="coefficient" type="nucspec:coefficient" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="State_Table">
    <xs:annotation>
      <xs:documentation>Specifies an additional look-up table that
        provides additional information about specific observations
        within the product.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element ref="pds:Internal_Reference" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element ref="pds:Local_Internal_Reference" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="State_Table_Entry" type="nucspec:State_Table_Entry" minOccurs="1" maxOccurs="unbounded"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="State_Table_Entry">
    <xs:annotation>
      <xs:documentation>Associates individual observations in the data
        product with a record in the state table, providing additional
        information on those observations.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="state_index" nillable="true" type="nucspec:state_index" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="comment" type="nucspec:comment" minOccurs="0" maxOccurs="1"> </xs:element>
      <xs:choice minOccurs="1" maxOccurs="1">
        <xs:element name="Applicable_Records" type="nucspec:Applicable_Records"> </xs:element>
        <xs:element name="State_Time" type="nucspec:State_Time"> </xs:element>
      </xs:choice>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="State_Time">
    <xs:annotation>
      <xs:documentation>The time during which this state was applicable.
        The state table entry is applicable to records in the referenced
        data table if the time of the data record, as given by
        state_time_field_name, is between the start time and stop time
        given in State_Time.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="state_time_field_name" type="nucspec:state_time_field_name" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:choice minOccurs="1" maxOccurs="1">
        <xs:element name="Time_Range_ET" type="nucspec:Time_Range_ET"> </xs:element>
        <xs:element name="Time_Range_SCLK" type="nucspec:Time_Range_SCLK"> </xs:element>
        <xs:element name="Time_Range_UTC" type="nucspec:Time_Range_UTC"> </xs:element>
      </xs:choice>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Time_Range_ET">
    <xs:annotation>
      <xs:documentation>Ephemeris time, as defined by the referenced
        field, for the first and last science data records for a
        temporally contiguous block of records with the same state or
        affected by the same conditions. These records need not be
        contiguous within the file, but there must be no records with a
        different state between the start and stop
        time.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="et_start" type="nucspec:et_start" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="et_stop" type="nucspec:et_stop" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Time_Range_SCLK">
    <xs:annotation>
      <xs:documentation>Spacecraft clock time in ticks since spacecraft
        clock start for the first and last science data records for a
        temporally contiguous block of records with the same state or
        affected by the same conditions. These records need not be
        contiguous within the file, but there must be no records with a
        different state between the start and stop
        time.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="sclk_start_time" type="nucspec:sclk_start_time" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="sclk_stop_time" type="nucspec:sclk_stop_time" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="Time_Range_UTC">
    <xs:annotation>
      <xs:documentation>Universal Coordinated Time for the first and
        last science data records for a temporally contiguous block of
        records with the same state or affected by the same conditions.
        These records need not be contiguous within the file, but there
        must be no records with a different state between the start and
        stop time.</xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="utc_start_time" type="nucspec:utc_start_time" minOccurs="1" maxOccurs="1"> </xs:element>
      <xs:element name="utc_stop_time" type="nucspec:utc_stop_time" minOccurs="1" maxOccurs="1"> </xs:element>
    </xs:sequence>
  </xs:complexType>

    <xs:annotation>
      <xs:documentation>This section contains the simpleTypes that provide more constraints
        than those at the base data type level. The simpleTypes defined here build on the base data
        types. This is another component of the common dictionary and therefore falls within the
        common namespace.
      </xs:documentation>
    </xs:annotation>

  <xs:simpleType name="coefficient">
    <xs:annotation>
      <xs:documentation>The coefficient of a single term of the
        polynomial relating channel number to pulse
        height.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Real">
     <xs:minInclusive value="-1.7976931348623157e308"/>
     <xs:maxInclusive value="1.7976931348623157e308"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="comment">
    <xs:annotation>
      <xs:documentation>Any notes about the state at the time of
        observation.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:UTF8_Text_Preserved">
     <xs:minLength value="1"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="condition_active">
    <xs:annotation>
      <xs:documentation>A flag indicating whether the condition was in
        effect at the given time.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="pds:ASCII_Boolean">
        <xs:attribute name="nilReason" type="pds:nil_reason" use="optional" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:complexType name="condition_source">
    <xs:annotation>
      <xs:documentation>A string identifying the source of the condition
        at the given time.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="pds:ASCII_Short_String_Collapsed">
        <xs:attribute name="nilReason" type="pds:nil_reason" use="optional" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:complexType name="condition_type">
    <xs:annotation>
      <xs:documentation>Remarks about the containing
        object.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="pds:ASCII_Short_String_Collapsed">
        <xs:attribute name="nilReason" type="pds:nil_reason" use="optional" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:simpleType name="description">
    <xs:annotation>
      <xs:documentation>A description for the
        detector.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:UTF8_Text_Preserved">
     <xs:minLength value="1"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="et_start_WO_Units">
    <xs:restriction base="pds:ASCII_Real">
     <xs:minInclusive value="-1.7976931348623157e308"/>
     <xs:maxInclusive value="1.7976931348623157e308"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="et_start">
    <xs:annotation>
      <xs:documentation>The earliest ephemeris time, as defined by the
        referenced field, for which this state or condition is
        applicable.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="nucspec:et_start_WO_Units">
        <xs:attribute name="unit" type="pds:Units_of_Time" use="required" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:simpleType name="et_stop_WO_Units">
    <xs:restriction base="pds:ASCII_Real">
     <xs:minInclusive value="-1.7976931348623157e308"/>
     <xs:maxInclusive value="1.7976931348623157e308"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="et_stop">
    <xs:annotation>
      <xs:documentation>The latest ephemeris time, as defined by the
        referenced field, for which this state or condition is
        applicable.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="nucspec:et_stop_WO_Units">
        <xs:attribute name="unit" type="pds:Units_of_Time" use="required" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:simpleType name="first_record">
    <xs:annotation>
      <xs:documentation>The first record for which the state applies,
        inclusive.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="1"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="last_record">
    <xs:annotation>
      <xs:documentation>The last record for which this state applies,
        inclusive.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="1"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="name">
    <xs:annotation>
<xs:documentation>The name of the detector.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:UTF8_Short_String_Collapsed">
     <xs:minLength value="1"/>
     <xs:maxLength value="255"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="order">
    <xs:annotation>
      <xs:documentation>The order of a single term of the polynomial
        relating channel number to pulse height.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="-9223372036854775808"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="record_count">
    <xs:annotation>
      <xs:documentation>The number of consecutive records, including the
        first, for which this state applies.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="1"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="sclk_start_time">
    <xs:annotation>
      <xs:documentation>The earliest spacecraft clock time, in ticks
        since spacecraft clock start, for which this state or condition
        is applicable.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="0"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="sclk_stop_time">
    <xs:annotation>
      <xs:documentation>The latest spacecraft clock time, in ticks since
        spacecraft clock start, for which this state or condition is
        applicable.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Integer">
     <xs:minInclusive value="0"/>
     <xs:maxInclusive value="9223372036854775807"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="state_index">
    <xs:annotation>
      <xs:documentation>The state_index points to a row of a look up
        table containing the instrument settings.</xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="pds:ASCII_Integer">
        <xs:attribute name="nilReason" type="pds:nil_reason" use="optional" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:simpleType name="state_time_field_name">
    <xs:annotation>
      <xs:documentation>The name of the field in the referenced data
        table that contains the time.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:UTF8_String">
     <xs:minLength value="1"/>
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="utc_start_time">
    <xs:annotation>
      <xs:documentation>The earliest Universal Coordinated Time for
        which this state or condition is applicable.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Date_Time_YMD_UTC">
  <!-- format="YYYY-MM-DDTHH:MM:SS.SSSSSSZ" -->
	   </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="utc_stop_time">
    <xs:annotation>
      <xs:documentation>The latest Universal Coordinated Time for which
        this state or condition is applicable.</xs:documentation>
    </xs:annotation>
    <xs:restriction base="pds:ASCII_Date_Time_YMD_UTC">
  <!-- format="YYYY-MM-DDTHH:MM:SS.SSSSSSZ" -->
	   </xs:restriction>
  </xs:simpleType>
</xs:schema>
