diff --git a/docs/source/pythonapi/examples/mgxs-part-i.ipynb b/docs/source/pythonapi/examples/mgxs-part-i.ipynb
index e7b8cc73a..b4e6d84fe 100644
--- a/docs/source/pythonapi/examples/mgxs-part-i.ipynb
+++ b/docs/source/pythonapi/examples/mgxs-part-i.ipynb
@@ -398,17 +398,10 @@
    },
    "outputs": [],
    "source": [
-    "# Instantiate a tally Mesh\n",
-    "mesh = openmc.Mesh(name='mesh')\n",
-    "mesh.type = 'regular'\n",
-    "mesh.dimension = [2, 2]\n",
-    "mesh.lower_left = [-0.63, -0.63]\n",
-    "mesh.upper_right = [+0.63, +0.63]\n",
-    "\n",
     "# Instantiate a few different sections\n",
-    "total = mgxs.TotalXS(domain=mesh, groups=groups)\n",
-    "absorption = mgxs.AbsorptionXS(domain=mesh, groups=groups)\n",
-    "scattering = mgxs.ScatterXS(domain=mesh, groups=groups)"
+    "total = mgxs.TotalXS(domain=cell, groups=groups)\n",
+    "absorption = mgxs.AbsorptionXS(domain=cell, groups=groups)\n",
+    "scattering = mgxs.ScatterXS(domain=cell, groups=groups)"
    ]
   },
   {
@@ -432,7 +425,7 @@
        "              \tID             =\t10000\n",
        "              \tName           =\t\n",
        "              \tFilters        =\t\n",
-       "                              \t\tmesh\t[10000]\n",
+       "                              \t\tcell\t[1]\n",
        "                              \t\tenergy\t[  0.00000000e+00   6.25000000e-07   2.00000000e+01]\n",
        "              \tNuclides       =\ttotal \n",
        "              \tScores         =\t['flux']\n",
@@ -440,7 +433,7 @@
        "              \tID             =\t10001\n",
        "              \tName           =\t\n",
        "              \tFilters        =\t\n",
-       "                              \t\tmesh\t[10000]\n",
+       "                              \t\tcell\t[1]\n",
        "                              \t\tenergy\t[  0.00000000e+00   6.25000000e-07   2.00000000e+01]\n",
        "              \tNuclides       =\ttotal \n",
        "              \tScores         =\t['absorption']\n",
@@ -522,7 +515,7 @@
       "      License:        http://openmc.readthedocs.io/en/latest/license.html\n",
       "      Version:        0.8.0\n",
       "      Git SHA1:       16e74656b028875a7ebcb90df07293c5f1cc56a4\n",
-      "      Date/Time:      2016-07-29 13:20:18\n",
+      "      Date/Time:      2016-07-29 13:40:25\n",
       "      MPI Processes:  1\n",
       "\n",
       " ===========================================================================\n",
@@ -608,20 +601,20 @@
       "\n",
       " =======================>     TIMING STATISTICS     <=======================\n",
       "\n",
-      " Total time for initialization     =  3.8300E-01 seconds\n",
-      "   Reading cross sections          =  2.0900E-01 seconds\n",
-      " Total time in simulation          =  2.3245E+01 seconds\n",
-      "   Time in transport only          =  2.3223E+01 seconds\n",
-      "   Time in inactive batches        =  2.0320E+00 seconds\n",
-      "   Time in active batches          =  2.1213E+01 seconds\n",
-      "   Time synchronizing fission bank =  1.0000E-02 seconds\n",
-      "     Sampling source sites         =  7.0000E-03 seconds\n",
-      "     SEND/RECV source sites        =  2.0000E-03 seconds\n",
-      "   Time accumulating tallies       =  0.0000E+00 seconds\n",
+      " Total time for initialization     =  3.9900E-01 seconds\n",
+      "   Reading cross sections          =  2.1800E-01 seconds\n",
+      " Total time in simulation          =  2.0870E+01 seconds\n",
+      "   Time in transport only          =  2.0855E+01 seconds\n",
+      "   Time in inactive batches        =  2.3100E+00 seconds\n",
+      "   Time in active batches          =  1.8560E+01 seconds\n",
+      "   Time synchronizing fission bank =  4.0000E-03 seconds\n",
+      "     Sampling source sites         =  3.0000E-03 seconds\n",
+      "     SEND/RECV source sites        =  1.0000E-03 seconds\n",
+      "   Time accumulating tallies       =  2.0000E-03 seconds\n",
       " Total time for finalization       =  1.0000E-03 seconds\n",
-      " Total time elapsed                =  2.3642E+01 seconds\n",
-      " Calculation Rate (inactive)       =  12303.1 neutrons/second\n",
-      " Calculation Rate (active)         =  4714.09 neutrons/second\n",
+      " Total time elapsed                =  2.1283E+01 seconds\n",
+      " Calculation Rate (inactive)       =  10822.5 neutrons/second\n",
+      " Calculation Rate (active)         =  5387.93 neutrons/second\n",
       "\n",
       " ============================>     RESULTS     <============================\n",
       "\n",
@@ -737,26 +730,11 @@
      "text": [
       "Multi-Group XS\n",
       "\tReaction Type  =\ttotal\n",
-      "\tDomain Type    =\tmesh\n",
-      "\tDomain ID      =\t10000\n",
+      "\tDomain Type    =\tcell\n",
+      "\tDomain ID      =\t1\n",
       "\tCross Sections [cm^-1]:\n",
-      "            Group 1 [6.25e-07   - 20.0      MeV]:\t6.81e-01 +/- 3.06e-01%\n",
-      "            Group 2 [0.0        - 6.25e-07  MeV]:\t1.40e+00 +/- 6.94e-01%\n",
-      "\n",
-      "\n",
-      "\tCross Sections [cm^-1]:\n",
-      "            Group 1 [6.25e-07   - 20.0      MeV]:\t6.81e-01 +/- 3.19e-01%\n",
-      "            Group 2 [0.0        - 6.25e-07  MeV]:\t1.40e+00 +/- 7.34e-01%\n",
-      "\n",
-      "\n",
-      "\tCross Sections [cm^-1]:\n",
-      "            Group 1 [6.25e-07   - 20.0      MeV]:\t6.82e-01 +/- 3.01e-01%\n",
-      "            Group 2 [0.0        - 6.25e-07  MeV]:\t1.40e+00 +/- 7.23e-01%\n",
-      "\n",
-      "\n",
-      "\tCross Sections [cm^-1]:\n",
-      "            Group 1 [6.25e-07   - 20.0      MeV]:\t6.80e-01 +/- 3.34e-01%\n",
-      "            Group 2 [0.0        - 6.25e-07  MeV]:\t1.40e+00 +/- 5.92e-01%\n",
+      "            Group 1 [6.25e-07   - 20.0      MeV]:\t6.81e-01 +/- 2.69e-01%\n",
+      "            Group 2 [0.0        - 6.25e-07  MeV]:\t1.40e+00 +/- 5.93e-01%\n",
       "\n",
       "\n",
       "\n"
@@ -787,121 +765,40 @@
        "<div>\n",
        "<table border=\"1\" class=\"dataframe\">\n",
        "  <thead>\n",
-       "    <tr>\n",
+       "    <tr style=\"text-align: right;\">\n",
        "      <th></th>\n",
-       "      <th colspan=\"3\" halign=\"left\">mesh 10000</th>\n",
+       "      <th>cell</th>\n",
        "      <th>group in</th>\n",
        "      <th>nuclide</th>\n",
        "      <th>mean</th>\n",
        "      <th>std. dev.</th>\n",
        "    </tr>\n",
-       "    <tr>\n",
-       "      <th></th>\n",
-       "      <th>x</th>\n",
-       "      <th>y</th>\n",
-       "      <th>z</th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "    </tr>\n",
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
        "      <td>1</td>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>total</td>\n",
-       "      <td>0.667691</td>\n",
-       "      <td>0.002046</td>\n",
+       "      <td>0.667787</td>\n",
+       "      <td>0.001802</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>2</td>\n",
        "      <td>total</td>\n",
-       "      <td>1.291709</td>\n",
-       "      <td>0.008941</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>total</td>\n",
-       "      <td>0.667474</td>\n",
-       "      <td>0.002119</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>total</td>\n",
-       "      <td>1.292677</td>\n",
-       "      <td>0.009479</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>total</td>\n",
-       "      <td>0.668766</td>\n",
-       "      <td>0.002021</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>4</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>total</td>\n",
-       "      <td>1.292504</td>\n",
-       "      <td>0.009323</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>7</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>total</td>\n",
-       "      <td>0.667218</td>\n",
-       "      <td>0.002220</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>6</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>total</td>\n",
-       "      <td>1.291160</td>\n",
-       "      <td>0.007613</td>\n",
+       "      <td>1.292013</td>\n",
+       "      <td>0.007642</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "  mesh 10000       group in nuclide      mean std. dev.\n",
-       "           x  y  z                                     \n",
-       "1          1  1  1        1   total  0.667691  0.002046\n",
-       "0          1  1  1        2   total  1.291709  0.008941\n",
-       "3          1  2  1        1   total  0.667474  0.002119\n",
-       "2          1  2  1        2   total  1.292677  0.009479\n",
-       "5          2  1  1        1   total  0.668766  0.002021\n",
-       "4          2  1  1        2   total  1.292504  0.009323\n",
-       "7          2  2  1        1   total  0.667218  0.002220\n",
-       "6          2  2  1        2   total  1.291160  0.007613"
+       "   cell  group in nuclide      mean  std. dev.\n",
+       "1     1         1   total  0.667787   0.001802\n",
+       "0     1         2   total  1.292013   0.007642"
       ]
      },
      "execution_count": 19,
@@ -961,9 +858,9 @@
        "<div>\n",
        "<table border=\"1\" class=\"dataframe\">\n",
        "  <thead>\n",
-       "    <tr>\n",
+       "    <tr style=\"text-align: right;\">\n",
        "      <th></th>\n",
-       "      <th colspan=\"3\" halign=\"left\">mesh 10000</th>\n",
+       "      <th>cell</th>\n",
        "      <th>energy low [MeV]</th>\n",
        "      <th>energy high [MeV]</th>\n",
        "      <th>nuclide</th>\n",
@@ -971,142 +868,40 @@
        "      <th>mean</th>\n",
        "      <th>std. dev.</th>\n",
        "    </tr>\n",
-       "    <tr>\n",
-       "      <th></th>\n",
-       "      <th>x</th>\n",
-       "      <th>y</th>\n",
-       "      <th>z</th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "    </tr>\n",
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>0.000000e+00</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>total</td>\n",
        "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>-1.332268e-15</td>\n",
-       "      <td>0.013214</td>\n",
+       "      <td>-3.996803e-15</td>\n",
+       "      <td>0.011292</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>2.000000e+01</td>\n",
        "      <td>total</td>\n",
        "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>-2.220446e-16</td>\n",
-       "      <td>0.002922</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>4.440892e-16</td>\n",
-       "      <td>0.014000</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>2.331468e-15</td>\n",
-       "      <td>0.003034</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>4</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>-6.661338e-16</td>\n",
-       "      <td>0.013782</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>-9.992007e-16</td>\n",
-       "      <td>0.002880</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>6</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>4.440892e-16</td>\n",
-       "      <td>0.011257</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>7</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((total / flux) - (absorption / flux)) - (sca...</td>\n",
-       "      <td>7.771561e-16</td>\n",
-       "      <td>0.003177</td>\n",
+       "      <td>5.551115e-16</td>\n",
+       "      <td>0.002570</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "  mesh 10000       energy low [MeV] energy high [MeV] nuclide  \\\n",
-       "           x  y  z                                              \n",
-       "0          1  1  1         0.00e+00          6.25e-07   total   \n",
-       "1          1  1  1         6.25e-07          2.00e+01   total   \n",
-       "2          1  2  1         0.00e+00          6.25e-07   total   \n",
-       "3          1  2  1         6.25e-07          2.00e+01   total   \n",
-       "4          2  1  1         0.00e+00          6.25e-07   total   \n",
-       "5          2  1  1         6.25e-07          2.00e+01   total   \n",
-       "6          2  2  1         0.00e+00          6.25e-07   total   \n",
-       "7          2  2  1         6.25e-07          2.00e+01   total   \n",
+       "   cell  energy low [MeV]  energy high [MeV] nuclide  \\\n",
+       "0     1          0.00e+00           6.25e-07   total   \n",
+       "1     1          6.25e-07           2.00e+01   total   \n",
        "\n",
-       "                                               score      mean std. dev.  \n",
-       "                                                                          \n",
-       "0  (((total / flux) - (absorption / flux)) - (sca... -1.33e-15  1.32e-02  \n",
-       "1  (((total / flux) - (absorption / flux)) - (sca... -2.22e-16  2.92e-03  \n",
-       "2  (((total / flux) - (absorption / flux)) - (sca...  4.44e-16  1.40e-02  \n",
-       "3  (((total / flux) - (absorption / flux)) - (sca...  2.33e-15  3.03e-03  \n",
-       "4  (((total / flux) - (absorption / flux)) - (sca... -6.66e-16  1.38e-02  \n",
-       "5  (((total / flux) - (absorption / flux)) - (sca... -9.99e-16  2.88e-03  \n",
-       "6  (((total / flux) - (absorption / flux)) - (sca...  4.44e-16  1.13e-02  \n",
-       "7  (((total / flux) - (absorption / flux)) - (sca...  7.77e-16  3.18e-03  "
+       "                                               score      mean  std. dev.  \n",
+       "0  (((total / flux) - (absorption / flux)) - (sca... -4.00e-15   1.13e-02  \n",
+       "1  (((total / flux) - (absorption / flux)) - (sca...  5.55e-16   2.57e-03  "
       ]
      },
      "execution_count": 21,
@@ -1142,9 +937,9 @@
        "<div>\n",
        "<table border=\"1\" class=\"dataframe\">\n",
        "  <thead>\n",
-       "    <tr>\n",
+       "    <tr style=\"text-align: right;\">\n",
        "      <th></th>\n",
-       "      <th colspan=\"3\" halign=\"left\">mesh 10000</th>\n",
+       "      <th>cell</th>\n",
        "      <th>energy low [MeV]</th>\n",
        "      <th>energy high [MeV]</th>\n",
        "      <th>nuclide</th>\n",
@@ -1152,142 +947,40 @@
        "      <th>mean</th>\n",
        "      <th>std. dev.</th>\n",
        "    </tr>\n",
-       "    <tr>\n",
-       "      <th></th>\n",
-       "      <th>x</th>\n",
-       "      <th>y</th>\n",
-       "      <th>z</th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "    </tr>\n",
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>0.000000e+00</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>total</td>\n",
        "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.076077</td>\n",
-       "      <td>0.000762</td>\n",
+       "      <td>0.076115</td>\n",
+       "      <td>0.000649</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>2.000000e+01</td>\n",
        "      <td>total</td>\n",
        "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.019242</td>\n",
-       "      <td>0.000160</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.076173</td>\n",
-       "      <td>0.000800</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.019372</td>\n",
-       "      <td>0.000136</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>4</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.076183</td>\n",
-       "      <td>0.000796</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.019364</td>\n",
-       "      <td>0.000154</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>6</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.076027</td>\n",
-       "      <td>0.000654</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>7</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((absorption / flux) / (total / flux))</td>\n",
-       "      <td>0.019074</td>\n",
-       "      <td>0.000153</td>\n",
+       "      <td>0.019263</td>\n",
+       "      <td>0.000095</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "  mesh 10000       energy low [MeV] energy high [MeV] nuclide  \\\n",
-       "           x  y  z                                              \n",
-       "0          1  1  1         0.00e+00          6.25e-07   total   \n",
-       "1          1  1  1         6.25e-07          2.00e+01   total   \n",
-       "2          1  2  1         0.00e+00          6.25e-07   total   \n",
-       "3          1  2  1         6.25e-07          2.00e+01   total   \n",
-       "4          2  1  1         0.00e+00          6.25e-07   total   \n",
-       "5          2  1  1         6.25e-07          2.00e+01   total   \n",
-       "6          2  2  1         0.00e+00          6.25e-07   total   \n",
-       "7          2  2  1         6.25e-07          2.00e+01   total   \n",
+       "   cell  energy low [MeV]  energy high [MeV] nuclide  \\\n",
+       "0     1          0.00e+00           6.25e-07   total   \n",
+       "1     1          6.25e-07           2.00e+01   total   \n",
        "\n",
-       "                                    score     mean std. dev.  \n",
-       "                                                              \n",
-       "0  ((absorption / flux) / (total / flux)) 7.61e-02  7.62e-04  \n",
-       "1  ((absorption / flux) / (total / flux)) 1.92e-02  1.60e-04  \n",
-       "2  ((absorption / flux) / (total / flux)) 7.62e-02  8.00e-04  \n",
-       "3  ((absorption / flux) / (total / flux)) 1.94e-02  1.36e-04  \n",
-       "4  ((absorption / flux) / (total / flux)) 7.62e-02  7.96e-04  \n",
-       "5  ((absorption / flux) / (total / flux)) 1.94e-02  1.54e-04  \n",
-       "6  ((absorption / flux) / (total / flux)) 7.60e-02  6.54e-04  \n",
-       "7  ((absorption / flux) / (total / flux)) 1.91e-02  1.53e-04  "
+       "                                    score     mean  std. dev.  \n",
+       "0  ((absorption / flux) / (total / flux)) 7.61e-02   6.49e-04  \n",
+       "1  ((absorption / flux) / (total / flux)) 1.93e-02   9.46e-05  "
       ]
      },
      "execution_count": 22,
@@ -1316,9 +1009,9 @@
        "<div>\n",
        "<table border=\"1\" class=\"dataframe\">\n",
        "  <thead>\n",
-       "    <tr>\n",
+       "    <tr style=\"text-align: right;\">\n",
        "      <th></th>\n",
-       "      <th colspan=\"3\" halign=\"left\">mesh 10000</th>\n",
+       "      <th>cell</th>\n",
        "      <th>energy low [MeV]</th>\n",
        "      <th>energy high [MeV]</th>\n",
        "      <th>nuclide</th>\n",
@@ -1326,142 +1019,40 @@
        "      <th>mean</th>\n",
        "      <th>std. dev.</th>\n",
        "    </tr>\n",
-       "    <tr>\n",
-       "      <th></th>\n",
-       "      <th>x</th>\n",
-       "      <th>y</th>\n",
-       "      <th>z</th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "    </tr>\n",
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>0.000000e+00</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>total</td>\n",
        "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.923923</td>\n",
-       "      <td>0.009054</td>\n",
+       "      <td>0.923885</td>\n",
+       "      <td>0.007736</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>2.000000e+01</td>\n",
        "      <td>total</td>\n",
        "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.980758</td>\n",
-       "      <td>0.004247</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.923827</td>\n",
-       "      <td>0.009586</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.980628</td>\n",
-       "      <td>0.004411</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>4</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.923817</td>\n",
-       "      <td>0.009436</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.980636</td>\n",
-       "      <td>0.004180</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>6</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.923973</td>\n",
-       "      <td>0.007717</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>7</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>((scatter / flux) / (total / flux))</td>\n",
-       "      <td>0.980926</td>\n",
-       "      <td>0.004623</td>\n",
+       "      <td>0.980737</td>\n",
+       "      <td>0.003737</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "  mesh 10000       energy low [MeV] energy high [MeV] nuclide  \\\n",
-       "           x  y  z                                              \n",
-       "0          1  1  1         0.00e+00          6.25e-07   total   \n",
-       "1          1  1  1         6.25e-07          2.00e+01   total   \n",
-       "2          1  2  1         0.00e+00          6.25e-07   total   \n",
-       "3          1  2  1         6.25e-07          2.00e+01   total   \n",
-       "4          2  1  1         0.00e+00          6.25e-07   total   \n",
-       "5          2  1  1         6.25e-07          2.00e+01   total   \n",
-       "6          2  2  1         0.00e+00          6.25e-07   total   \n",
-       "7          2  2  1         6.25e-07          2.00e+01   total   \n",
+       "   cell  energy low [MeV]  energy high [MeV] nuclide  \\\n",
+       "0     1          0.00e+00           6.25e-07   total   \n",
+       "1     1          6.25e-07           2.00e+01   total   \n",
        "\n",
-       "                                 score     mean std. dev.  \n",
-       "                                                           \n",
-       "0  ((scatter / flux) / (total / flux)) 9.24e-01  9.05e-03  \n",
-       "1  ((scatter / flux) / (total / flux)) 9.81e-01  4.25e-03  \n",
-       "2  ((scatter / flux) / (total / flux)) 9.24e-01  9.59e-03  \n",
-       "3  ((scatter / flux) / (total / flux)) 9.81e-01  4.41e-03  \n",
-       "4  ((scatter / flux) / (total / flux)) 9.24e-01  9.44e-03  \n",
-       "5  ((scatter / flux) / (total / flux)) 9.81e-01  4.18e-03  \n",
-       "6  ((scatter / flux) / (total / flux)) 9.24e-01  7.72e-03  \n",
-       "7  ((scatter / flux) / (total / flux)) 9.81e-01  4.62e-03  "
+       "                                 score     mean  std. dev.  \n",
+       "0  ((scatter / flux) / (total / flux)) 9.24e-01   7.74e-03  \n",
+       "1  ((scatter / flux) / (total / flux)) 9.81e-01   3.74e-03  "
       ]
      },
      "execution_count": 23,
@@ -1497,9 +1088,9 @@
        "<div>\n",
        "<table border=\"1\" class=\"dataframe\">\n",
        "  <thead>\n",
-       "    <tr>\n",
+       "    <tr style=\"text-align: right;\">\n",
        "      <th></th>\n",
-       "      <th colspan=\"3\" halign=\"left\">mesh 10000</th>\n",
+       "      <th>cell</th>\n",
        "      <th>energy low [MeV]</th>\n",
        "      <th>energy high [MeV]</th>\n",
        "      <th>nuclide</th>\n",
@@ -1507,142 +1098,40 @@
        "      <th>mean</th>\n",
        "      <th>std. dev.</th>\n",
        "    </tr>\n",
-       "    <tr>\n",
-       "      <th></th>\n",
-       "      <th>x</th>\n",
-       "      <th>y</th>\n",
-       "      <th>z</th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "      <th></th>\n",
-       "    </tr>\n",
        "  </thead>\n",
        "  <tbody>\n",
        "    <tr>\n",
        "      <th>0</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>0.000000e+00</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>total</td>\n",
        "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
        "      <td>1</td>\n",
-       "      <td>0.009086</td>\n",
+       "      <td>0.007763</td>\n",
        "    </tr>\n",
        "    <tr>\n",
        "      <th>1</th>\n",
        "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
        "      <td>6.250000e-07</td>\n",
        "      <td>2.000000e+01</td>\n",
        "      <td>total</td>\n",
        "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
        "      <td>1</td>\n",
-       "      <td>0.004250</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>2</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.009619</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>3</th>\n",
-       "      <td>1</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.004413</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>4</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.009470</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>5</th>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.004183</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>6</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.000000e+00</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.007745</td>\n",
-       "    </tr>\n",
-       "    <tr>\n",
-       "      <th>7</th>\n",
-       "      <td>2</td>\n",
-       "      <td>2</td>\n",
-       "      <td>1</td>\n",
-       "      <td>6.250000e-07</td>\n",
-       "      <td>2.000000e+01</td>\n",
-       "      <td>total</td>\n",
-       "      <td>(((absorption / flux) / (total / flux)) + ((sc...</td>\n",
-       "      <td>1</td>\n",
-       "      <td>0.004626</td>\n",
+       "      <td>0.003739</td>\n",
        "    </tr>\n",
        "  </tbody>\n",
        "</table>\n",
        "</div>"
       ],
       "text/plain": [
-       "  mesh 10000       energy low [MeV] energy high [MeV] nuclide  \\\n",
-       "           x  y  z                                              \n",
-       "0          1  1  1         0.00e+00          6.25e-07   total   \n",
-       "1          1  1  1         6.25e-07          2.00e+01   total   \n",
-       "2          1  2  1         0.00e+00          6.25e-07   total   \n",
-       "3          1  2  1         6.25e-07          2.00e+01   total   \n",
-       "4          2  1  1         0.00e+00          6.25e-07   total   \n",
-       "5          2  1  1         6.25e-07          2.00e+01   total   \n",
-       "6          2  2  1         0.00e+00          6.25e-07   total   \n",
-       "7          2  2  1         6.25e-07          2.00e+01   total   \n",
+       "   cell  energy low [MeV]  energy high [MeV] nuclide  \\\n",
+       "0     1          0.00e+00           6.25e-07   total   \n",
+       "1     1          6.25e-07           2.00e+01   total   \n",
        "\n",
-       "                                               score     mean std. dev.  \n",
-       "                                                                         \n",
-       "0  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  9.09e-03  \n",
-       "1  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  4.25e-03  \n",
-       "2  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  9.62e-03  \n",
-       "3  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  4.41e-03  \n",
-       "4  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  9.47e-03  \n",
-       "5  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  4.18e-03  \n",
-       "6  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  7.74e-03  \n",
-       "7  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00  4.63e-03  "
+       "                                               score     mean  std. dev.  \n",
+       "0  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00   7.76e-03  \n",
+       "1  (((absorption / flux) / (total / flux)) + ((sc... 1.00e+00   3.74e-03  "
       ]
      },
      "execution_count": 24,