diff --git a/src/classes/PRunSingleHisto.cpp b/src/classes/PRunSingleHisto.cpp
index 72f16bddb..1571a0311 100644
--- a/src/classes/PRunSingleHisto.cpp
+++ b/src/classes/PRunSingleHisto.cpp
@@ -2274,7 +2274,7 @@ void PRunSingleHisto::EstimateN0()
  * Pulsed beams have time-dependent backgrounds from:
  * - Flash (instantaneous background from beam pulse)
  * - Prompt particles
- * - Slow neutron background
+ * - Pion background
  *
  * Averaging over complete beam cycles ensures unbiased background estimates
  * by including all phases of the pulsed structure.