diff --git a/Model.py b/Model.py
index c4b4a12b1613e7717a4d4764dab11a736654dac2..e78d0264511328922e59aea51e66ecb81e7867dc 100644
--- a/Model.py
+++ b/Model.py
@@ -641,7 +641,15 @@ def DRM(Q, Q_0, G, mu, lbda, sigma_0, sigma_1, tau_Ap, p_Ap, DCR, tau, tau_R, t_
     
     Pns = np.zeros((int(k_max), int(k_max)))
     
-    alpha = P_Ap(tau_R, tau_Ap, t_gate, p_Ap)
+    # alpha is either one of two things:
+    # the total probability of an afterpulse occuring within the gate  
+    
+    alpha = p_Ap
+
+    # Or the probability that an electron-hole pair is produced in the silicon bulk.  
+    # alpha = P_Ap(tau_R, tau_Ap, t_gate, p_Ap)
+    # 
+    # To replicate the results in the paper, please keep this variable as it is. 
     
     dp0dQs = np.vstack([norm.pdf(k_pad, loc=_k, scale=sigmak(_k, sigma_0/G, sigma_1/G)) for _k in k_pg])