Add test to cover Watt, N-body phase space, and evaporation spectra. Fix bug

with N-body phase space.

src/ace.F90

@@ -1033,7 +1033,7 @@ contains
 
           ! Read energy law data
           call get_energy_dist(secondary%distribution(n)%obj, LAW, &
-               JXS(11), IDAT, nuc%awr, nuc%reactions(i)%Q_value)
+               JXS(11), IDAT, nuc%awr, nuc%reactions(i + 1)%Q_value)
 
           ! <<<<<<<<<<<<<<<<<<<<<<<<<<<< REMOVE THIS <<<<<<<<<<<<<<<<<<<<<<<<<<<
           ! Before the secondary distribution refactor, when the angle/energy

tests/test_energy_laws/geometry.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<geometry>
+
+  <surface id="1" type="sphere" coeffs="0 0 0 100" boundary="vacuum"/>
+  <cell id="1" material="1" region="-1" />
+
+</geometry>

tests/test_energy_laws/materials.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0"?>
+<materials>
+
+  <material id="1">
+    <density value="20" units="g/cc" />
+    <nuclide name="U-233" xs="71c" ao="1.0" />
+    <nuclide name="H-2" xs="71c" ao="1.0" />
+    <nuclide name="Na-23" xs="71c" ao="1.0" />
+  </material>
+
+</materials>

tests/test_energy_laws/results_true.dat

@@ -0,0 +1,2 @@
+k-combined:
+2.421637E+00 5.324089E-03

tests/test_energy_laws/settings.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0"?>
+<settings>
+
+  <eigenvalue>
+    <batches>10</batches>
+    <inactive>5</inactive>
+    <particles>1000</particles>
+  </eigenvalue>
+
+  <source>
+    <space type="point" parameters="0. 0. 0." />
+  </source>
+
+</settings>

tests/test_energy_laws/test_energy_laws.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+
+"""The purpose of this test is to provide coverage of Watt, N-body phase space,
+and evaporation energy distributions. The only nuclide that uses a Watt fission
+spectrum in ENDF/B-VII.1 is U-233. The only nuclide that has a reaction using
+the N-body phase space distribution is H-2(n.2n). Several nuclides have
+reactions with evaporation spectra. In this test, the material is composed of
+U-233, H-2, and Na-23 (which has several reactions with evaporation spectra.
+
+"""
+
+import glob
+import os
+import sys
+sys.path.insert(0, os.pardir)
+from testing_harness import TestHarness
+
+
+if __name__ == '__main__':
+    harness = TestHarness('statepoint.10.*')
+    harness.main()