diff --git a/compact/tof_barrel.xml b/compact/tof_barrel.xml
index 68ecff500662332c0a6a9a066fc8015aae5c7988..94633381d09bbd815623350a65f9a15c14773703 100644
--- a/compact/tof_barrel.xml
+++ b/compact/tof_barrel.xml
@@ -1,6 +1,24 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <lccdd>
   <define>
+      
+      <constant name="VertexTrackerRadius1" value="46*mm"/>
+      <constant name="VertexTrackerRadius2" value="54*mm"/>
+      <constant name="VertexTrackerRadius3" value="62*mm"/>
+      <constant name="VertexTrackerRadius4" value="70*mm"/>
+      <constant name="VertexTrackerRadius5" value="80*mm"/>
+      <constant name="VertexTrackerRadius6" value="95*mm"/>
+      <constant name="VertexTrackerRadius7" value="450*mm"/>
+      <constant name="VertexTrackerRadius8" value="465*mm"/>
+      <constant name="VertexTrackerNModules1" value="14"/>
+      <constant name="VertexTrackerNModules2" value="18"/>
+      <constant name="VertexTrackerNModules3" value="22"/>
+      <constant name="VertexTrackerNModules4" value="24"/>
+      <constant name="VertexTrackerNModules5" value="28"/>
+      <constant name="VertexTrackerNModules6" value="32"/>
+      <constant name="VertexTrackerNModules7" value="36"/>
+      <constant name="VertexTrackerNModules8" value="40"/>
+
 
       <constant name="BarrelTOFRadius"         value=" 45*cm"/>
       <constant name="BarrelTOFTotalLength"    value="120*cm"/>
@@ -94,14 +112,19 @@
                          outer_r="BarrelTOFRadius+10*mm" z_length="BarrelTOFTotalLength"/>
         <rphi_layout phi_tilt="10.0*degree" nphi="BarrelTOFModulesNPhi" phi0="0.0" rc="BarrelTOFRadius" dr="0.0 * mm"/>
         <z_layout dr="0.0 * mm" z0="0.0 * mm" nz="BarrelTOFModulesNZ"/>
-      </layer>-->
+      </layer>
 
       <layer module="BarrelTOFModule_Layer" id="2" vis="GreenVis">
         <barrel_envelope inner_r="BarrelTOFRadius" outer_r="BarrelTOFRadius + 30.0*mm" z_length="BarrelTOFTotalLength +1.0*mm "/>
         <rphi_layout phi_tilt="0.17506" nphi="BarrelTOFModulesNPhi" phi0="0." rc="BarrelTOFRadius + 10.0 * mm" dr="0.0 * mm"/>
         <z_layout dr="4.0 * mm"
                   z0="(BarrelTOFTotalLength - BarrelTOFModuleLength)/2"
-                  nz="BarrelTOFModulesNZ"/>
+                  nz="BarrelTOFModulesNZ"/>-->
+      <layer module="UFSD" id="8" vis="SiVertexVis">
+        <barrel_envelope inner_r="(VertexTrackerRadius7+VertexTrackerRadius8)/2"
+                         outer_r="VertexTrackerRadius8+5*mm" z_length="VertexTrackerBarrel_length"/>
+        <rphi_layout phi_tilt="10.0*degree" nphi="VertexTrackerNModules8" phi0="0.0" rc="VertexTrackerRadius8" dr="0.0 * mm"/>
+        <z_layout dr="0.0 * mm" z0="0.0 * mm" nz="1"/>
       </layer>
     </detector>