diff --git a/README.md b/README.md
index 217def7..5c6ed5e 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,8 @@ Plot showing the cross section versus energy (with error bars):
 | 500 MeV  |  2.194 $\pm$ 0.0161  |  2.203 $\pm$ 0.0044   |
 
 
+In the following, the initial photon energy is set to 0.1 GeV (electron is at rest).
+
 ### Photon final state kinematics
 
 <p align="center">
diff --git a/notebooks/cross-section.ipynb b/notebooks/cross-section.ipynb
index 1136088..d733bf5 100644
--- a/notebooks/cross-section.ipynb
+++ b/notebooks/cross-section.ipynb
@@ -124,7 +124,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.4"
+   "version": "3.10.6"
   }
  },
  "nbformat": 4,
diff --git a/src/compscat/save_events.py b/src/compscat/save_events.py
index f10995d..ea4e1cd 100644
--- a/src/compscat/save_events.py
+++ b/src/compscat/save_events.py
@@ -17,6 +17,7 @@ def to_root(self):
             self.Nevent, self.w_max, self.E
         ).gen_events()
         file = uproot.recreate("MC_compton.root")
+        # factor of 1e6 ensures the result is in KeV
         file["events"] = {
             "Photon_Energy": ph_e * 1e6,
             "Photon_Px": ph_px * 1e6,
@@ -33,7 +34,18 @@ def to_csv(self):
             self.Nevent, self.w_max, self.E
         ).gen_events()
 
-        data = list(zip(ph_e, ph_px, ph_py, ph_pz, el_e, el_px, el_py, el_pz))
+        data = list(
+            zip(
+                ph_e * 1e6,
+                ph_px * 1e6,
+                ph_py * 1e6,
+                ph_pz * 1e6,
+                el_e * 1e6,
+                el_px * 1e6,
+                el_py * 1e6,
+                el_pz * 1e6,
+            )
+        )
 
         column_name = [
             "Photon_Energy",