From dc3ab07cedf867dc2c870d2ddb547221c83d713f Mon Sep 17 00:00:00 2001
From: Paul Romano <paul.k.romano@gmail.com>
Date: Fri, 13 Sep 2019 10:59:18 -0500
Subject: [PATCH] Make sure no heating adjustments are made if HEATR is not run

---
 openmc/data/neutron.py | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/openmc/data/neutron.py b/openmc/data/neutron.py
index c63142d141..022cf8283d 100644
--- a/openmc/data/neutron.py
+++ b/openmc/data/neutron.py
@@ -813,6 +813,15 @@ class IncidentNeutron(EqualityMixin):
             for table in lib.tables[1:]:
                 data.add_temperature_from_ace(table)
 
+            # Add 0K elastic scattering cross section
+            if '0K' not in data.energy:
+                pendf = Evaluation(kwargs['pendf'])
+                file_obj = StringIO(pendf.section[3, 2])
+                get_head_record(file_obj)
+                params, xs = get_tab1_record(file_obj)
+                data.energy['0K'] = xs.x
+                data[2].xs['0K'] = xs
+
             # Add fission energy release data
             ev = evaluation if evaluation is not None else Evaluation(filename)
             if (1, 458) in ev.section:
@@ -833,8 +842,9 @@ class IncidentNeutron(EqualityMixin):
             # The best way to handle this is to subtract off the fission
             # KERMA that NJOY calculates and add back exactly what we want.
 
-            heating_local = Reaction(901)
-            heating_local.redundant = True
+            # If NJOY is not run with HEATR at all, skip everything below
+            if not kwargs["heatr"]:
+                return data
 
             # Helper function to get a cross section from an ENDF file on a
             # given energy grid
@@ -844,6 +854,9 @@ class IncidentNeutron(EqualityMixin):
                 _, xs = get_tab1_record(file_obj)
                 return xs(E)
 
+            heating_local = Reaction(901)
+            heating_local.redundant = True
+
             heatr_evals = get_evaluations(kwargs["heatr"])
             heatr_local_evals = get_evaluations(kwargs["heatr"] + "_local")
             for ev, ev_local in zip(heatr_evals, heatr_local_evals):
@@ -877,15 +890,6 @@ class IncidentNeutron(EqualityMixin):
 
             data.reactions[901] = heating_local
 
-            # Add 0K elastic scattering cross section
-            if '0K' not in data.energy:
-                pendf = Evaluation(kwargs['pendf'])
-                file_obj = StringIO(pendf.section[3, 2])
-                get_head_record(file_obj)
-                params, xs = get_tab1_record(file_obj)
-                data.energy['0K'] = xs.x
-                data[2].xs['0K'] = xs
-
         return data
 
     def _get_redundant_reaction(self, mt, mts):