diff --git a/src/py2dmat/solver/lib_make_convolution.py b/src/py2dmat/solver/lib_make_convolution.py
index ae05e16a..51299029 100644
--- a/src/py2dmat/solver/lib_make_convolution.py
+++ b/src/py2dmat/solver/lib_make_convolution.py
@@ -1,7 +1,8 @@
 import numpy as np
 import sys
+import copy
 
-def calc(RC_data_org, RC_data_cnv, number_of_beams, number_of_glancing_angles, omega, verbose_mode):
+def calc(RC_data_org, number_of_beams, number_of_glancing_angles, omega, verbose_mode):
 
     sigma = 0.5 * omega / (np.sqrt(2.0*np.log(2.0)))
 
@@ -10,12 +11,16 @@ def g(x):
 
         return g
 
+    RC_data_cnv = np.zeros((number_of_glancing_angles, number_of_beams+1))
+    #copy glancing angle
+    RC_data_cnv[:,0] = copy.deepcopy(RC_data_org[:,0])
+
     angle_interval = RC_data_org[1,0] - RC_data_org[0,0]
 
     if verbose_mode:
        print("RC_data_org =\n",RC_data_org) 
        print("RC_data_cnv =\n",RC_data_cnv) 
-       print('angle_ interval=', angle_interval)
+       print('angle_interval=', angle_interval)
 
     for beam_index in range(number_of_beams):
         for index in range(number_of_glancing_angles):
diff --git a/src/py2dmat/solver/sim_trhepd_rheed_mb_connect.py b/src/py2dmat/solver/sim_trhepd_rheed_mb_connect.py
index 33bf6afc..65cdcf59 100644
--- a/src/py2dmat/solver/sim_trhepd_rheed_mb_connect.py
+++ b/src/py2dmat/solver/sim_trhepd_rheed_mb_connect.py
@@ -759,7 +759,6 @@ def _calc_I_from_file(self):
             # Define the array for the rocking curve data.
             # Note the components with (beam-index)=0 are the degree data
             RC_data_org = np.zeros((number_of_glancing_angles, number_of_beams+1))
-            RC_data_cnv = np.zeros((number_of_glancing_angles, number_of_beams+1))
 
             for g_angle_index in range(number_of_glancing_angles):
                 line_index = number_of_header_lines + g_angle_index
@@ -769,7 +768,6 @@ def _calc_I_from_file(self):
                 data = line.split()
             #   print(data)
                 RC_data_org[g_angle_index,0]=float(data[0])
-                RC_data_cnv[g_angle_index,0]=float(data[0])
                 for beam_index in range(number_of_beams):
                     RC_data_org[g_angle_index, beam_index+1] = data[beam_index+1]
 
@@ -780,7 +778,7 @@ def _calc_I_from_file(self):
             if self.log_mode : time_sta = time.perf_counter() 
             verbose_mode = False
             data_convolution = lib_make_convolution.calc(
-                    RC_data_org, RC_data_cnv, number_of_beams, number_of_glancing_angles, self.omega, verbose_mode
+                    RC_data_org, number_of_beams, number_of_glancing_angles, self.omega, verbose_mode
                         ) 
 
             self.all_convolution_I_calculated_list_normalized = []