Enable user defined sample and container geometry for abs correction

Framework/PythonInterface/mantid/utils/absorptioncorrutils.py

@@ -8,6 +8,7 @@
 from mantid.kernel import Logger, Property, PropertyManager
 from mantid.simpleapi import (
     AbsorptionCorrection,
+    DefineGaugeVolume,
     DeleteWorkspace,
     Divide,
     Load,
@@ -284,6 +285,10 @@ def calculate_absorption_correction(
     sample_formula,
     mass_density,
     sample_geometry={},
+    can_geometry={},
+    can_material={},
+    gauge_vol="",
+    beam_height=Property.EMPTY_DBL,
     number_density=Property.EMPTY_DBL,
     container_shape="PAC06",
     num_wl_bins=1000,
@@ -323,6 +328,10 @@ def calculate_absorption_correction(
     :param sample_formula: Sample formula to specify the Material for absorption correction
     :param mass_density: Mass density of the sample to specify the Material for absorption correction
     :param sample_geometry: Dictionary to specify the sample geometry for absorption correction
+    :param can_geometry: Dictionary to specify the container geometry for absorption correction
+    :param can_material: Dictionary to specify the container material for absorption correction
+    :param gauge_vol: String in XML form to define the gauge volume, i.e., the sample portion visible to the beam
+    :param beam_height: Optional beam height to use for absorption correction
     :param number_density: Optional number density of sample to be added to the Material for absorption correction
     :param container_shape: Shape definition of container, such as PAC06.
     :param num_wl_bins: Number of bins for calculating wavelength
@@ -344,12 +353,26 @@ def calculate_absorption_correction(
         material["SampleNumberDensity"] = number_density
 
     environment = {}
-    if container_shape:
+    find_env = True
+    if container_shape or (can_geometry and can_material):
         environment["Name"] = "InAir"
-        environment["Container"] = container_shape
+        find_env = False
+        if not (can_geometry and can_material):
+            environment["Container"] = container_shape
 
     donorWS = create_absorption_input(
-        filename, props, num_wl_bins, material=material, geometry=sample_geometry, environment=environment, metaws=metaws
+        filename,
+        props,
+        num_wl_bins,
+        material=material,
+        geometry=sample_geometry,
+        can_geometry=can_geometry,
+        can_material=can_material,
+        gauge_vol=gauge_vol,
+        beam_height=beam_height,
+        environment=environment,
+        find_environment=find_env,
+        metaws=metaws,
     )
 
     # NOTE: Ideally we want to separate cache related task from calculation,
@@ -499,6 +522,10 @@ def create_absorption_input(
     num_wl_bins=1000,
     material={},
     geometry={},
+    can_geometry={},
+    can_material={},
+    gauge_vol="",
+    beam_height=Property.EMPTY_DBL,
     environment={},
     find_environment=True,
     opt_wl_min=0,
@@ -513,6 +540,10 @@ def create_absorption_input(
     :param num_wl_bins: The number of wavelength bins used for absorption correction
     :param material: Optional material to use in SetSample
     :param geometry: Optional geometry to use in SetSample
+    :param can_geometry: Optional container geometry to use in SetSample
+    :param can_material: Optional container material to use in SetSample
+    :param gauge_vol: Optional gauge volume definition, i.e., sample portion visible to the beam.
+    :param beam_height: Optional beam height to define gauge volume
     :param environment: Optional environment to use in SetSample
     :param find_environment: Optional find_environment to control whether to figure out environment automatically.
     :param opt_wl_min: Optional minimum wavelength. If specified, this is used instead of from the props
@@ -607,11 +638,31 @@ def confirmProps(props):
         geometry = {}
     if not environment:
         environment = {}
+    if can_geometry and can_material:
+        environment = {}
 
     # Make sure one is set before calling SetSample
     if material or geometry or environment:
         mantid.simpleapi.SetSampleFromLogs(
-            InputWorkspace=absName, Material=material, Geometry=geometry, Environment=environment, FindEnvironment=find_environment
+            InputWorkspace=absName,
+            Material=material,
+            Geometry=geometry,
+            ContainerGeometry=can_geometry,
+            ContainerMaterial=can_material,
+            Environment=environment,
+            FindEnvironment=find_environment,
         )
 
+    if beam_height != Property.EMPTY_DBL and not gauge_vol:
+        gauge_vol = """<cuboid id="shape">
+            <left-front-bottom-point x="0.02" y="-{0:4.2F}" z="-0.02"  />
+            <left-front-top-point  x="0.02" y="-{0:4.2F}" z="0.02"  />
+            <left-back-bottom-point  x="-0.02" y="-{0:4.2F}" z="-0.02"  />
+            <right-front-bottom-point  x="0.02" y="{0:4.2F}" z="-0.02"  />
+            </cuboid>"""
+        gauge_vol = gauge_vol.format(beam_height / 2.0)
+
+    if gauge_vol:
+        DefineGaugeVolume(absName, gauge_vol)
+
     return absName

Framework/PythonInterface/plugins/algorithms/SNSPowderReduction.py

@@ -291,6 +291,16 @@ def PyInit(self):
         )
         self.declareProperty("SampleFormula", "", doc="Chemical formula of the sample")
         self.declareProperty("SampleGeometry", {}, doc="A dictionary of geometry parameters for the sample.")
+        self.declareProperty("ContainerGeometry", {}, doc="A dictionary of geometry parameters for the container.")
+        self.declareProperty("ContainerMaterial", {}, doc="A dictionary of material parameters for the container.")
+        self.declareProperty(
+            "GaugeVolume", "", "A string in XML form for gauge volume definition indicating sample portion visible to the beam."
+        )
+        self.declareProperty(
+            "BeamHeight",
+            defaultValue=Property.EMPTY_DBL,
+            doc="Height of the neutron beam cross section in cm",
+        )
         self.declareProperty(
             "MeasuredMassDensity",
             defaultValue=0.1,
@@ -423,6 +433,10 @@ def PyExec(self):  # noqa
         self._absMethod = self.getProperty("TypeOfCorrection").value
         self._sampleFormula = self.getProperty("SampleFormula").value
         self._sampleGeometry = self.getProperty("SampleGeometry").value
+        self._containerGeometry = self.getProperty("ContainerGeometry").value
+        self._containerMaterial = self.getProperty("ContainerMaterial").value
+        self._gaugeVolume = self.getProperty("GaugeVolume").value
+        self._beamHeight = self.getProperty("BeamHeight").value
         self._massDensity = self.getProperty("MeasuredMassDensity").value
         self._numberDensity = self.getProperty("SampleNumberDensity").value
         self._containerShape = self.getProperty("ContainerShape").value
@@ -524,6 +538,10 @@ def PyExec(self):  # noqa
             self._sampleFormula,  # Material for absorption correction
             self._massDensity,  # Mass density of the sample
             self._sampleGeometry,  # Geometry parameters for the sample
+            self._containerGeometry,  # Geometry parameters for the container
+            self._containerMaterial,  # Material parameters for the container
+            self._gaugeVolume,  # Gauge volume definition
+            self._beamHeight,  # Height of the neutron beam cross section in cm
             self._numberDensity,  # Optional number density of sample to be added
             self._containerShape,  # Shape definition of container
             self._num_wl_bins,  # Number of bins: len(ws.readX(0))-1

docs/source/release/v6.13.0/Diffraction/Powder/New_features/38887.rst

@@ -0,0 +1 @@
+- Enable user defined sample and container geometry together with the definition of gauge volume to account for the beam size. Implementation made in :ref:`SNSPowderReduction <algm-SNSPowderReduction>` and ``mantid.utils.absorptioncorrutils``.