diff --git a/FCCee/ALLEGRO/compact/ALLEGRO_o1_v03/DectDimensions.xml b/FCCee/ALLEGRO/compact/ALLEGRO_o1_v03/DectDimensions.xml
index 7b3a2a305..c09dbea21 100644
--- a/FCCee/ALLEGRO/compact/ALLEGRO_o1_v03/DectDimensions.xml
+++ b/FCCee/ALLEGRO/compact/ALLEGRO_o1_v03/DectDimensions.xml
@@ -48,22 +48,30 @@
     <constant name="DetID_HOMAbsorber"          value=" 19"/>
     <constant name="DetID_LumiCalNoseShield"          value=" 22"/>
     
-    <constant name="BeamPipeWidth"   	value="1.2*mm" />
-    <constant name="BeamPipeWidthFirstCone"   	value="1.0*mm" />
-    <constant name="CentralBeamPipe_zmax" value="12.5*cm"/>
-    <constant name="BePartEnd_z" value="90.0*cm"/>
-    <constant name="SeparatedBeamPipe_z" value="1159.97*mm"/>
-    <constant name="CentralBeamPipe_rmax" value="15.0*mm"/>
-    <constant name="BeamPipeGoldWidth" value="0.005*mm" /> 
+    <!-- BPW: Beam Pipe Width -->
+    <constant name="BPWWall"       value="0.35*mm" />
+    <constant name="BPWCool"       value="1.0*mm" />
+    <constant name="BeamPipeWidth" value="2.0*BPWWall + BPWCool"/>
+
+    <constant name="BeamPipeWidthFirstCone" value="2.0*mm" />
+    <constant name="CentralBeamPipe_zmax" value="9.0*cm"/>          <!-- Shorter central beam pipe -->
+    <constant name="SeparatedBeamPipe_z" value="1190.0*mm"/> <!-- was 1159.97*mm in FCCDetectors/> -->
+    <constant name="CentralBeamPipe_rmax" value="10.0*mm"/>
+    <constant name="ConeBeamPipe_Rmax" value="28.9*mm" />
+    <constant name="BeamPipeGoldWidth" value="0.005*mm" />
     <constant name="BeamPipeGoldTolerance" value="0.001*mm" />  <!-- dummy tolerance, some small non zero value -->
-    
-    <constant name="BigBeamPipe_zmax" value="1120*mm"/>
+    <constant name="BeamPipeConeHalfAngle" value="(ConeBeamPipe_Rmax + BeamPipeWidthFirstCone - CentralBeamPipe_rmax ) / (SeparatedBeamPipe_z - CentralBeamPipe_zmax)" />
+
     <constant name="SeparatedBeamPipe_rmax"  value="15*mm"/>
     <constant name="BeamPipeTantalShieldWidth"  value="15*mm"/>
     <constant name="SideFillerShieldWidth"  value="7*mm"/>
     <constant name="TopFillerShieldWidth"  value="8*mm"/>
     <constant name="BeamPipe_end" value="12500*mm"/>
-    
+
+    <!-- Mike Sullivan's Synch Rad mask -->
+    <constant name="MiddleOfSRMask_z" value="2.1*m" />
+    <constant name="SynchRadMaskSize" value="5*mm" /> <!-- mask tip is at 10 mm from the beamline -->
+    <constant name="mask_epsilon" value="0.001*mm" />    
     
     <constant name="size_x" value="60*mm"/>       
     <constant name="size_y" value="12*mm"/>