From 3020800ba43c82d97825f026df72b42798996d46 Mon Sep 17 00:00:00 2001
From: Sam Shaner <shaner@mit.edu>
Date: Thu, 15 Sep 2016 10:43:45 -0400
Subject: [PATCH] moved conversion of decay_rate units from tally.F90 to
 openmc/data/product.py

---
 openmc/data/product.py |  4 +++-
 src/tally.F90          | 10 ++++------
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/openmc/data/product.py b/openmc/data/product.py
index 753888f6df..d8dc76e0f3 100644
--- a/openmc/data/product.py
+++ b/openmc/data/product.py
@@ -98,7 +98,9 @@ class Product(EqualityMixin):
     def decay_rate(self, decay_rate):
         cv.check_type('product decay rate', decay_rate, Real)
         cv.check_greater_than('product decay rate', decay_rate, 0.0, True)
-        self._decay_rate = decay_rate
+
+        # Convert the decay rate from units of inverse shakes to inverse seconds
+        self._decay_rate = decay_rate * 1.e-8
 
     @distribution.setter
     def distribution(self, distribution):
diff --git a/src/tally.F90 b/src/tally.F90
index c0e8013a3d..765e8c88a2 100644
--- a/src/tally.F90
+++ b/src/tally.F90
@@ -708,7 +708,7 @@ contains
                     score = p % absorb_wgt * yield * &
                          micro_xs(p % event_nuclide) % fission &
                          / micro_xs(p % event_nuclide) % absorption &
-                         * rxn % products(1 + d) % decay_rate * 1.e8_8
+                         * rxn % products(1 + d) % decay_rate
                   end associate
 
                   ! Tally to bin
@@ -733,7 +733,7 @@ contains
                 ! and not the MAX_DELAYED_GROUPS constant for this loop.
                 do d = 1, size(rxn % products) - 2
 
-                  score = score + rxn % products(1 + d) % decay_rate * 1.e8_8 * &
+                  score = score + rxn % products(1 + d) % decay_rate * &
                        p % absorb_wgt * micro_xs(p % event_nuclide) % fission *&
                        nuclides(p % event_nuclide) % nu(E, EMISSION_DELAYED, d)&
                        / micro_xs(p % event_nuclide) % absorption
@@ -769,11 +769,9 @@ contains
               associate (rxn => nuclides(p % event_nuclide) % &
                    reactions(nuclides(p % event_nuclide) % index_fission(1)))
 
-                ! determine score based on bank site weight and keff. Note that
-                ! the units of the decay rate have been converted from inverse
-                ! shakes to inverse seconds (1 shake = 1.e-8 seconds)
+                ! determine score based on bank site weight and keff.
                 score = score + keff * fission_bank(n_bank - p % n_bank + k) &
-                     % wgt * rxn % products(1 + g) % decay_rate * 1.e8_8
+                     % wgt * rxn % products(1 + g) % decay_rate
               end associate
 
               ! if the delayed group filter is present, tally to corresponding