Add multiple scattering correction to OSIRIS script

Testing/SystemTests/tests/framework/ISIS_PowderOsirisTest.py

@@ -54,6 +54,9 @@ def run_diffraction_focusing(
     sample_details=None,
     paalman_pings_events_per_point=None,
     simple_events_per_point=None,
+    neutron_paths_multiple=None,
+    neutron_paths_single=None,
+    multiple_scattering=False,
 ):
     sample_runs = sample_runs  # Choose full drange set in the cycle 1_1
 
@@ -78,6 +81,9 @@ def run_diffraction_focusing(
         empty_can_subtraction_method=empty_can_subtraction_method,
         paalman_pings_events_per_point=paalman_pings_events_per_point,
         simple_events_per_point=simple_events_per_point,
+        neutron_paths_multiple=neutron_paths_multiple,
+        neutron_paths_single=neutron_paths_single,
+        multiple_scattering=multiple_scattering,
     )
 
     focussed_rel_path = os.path.join("1_1", user_name, output_file)
@@ -103,6 +109,14 @@ def setup_inst_object(user_name, with_container=False):
     return inst_obj
 
 
+def setup_sample_details():
+    sample_details = SampleDetails(radius=1.1, height=8, center=[0, 0, 0], shape="cylinder")
+    sample_details.set_material(chemical_formula="Cr2-Ga-N", number_density=0.02)
+    sample_details.set_container(chemical_formula="Al", mass_density=2.71, radius=1.2)
+
+    return sample_details
+
+
 def _try_delete(path):
     try:
         # Use this instead of os.remove as we could be passed a non-empty dir
@@ -194,18 +208,14 @@ def skipTests(self):
 class OSIRISDiffractionFocusingWithSimpleAbsorptionCorrection(_OSIRISDiffractionFocusingTest):
     refrence_ws_name = "OSI120032_d_spacing_simple_corrected.nxs"
     required_run_files = [
-        "OSI82717.nxs",
-        "OSI82718.nxs",  # empty can
+        "OSI82717.nxs",  # empty can
         "OSIRIS00119963.nxs",
-        "OSIRIS00119964.nxs",  # van
-        "OSIRIS00120032.nxs",
+        "OSIRIS00120032.nxs",  # van
     ]
 
     def runTest(self):
         super().runPreTest()
-        sample_details = SampleDetails(radius=1.1, height=8, center=[0, 0, 0], shape="cylinder")
-        sample_details.set_material(chemical_formula="Cr2-Ga-N", number_density=10.0)
-        sample_details.set_container(chemical_formula="Al", number_density=2.7, radius=1.2)
+        sample_details = setup_sample_details()
 
         self.results = run_diffraction_focusing(
             "120032",
@@ -224,9 +234,7 @@ def skipTests(self):
 class OSIRISDiffractionFocusingWithPaalmanPingsAbsorptionCorrection(_OSIRISDiffractionFocusingTest):
     refrence_ws_name = "OSI120032_d_spacing_paalman_corrected.nxs"
     required_run_files = [
-        "OSI82717.nxs",
         "OSI82718.nxs",  # empty can
-        "OSIRIS00119963.nxs",
         "OSIRIS00119964.nxs",  # van
         "OSIRIS00120032.nxs",
     ]
@@ -235,9 +243,7 @@ def runTest(self):
         self.tolerance = 1e-8
         self.tolerance_is_rel_err = True
         super().runPreTest()
-        sample_details = SampleDetails(radius=1.1, height=8, center=[0, 0, 0], shape="cylinder")
-        sample_details.set_material(chemical_formula="Cr2-Ga-N", number_density=10.0)
-        sample_details.set_container(chemical_formula="Al", number_density=2.7, radius=1.2)
+        sample_details = setup_sample_details()
 
         self.results = run_diffraction_focusing(
             "120032",
@@ -251,3 +257,36 @@ def runTest(self):
 
     def skipTests(self):
         return False
+
+
+class OSIRISDiffractionFocusingWithMultipleScattering(_OSIRISDiffractionFocusingTest):
+    refrence_ws_name = "OSI120032_d_multiple_scattering_corrected.nxs"
+    required_run_files = [
+        "OSI82717.nxs",
+        "OSI82718.nxs",  # empty can
+        "OSIRIS00119963.nxs",
+        "OSIRIS00119964.nxs",  # van
+        "OSIRIS00120032.nxs",
+    ]
+
+    def runTest(self):
+        super().runPreTest()
+        sample_details = setup_sample_details()
+
+        self.results = run_diffraction_focusing(
+            "120032",
+            "Test_Multiple_Scattering",
+            "OSI120032_d_spacing.nxs",
+            absorb_corrections=True,
+            empty_can_subtraction_method="Simple",
+            sample_details=sample_details,
+            multiple_scattering=True,
+            simple_events_per_point=100,
+            neutron_paths_single=5,
+            neutron_paths_multiple=5,
+        )
+
+        mantid.SaveNexus(InputWorkspace=self.results, Filename=r"C:\Users\joy22959\Documents\test\multiscatt")
+
+    def skipTests(self):
+        return False

Testing/SystemTests/tests/framework/reference/OSI120032_d_multiple_scattering_corrected.nxs.md5

@@ -0,0 +1 @@
+534b1473c5f9827fec49e90563e7905c

Testing/SystemTests/tests/framework/reference/OSI120032_d_spacing_paalman_corrected.nxs.md5

@@ -1 +1 @@
-73a30dc9bf46d636b47974003819f4cc
+e4f663f1311e30a217701e9f03acb5d3

Testing/SystemTests/tests/framework/reference/OSI120032_d_spacing_simple_corrected.nxs.md5

@@ -1 +1 @@
-994ad405b8b6fe3763a0b4bc313420bc
+409654effe6096a197d437a4cc7d3f92

scripts/Diffraction/isis_powder/osiris.py

@@ -189,6 +189,9 @@ def _apply_absorb_corrections(self, run_details, ws_to_correct):
         else:
             events_per_point = 1000
 
+        if self._sample_details is None:
+            raise TypeError("To apply absorption correction you need to supply `sample_details` using `set_sample_details` method")
+
         container_geometry = self._sample_details.generate_container_geometry()
         container_material = self._sample_details.generate_container_material()
         if container_geometry and container_material:
@@ -221,6 +224,9 @@ def _apply_absorb_corrections(self, run_details, ws_to_correct):
 
         ws_to_correct = ws_to_correct / corrections
 
+        if self._inst_settings.multiple_scattering:
+            ws_to_correct = self._apply_discus_multiple_scattering(ws_to_correct)
+
         if previous_units != ws_units.wavelength:
             ws_to_correct = mantid.ConvertUnits(
                 InputWorkspace=ws_to_correct,
@@ -244,13 +250,47 @@ def _apply_paalmanpings_absorb_and_subtract_empty(self, workspace, summed_empty,
         :return: The corrected workspace.
         """
         mantid.SetInstrumentParameter(Workspace=workspace, ParameterName="deltaE-mode", Value="Elastic")
-        return absorb_corrections.apply_paalmanpings_absorb_and_subtract_empty(
+        paalman_corrected = absorb_corrections.apply_paalmanpings_absorb_and_subtract_empty(
             workspace=workspace,
             summed_empty=summed_empty,
             sample_details=sample_details,
             paalman_pings_events_per_point=paalman_pings_events_per_point,
         )
 
+        if self._inst_settings.multiple_scattering:
+            return self._apply_discus_multiple_scattering(paalman_corrected)
+
+        return paalman_corrected
+
+    def _apply_discus_multiple_scattering(self, ws_to_correct):
+        if self._inst_settings.neutron_paths_single:
+            neutron_paths_single = int(self._inst_settings.neutron_paths_single)
+        else:
+            neutron_paths_single = 100
+
+        if self._inst_settings.neutron_paths_multiple:
+            neutron_paths_multiple = int(self._inst_settings.neutron_paths_multiple)
+        else:
+            neutron_paths_multiple = 100
+
+        X = [1.0]
+        Y = [1.0]
+        Sofq_isotropic = mantid.CreateWorkspace(DataX=X, DataY=Y, UnitX="MomentumTransfer")
+
+        ws_to_correct = mantid.ConvertUnits(InputWorkspace=ws_to_correct, OutputWorkspace=ws_to_correct, Target="Momentum")
+
+        mantid.DiscusMultipleScatteringCorrection(
+            InputWorkspace=ws_to_correct,
+            StructureFactorWorkspace=Sofq_isotropic,
+            NeutronPathsSingle=neutron_paths_single,
+            NeutronPathsMultiple=neutron_paths_multiple,
+            OutputWorkspace="MSResults",
+        )
+
+        ratio = mantid.mtd["MSResults_Ratio_Single_To_All"]
+
+        return ws_to_correct * ratio
+
     def apply_drange_cropping(self, run_number_string, focused_ws):
         """
         Applies dspacing range cropping to a focused workspace.

scripts/Diffraction/isis_powder/osiris_routines/osiris_param_mapping.py

@@ -36,5 +36,8 @@
     ),
     ParamMapEntry(ext_name="paalman_pings_events_per_point", int_name="paalman_pings_events_per_point", optional=True),
     ParamMapEntry(ext_name="simple_events_per_point", int_name="simple_events_per_point", optional=True),
+    ParamMapEntry(ext_name="multiple_scattering", int_name="multiple_scattering", optional=True),
+    ParamMapEntry(ext_name="neutron_paths_single", int_name="neutron_paths_single", optional=True),
+    ParamMapEntry(ext_name="neutron_paths_multiple", int_name="neutron_paths_multiple", optional=True),
 ]
 attr_mapping.extend(PARAM_MAPPING)