diff --git a/geometry/positions.xml b/geometry/positions.xml
index 42141f5bd..808c8c184 100644
--- a/geometry/positions.xml
+++ b/geometry/positions.xml
@@ -67,8 +67,10 @@
 <position name="n2atmoVirtualPlane_pos" z="31525.00" unit="mm"/>
 
 <!-- Sieve position -->
-<position name="sieveActualCenter_pos" z="-1895.00" x="200" unit="mm"/>
-<position name="sieveVirtualPlane_pos" z="105.00" unit="mm"/>
+<position name="sieveActualCenter_pos" z="-1795.00" x="200" unit="mm"/>
+<position name="sieveVirtualPlane_pos" z="250.00" unit="mm"/>
+<position name="blockerActualCenter_pos" z="-1795.00" x="-200" unit="mm"/>
+
 
 <!-- Showermax virtual plane detector position -->
 <position name="showerMaxVirtualPlane_pos" z="23920.00-90.00" unit="mm"/>
diff --git a/geometry/target/targetLadder.gdml b/geometry/target/targetLadder.gdml
index 485ae4357..8dea41845 100644
--- a/geometry/target/targetLadder.gdml
+++ b/geometry/target/targetLadder.gdml
@@ -11,7 +11,7 @@
 
 <solids>
   <box name="TargetLadder1_solid" x="200" y="200" z="1300" lunit="mm"/>
-  <box name="TargetLadder2_solid" x="200" y="600" z="1300" lunit="mm"/>
+  <box name="TargetLadder2_solid" x="200" y="700" z="1300" lunit="mm"/>
   <union name="TargetLadder_solid">
     <first ref="TargetLadder1_solid"/>
     <second ref="TargetLadder2_solid"/>
@@ -38,7 +38,7 @@
     <second ref="TargetAlHole_solid"/>
   </subtraction>
 
-  <box name="TargetCFoil_solid" x="25*mm" y="25*mm" z="1*mm"/>
+  <box name="TargetCFoil_solid" x="25*mm" y="25*mm" z="0.254*mm"/>
 
 </solids>
 
@@ -121,7 +121,7 @@
   <volume name="TargetAlDummy4pctUS_logical">
     <materialref ref="G4_Al"/>
     <solidref ref="TargetAlDummy4pct_solid"/>
-    <auxiliary auxtype="TargetSamplingVolume" auxvalue="USAl"/>
+    <auxiliary auxtype="TargetSamplingVolume" auxvalue="DSAl"/>
   </volume>
   <volume name="TargetAlDummy2pctDS_logical">
     <materialref ref="G4_Al"/>
@@ -175,38 +175,71 @@
     <solidref ref="TargetCFoil_solid"/>
     <auxiliary auxtype="TargetSamplingVolume" auxvalue="USC"/>
   </volume>
+
+  <volume name="TargetCFoilMS_logical">
+    <materialref ref="G4_C"/>
+    <solidref ref="TargetCFoil_solid"/>
+    <auxiliary auxtype="TargetSamplingVolume" auxvalue="MSC"/>
+  </volume>
+
   <volume name="TargetCFoilDS_logical">
     <materialref ref="G4_C"/>
     <solidref ref="TargetCFoil_solid"/>
     <auxiliary auxtype="TargetSamplingVolume" auxvalue="DSC"/>
   </volume>
+
+
   <volume name="TargetPositionOptics1_logical">
     <materialref ref="G4_Galactic"/>
     <solidref ref="TargetPosition_solid"/>
-    <physvol>
+    <!--<physvol>
       <volumeref ref="TargetCFoilUS_logical"/>
       <position z="-30*cm"/>
-    </physvol>
+    </physvol>-->
+
     <physvol>
       <volumeref ref="TargetCFoilDS_logical"/>
-      <position z="+60*cm"/>
+      <position z="-62.45*cm"/>
     </physvol>
+
     <auxiliary auxtype="TargetSystem" auxvalue="Optics1"/>
   </volume>
+
+
   <volume name="TargetPositionOptics2_logical">
     <materialref ref="G4_Galactic"/>
     <solidref ref="TargetPosition_solid"/>
-    <physvol>
+
+    <!--<physvol>
       <volumeref ref="TargetCFoilUS_logical"/>
       <position z="-60*cm"/>
-    </physvol>
+    </physvol>-->
+  
     <physvol>
       <volumeref ref="TargetCFoilDS_logical"/>
-      <position z="+30*cm"/>
+      <position z="+62.45*cm"/>
     </physvol>
+
     <auxiliary auxtype="TargetSystem" auxvalue="Optics2"/>
   </volume>
 
+  <volume name="TargetPositionOptics3_logical">
+    <materialref ref="G4_Galactic"/>
+    <solidref ref="TargetPosition_solid"/>
+
+    <!--<physvol>
+      <volumeref ref="TargetCFoilUS_logical"/>
+      <position z="-60*cm"/>
+    </physvol>-->
+  
+    <physvol>
+      <volumeref ref="TargetCFoilDS_logical"/>
+      <position z="+0.0127*cm"/>
+    </physvol>
+
+    <auxiliary auxtype="TargetSystem" auxvalue="Optics3"/>
+  </volume>
+
   <volume name="TargetLadder_logical">
     <materialref ref="G4_Galactic"/>
     <solidref ref="TargetLadder_solid"/>
@@ -255,6 +288,11 @@
       <position y="-63*cm"/>
     </physvol>
 
+    <physvol>
+      <volumeref ref="TargetPositionOptics3_logical"/>
+      <position y="-70*cm"/>
+    </physvol>
+
     <auxiliary auxtype="TargetLadder" auxvalue=""/>
   </volume>
 
diff --git a/geometry/upstream/blocker.gdml b/geometry/upstream/blocker.gdml
new file mode 100644
index 000000000..662726dfa
--- /dev/null
+++ b/geometry/upstream/blocker.gdml
@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<gdml
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:noNamespaceSchemaLocation="http://service-spi.web.cern.ch/service-spi/app/releases/GDML/schema/gdml.xsd">
+
+<define>
+  <!-- Full blocker system dimensions -->
+  <quantity name="blocker_system_inner_radius" type="length" value="1.043" unit="in"/>
+  <quantity name="blocker_system_outer_radius" type="length" value="3.858" unit="in"/>
+  <quantity name="blocker_system_thickness" type="length" value="3.937" unit="in"/>
+
+</define>
+
+<materials>
+</materials>
+
+
+<solids>
+  <!-- Blocker system solid -->
+  <tube name="blocker_system_solid"
+    rmin="blocker_system_inner_radius"
+    rmax="blocker_system_outer_radius"
+    z="blocker_system_thickness"
+    startphi="0" deltaphi="360.0" aunit="deg"
+    />
+</solids>
+
+<structure>
+  <volume name="blocker_system_logic">
+    <materialref ref="G4_W"/>
+    <solidref ref="blocker_system_solid"/>
+    <auxiliary auxtype="Alpha" auxvalue="0.1"/>
+    <auxiliary auxtype="SensDet" auxvalue="sieveDet"/>
+    <auxiliary auxtype="DetType" auxvalue="secondaries"/>
+    <auxiliary auxtype="DetType" auxvalue="boundaryhits"/>
+    <auxiliary auxtype="DetType" auxvalue="lowenergyneutral"/>
+    <auxiliary auxtype="DetNo" auxvalue="1007"/>
+  </volume>
+</structure>
+
+<setup name="blocker_system_world" version="1.0">
+  <world ref="blocker_system_logic"/>
+</setup>
+
+</gdml>
+
+
+
+
diff --git a/geometry/upstream/sieve.gdml b/geometry/upstream/sieve.gdml
index 80775f63a..59ba8e713 100644
--- a/geometry/upstream/sieve.gdml
+++ b/geometry/upstream/sieve.gdml
@@ -5,35 +5,86 @@
 
 <define>
   <!-- Full sieve system dimensions -->
-  <quantity name="sieve_system_inner_radius" type="length" value="1.390" unit="in"/>
-  <quantity name="sieve_system_outer_radius" type="length" value="3.858" unit="in"/>
-  <quantity name="sieve_system_thickness" type="length" value="4.724" unit="in"/>
-
-  <!-- Sieve sector dimensions -->
-  <quantity name="sieve_sector_inner_radius" type="length" value="1.390" unit="in"/>
-  <quantity name="sieve_sector_outer_radius" type="length" value="3.858" unit="in"/>
-  <!-- Radiation length in W is 0.3504 cm [1], so 40 X_0 is about 15 cm.
-   [1] http://pdg.lbl.gov/2019/AtomicNuclearProperties/HTML/tungsten_W.html
-   -->
-  <quantity name="sieve_sector_thickness" type="length" value="4.724" unit="in"/>
-  <quantity name="sieve_sector_angle" type="angle" value="25.7" unit="deg"/>
+  <quantity name="sieve_system_inner_radius" type="length" value="26.5" unit="mm"/>
+  <quantity name="sieve_system_outer_radius" type="length" value="98" unit="mm"/>
+  <quantity name="sieve_system_thickness" type="length" value="100" unit="mm"/>
+
+  <quantity name="sieve_hole_diameter" type="length" value="5" unit="mm"/>
+
 
   <!-- Sieve hole dimensions -->
-  <quantity name="sieve_hole1_diameter" type="length" value="0.5" unit="in"/>
-  <quantity name="sieve_hole1_radial_position" type="length" value="1.8" unit="in"/>
-  <quantity name="sieve_hole1_angular_offset_phi" type="angle" value="0" unit="deg"/>
 
-  <quantity name="sieve_hole2_diameter" type="length" value="0.5" unit="in"/>
-  <quantity name="sieve_hole2_radial_position" type="length" value="3.5" unit="in"/>
-  <quantity name="sieve_hole2_angular_offset_phi" type="angle" value="-5" unit="deg"/>
+  <!-- sector 7 -->
+  <quantity name="sieve_hole71_radial_position" type="length" value="44" unit="mm"/>
+  <quantity name="sieve_hole71_angular_offset_phi" type="angle" value="0 + 360/14 - 360/7" unit="deg"/>
+
+  <quantity name="sieve_hole72_radial_position" type="length" value="68" unit="mm"/>
+  <quantity name="sieve_hole72_angular_offset_phi" type="angle" value="8 + 360/14 - 360/7" unit="deg"/>
+
+  <quantity name="sieve_hole73_radial_position" type="length" value="84.5" unit="mm"/>
+  <quantity name="sieve_hole73_angular_offset_phi" type="angle" value="-8 + 360/14 - 360/7" unit="deg"/>
+
+  <!-- sector 6 -->
+  <quantity name="sieve_hole61_radial_position" type="length" value="39" unit="mm"/>
+  <quantity name="sieve_hole61_angular_offset_phi" type="angle" value="0 - (360/7)*2 + 360/14" unit="deg"/>
+
+  <quantity name="sieve_hole62_radial_position" type="length" value="60" unit="mm"/>
+  <quantity name="sieve_hole62_angular_offset_phi" type="angle" value="8 - (360/7)*2 + 360/14" unit="deg"/>
+
+  <quantity name="sieve_hole63_radial_position" type="length" value="75" unit="mm"/>
+  <quantity name="sieve_hole63_angular_offset_phi" type="angle" value="-8 - (360/7)*2 + 360/14" unit="deg"/>
+
+  <!-- sector 5 -->
+  <quantity name="sieve_hole51_radial_position" type="length" value="56" unit="mm"/>
+  <quantity name="sieve_hole51_angular_offset_phi" type="angle" value="-8 + 360/14 -  (360/7)*3" unit="deg"/>
+
+  <quantity name="sieve_hole52_radial_position" type="length" value="56" unit="mm"/>
+  <quantity name="sieve_hole52_angular_offset_phi" type="angle" value="8 + 360/14 -  (360/7)*3" unit="deg"/>
+
+  <quantity name="sieve_hole53_radial_position" type="length" value="80" unit="mm"/>
+  <quantity name="sieve_hole53_angular_offset_phi" type="angle" value="0 + 360/14 -  (360/7)*3" unit="deg"/>
+
+  <!-- sector 4 -->
+  <quantity name="sieve_hole41_radial_position" type="length" value="50" unit="mm"/>
+  <quantity name="sieve_hole41_angular_offset_phi" type="angle" value="-8 + 360/14 - (360/7)*4" unit="deg"/>
+
+  <quantity name="sieve_hole42_radial_position" type="length" value="60" unit="mm"/>
+  <quantity name="sieve_hole42_angular_offset_phi" type="angle" value="0 + 360/14 - (360/7)*4" unit="deg"/>
+
+  <quantity name="sieve_hole43_radial_position" type="length" value="70" unit="mm"/>
+  <quantity name="sieve_hole43_angular_offset_phi" type="angle" value="8 + 360/14 - (360/7)*4" unit="deg"/>
+
+  <!-- sector 3 -->
+  <quantity name="sieve_hole31_radial_position" type="length" value="39" unit="mm"/>
+  <quantity name="sieve_hole31_angular_offset_phi" type="angle" value="0 + 360/14 - (360/7)*5" unit="deg"/>
+
+  <quantity name="sieve_hole32_radial_position" type="length" value="63" unit="mm"/>
+  <quantity name="sieve_hole32_angular_offset_phi" type="angle" value="8 + 360/14 - (360/7)*5" unit="deg"/>
+
+  <quantity name="sieve_hole33_radial_position" type="length" value="80" unit="mm"/>
+  <quantity name="sieve_hole33_angular_offset_phi" type="angle" value="-8 + 360/14 - (360/7)*5" unit="deg"/>
+
+  <!-- sector 2 -->
+  <quantity name="sieve_hole21_radial_position" type="length" value="50" unit="mm"/>
+  <quantity name="sieve_hole21_angular_offset_phi" type="angle" value="-8 + 360/14 - (360/7)*6" unit="deg"/>
+
+  <quantity name="sieve_hole22_radial_position" type="length" value="56" unit="mm"/>
+  <quantity name="sieve_hole22_angular_offset_phi" type="angle" value="8 + 360/14 - (360/7)*6" unit="deg"/>
+
+ <quantity name="sieve_hole23_radial_position" type="length" value="75" unit="mm"/>
+  <quantity name="sieve_hole23_angular_offset_phi" type="angle" value="0 + 360/14 - (360/7)*6" unit="deg"/>
+
+  <!-- sector 1 -->
+  <quantity name="sieve_hole11_radial_position" type="length" value="35" unit="mm"/>
+  <quantity name="sieve_hole11_angular_offset_phi" type="angle" value="0 + 360/14 - (360/7)*7" unit="deg"/>
+
+  <quantity name="sieve_hole13_radial_position" type="length" value="84.5" unit="mm"/>
+  <quantity name="sieve_hole13_angular_offset_phi" type="angle" value="8 + 360/14 - (360/7)*7" unit="deg"/>
+  
+  <quantity name="sieve_hole12_radial_position" type="length" value="58" unit="mm"/>
+  <quantity name="sieve_hole12_angular_offset_phi" type="angle" value="-8 + 360/14 - (360/7)*7" unit="deg"/>
 
-  <quantity name="sieve_hole3_diameter" type="length" value="0.5" unit="in"/>
-  <quantity name="sieve_hole3_radial_position" type="length" value="2.6" unit="in"/>
-  <quantity name="sieve_hole3_angular_offset_phi" type="angle" value="2.5" unit="deg"/>
-  <quantity name="sieve_hole3_axis_theta" type="angle" value="2.5" unit="deg"/>
-  <quantity name="sieve_hole3_axis_phi" type="angle" value="0" unit="deg"/>
 
-  <variable name="i" value="1"/>
 </define>
 
 <materials>
@@ -41,7 +92,7 @@
 
 
 <solids>
-  <!-- Sieve system solid -->
+ 
   <tube name="sieve_system_solid"
     rmin="sieve_system_inner_radius"
     rmax="sieve_system_outer_radius"
@@ -49,128 +100,210 @@
     startphi="0" deltaphi="360.0" aunit="deg"
     />
 
-  <!-- Sieve sector solid -->
-  <tube name="sieve_sector_solid"
-    rmin="sieve_sector_inner_radius"
-    rmax="sieve_sector_outer_radius"
-    z="sieve_sector_thickness"
-    startphi="-sieve_sector_angle/2" deltaphi="sieve_sector_angle"
-    />
-
   <!-- Sieve hole solids -->
-  <tube name="sieve_hole1_solid"
-    rmin="0."
-    rmax="sieve_hole1_diameter/2"
-    z="sieve_sector_thickness"
-    startphi="0" deltaphi="360.0" aunit="deg"
-    />
-  <tube name="sieve_hole2_solid"
-    rmin="0."
-    rmax="sieve_hole2_diameter/2"
-    z="sieve_sector_thickness"
-    startphi="0" deltaphi="360.0" aunit="deg"
-    />
-  <!-- Support for non-zero sieve_hole_axis_theta and sieve_hole_axis_phi
-    requires implementation of solid with cutTube, but this is slower so avoid
-    if not necessary -->
-  <cutTube name="sieve_hole3_solid"
+  <tube name="sieve_hole_solid"
     rmin="0."
-    rmax="sieve_hole3_diameter/2"
-    z="sieve_sector_thickness/cos(sieve_hole3_axis_theta)"
+    rmax="sieve_hole_diameter/2"
+    z="sieve_system_thickness+2"
     startphi="0" deltaphi="360.0" aunit="deg"
-    lowX="-sin(-sieve_hole3_axis_theta)*cos(-sieve_hole3_axis_phi)"
-    lowY="-sin(-sieve_hole3_axis_theta)*sin(-sieve_hole3_axis_phi)"
-    lowZ="-cos(-sieve_hole3_axis_theta)"
-    highX="sin(-sieve_hole3_axis_theta)*cos(-sieve_hole3_axis_phi)"
-    highY="sin(-sieve_hole3_axis_theta)*sin(-sieve_hole3_axis_phi)"
-    highZ="cos(-sieve_hole3_axis_theta)"
     />
+
 </solids>
 
 <structure>
-  <!-- Define the holes as detectors to enable mc-truth analysis where
-    one requires that the track went through a specific sieve hole -->
-  <volume name="sieve_hole1_logic">
-    <materialref ref="G4_Galactic"/>
-    <solidref ref="sieve_hole1_solid"/>
-    <auxiliary auxtype="Color" auxvalue="magenta"/>
-    <auxiliary auxtype="Alpha" auxvalue="0.1"/>
-    <auxiliary auxtype="SensDet" auxvalue="sieveDet"/>
-    <auxiliary auxtype="DetType" auxvalue="secondaries"/>
-    <auxiliary auxtype="DetType" auxvalue="boundaryhits"/>
-    <auxiliary auxtype="DetType" auxvalue="lowenergyneutral"/>
-    <auxiliary auxtype="DetNo" auxvalue="1001"/>
-  </volume>
-  <volume name="sieve_hole2_logic">
+  
+  <volume name="sieve_hole_logic">
     <materialref ref="G4_Galactic"/>
-    <solidref ref="sieve_hole2_solid"/>
+    <solidref ref="sieve_hole_solid"/>
     <auxiliary auxtype="Color" auxvalue="magenta"/>
     <auxiliary auxtype="Alpha" auxvalue="0.1"/>
     <auxiliary auxtype="SensDet" auxvalue="sieveDet"/>
     <auxiliary auxtype="DetType" auxvalue="secondaries"/>
     <auxiliary auxtype="DetType" auxvalue="boundaryhits"/>
     <auxiliary auxtype="DetType" auxvalue="lowenergyneutral"/>
-    <auxiliary auxtype="DetNo" auxvalue="1002"/>
   </volume>
-  <volume name="sieve_hole3_logic">
-    <materialref ref="G4_Galactic"/>
-    <solidref ref="sieve_hole3_solid"/>
-    <auxiliary auxtype="Color" auxvalue="magenta"/>
-    <auxiliary auxtype="Alpha" auxvalue="0.1"/>
+  
+  <volume name="sieve_system_logic">
+    <materialref ref="CW90"/>
+    <solidref ref="sieve_system_solid"/>
+    <auxiliary auxtype="Alpha" auxvalue="0.8"/>
     <auxiliary auxtype="SensDet" auxvalue="sieveDet"/>
     <auxiliary auxtype="DetType" auxvalue="secondaries"/>
     <auxiliary auxtype="DetType" auxvalue="boundaryhits"/>
     <auxiliary auxtype="DetType" auxvalue="lowenergyneutral"/>
-    <auxiliary auxtype="DetNo" auxvalue="1003"/>
-  </volume>
 
-  <!-- Place the holes inside the sector volume -->
-  <volume name="sieve_sector_logic">
-    <materialref ref="G4_W"/>
-    <solidref ref="sieve_sector_solid"/>
-    <physvol name="sieve_hole1_physical">
-      <volumeref ref="sieve_hole1_logic"/>
-      <position x="sieve_hole1_radial_position"/>
+    <physvol name="sieve_hole71_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole71_radial_position*cos(sieve_hole71_angular_offset_phi)"
+        y="sieve_hole71_radial_position*sin(sieve_hole71_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole72_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole72_radial_position*cos(sieve_hole72_angular_offset_phi)"
+        y="sieve_hole72_radial_position*sin(sieve_hole72_angular_offset_phi)"
+        />
+
     </physvol>
 
-    <physvol name="sieve_hole2_physical">
-      <volumeref ref="sieve_hole2_logic"/>
+ <physvol name="sieve_hole73_physical">
+      <volumeref ref="sieve_hole_logic"/>
       <position
-        x="sieve_hole2_radial_position*cos(sieve_hole2_angular_offset_phi)"
-        y="sieve_hole2_radial_position*sin(sieve_hole2_angular_offset_phi)"
+        x="sieve_hole73_radial_position*cos(sieve_hole73_angular_offset_phi)"
+        y="sieve_hole73_radial_position*sin(sieve_hole73_angular_offset_phi)"
         />
     </physvol>
 
-    <physvol name="sieve_hole3_physical">
-      <volumeref ref="sieve_hole3_logic"/>
+   <physvol name="sieve_hole61_physical">
+      <volumeref ref="sieve_hole_logic"/>
       <position
-        x="sieve_hole3_radial_position*cos(sieve_hole3_angular_offset_phi)"
-        y="sieve_hole3_radial_position*sin(sieve_hole3_angular_offset_phi)"
+        x="sieve_hole61_radial_position*cos(sieve_hole61_angular_offset_phi)"
+        y="sieve_hole61_radial_position*sin(sieve_hole61_angular_offset_phi)"
         />
-      <rotation
-        y="-(sieve_hole3_axis_theta)"
+    </physvol>
+
+    <physvol name="sieve_hole62_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole62_radial_position*cos(sieve_hole62_angular_offset_phi)"
+        y="sieve_hole62_radial_position*sin(sieve_hole62_angular_offset_phi)"
         />
     </physvol>
-  </volume>
 
-  <!-- Place the sector volumes around the ring -->
-  <volume name="sieve_system_logic">
-    <materialref ref="G4_Galactic"/>
-    <solidref ref="sieve_system_solid"/>
-    <auxiliary auxtype="Alpha" auxvalue="0.1"/>
-    <auxiliary auxtype="SensDet" auxvalue="sieveDet"/>
-    <auxiliary auxtype="DetType" auxvalue="secondaries"/>
-    <auxiliary auxtype="DetType" auxvalue="boundaryhits"/>
-    <auxiliary auxtype="DetType" auxvalue="lowenergyneutral"/>
-    <auxiliary auxtype="DetNo" auxvalue="1000"/>
-    <loop for="i" from="1" to="7" step="1">
-      <physvol name="sieve_sector_physical[i]">
-        <volumeref ref="sieve_sector_logic"/>
-        <rotation unit="deg"
-          z="360.0/14.0+360.0/7.0*(i-1)"
-          />
-      </physvol>
-    </loop>
+   <physvol name="sieve_hole63_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole63_radial_position*cos(sieve_hole63_angular_offset_phi)"
+        y="sieve_hole63_radial_position*sin(sieve_hole63_angular_offset_phi)"
+        />
+    </physvol>
+
+   <physvol name="sieve_hole51_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole51_radial_position*cos(sieve_hole51_angular_offset_phi)"
+        y="sieve_hole51_radial_position*sin(sieve_hole51_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole52_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole52_radial_position*cos(sieve_hole52_angular_offset_phi)"
+        y="sieve_hole52_radial_position*sin(sieve_hole52_angular_offset_phi)"
+        />
+    </physvol>
+    
+    <physvol name="sieve_hole53_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole53_radial_position*cos(sieve_hole53_angular_offset_phi)"
+        y="sieve_hole53_radial_position*sin(sieve_hole53_angular_offset_phi)"
+        />
+    </physvol>
+
+  <physvol name="sieve_hole41_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole41_radial_position*cos(sieve_hole41_angular_offset_phi)"
+        y="sieve_hole41_radial_position*sin(sieve_hole41_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole42_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole42_radial_position*cos(sieve_hole42_angular_offset_phi)"
+        y="sieve_hole42_radial_position*sin(sieve_hole42_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole43_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole43_radial_position*cos(sieve_hole43_angular_offset_phi)"
+        y="sieve_hole43_radial_position*sin(sieve_hole43_angular_offset_phi)"
+        />
+    </physvol>
+
+  <physvol name="sieve_hole31_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole31_radial_position*cos(sieve_hole31_angular_offset_phi)"
+        y="sieve_hole31_radial_position*sin(sieve_hole31_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole32_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole32_radial_position*cos(sieve_hole32_angular_offset_phi)"
+        y="sieve_hole32_radial_position*sin(sieve_hole32_angular_offset_phi)"
+        />
+    </physvol>
+
+  <physvol name="sieve_hole33_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole33_radial_position*cos(sieve_hole33_angular_offset_phi)"
+        y="sieve_hole33_radial_position*sin(sieve_hole33_angular_offset_phi)"
+        />
+    </physvol>
+
+  <physvol name="sieve_hole21_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole21_radial_position*cos(sieve_hole21_angular_offset_phi)"
+        y="sieve_hole21_radial_position*sin(sieve_hole21_angular_offset_phi)"
+        />
+    </physvol>
+
+
+  <physvol name="sieve_hole22_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole22_radial_position*cos(sieve_hole22_angular_offset_phi)"
+        y="sieve_hole22_radial_position*sin(sieve_hole22_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole23_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole23_radial_position*cos(sieve_hole23_angular_offset_phi)"
+        y="sieve_hole23_radial_position*sin(sieve_hole23_angular_offset_phi)"
+        />
+    </physvol>
+
+  <physvol name="sieve_hole11_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole11_radial_position*cos(sieve_hole11_angular_offset_phi)"
+        y="sieve_hole11_radial_position*sin(sieve_hole11_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole12_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole12_radial_position*cos(sieve_hole12_angular_offset_phi)"
+        y="sieve_hole12_radial_position*sin(sieve_hole12_angular_offset_phi)"
+        />
+    </physvol>
+
+    <physvol name="sieve_hole13_physical">
+      <volumeref ref="sieve_hole_logic"/>
+      <position
+        x="sieve_hole13_radial_position*cos(sieve_hole13_angular_offset_phi)"
+        y="sieve_hole13_radial_position*sin(sieve_hole13_angular_offset_phi)"
+        />
+    </physvol>
+
+
+   
   </volume>
 </structure>
 
diff --git a/geometry/upstream/upstreamTorusRegion.gdml b/geometry/upstream/upstreamTorusRegion.gdml
index 298df3c08..a8dee3860 100644
--- a/geometry/upstream/upstreamTorusRegion.gdml
+++ b/geometry/upstream/upstreamTorusRegion.gdml
@@ -1644,6 +1644,11 @@
         <positionref ref="sieveActualCenter_pos"/>
       </physvol>
 
+      <physvol name="USblocker">
+        <file name= "upstream/blocker.gdml"/>
+        <positionref ref="blockerActualCenter_pos"/>
+      </physvol>
+
       <physvol name="UScoil">
         <file name= "upstream/upstreamToroid.gdml"/>
       </physvol>
diff --git a/macros/blocker/blockerTest_100.mac b/macros/blocker/blockerTest_100.mac
new file mode 100644
index 000000000..19f7b834e
--- /dev/null
+++ b/macros/blocker/blockerTest_100.mac
@@ -0,0 +1,44 @@
+/remoll/geometry/setfile geometry/mollerMother.gdml
+/remoll/parallel/setfile geometry/mollerParallel.gdml
+
+/remoll/physlist/parallel/enable 
+
+# Enable optical physics
+/remoll/physlist/optical/enable
+
+# This must be explicitly called
+/run/initialize
+
+/remoll/printgeometry true
+
+/control/execute macros/load_magnetic_fieldmaps.mac
+
+# Raster and initial angle stuff
+/remoll/oldras true
+/remoll/rasx 5 mm
+/remoll/rasy 5 mm
+
+#/remoll/evgen/set moller
+#/remoll/evgen/set elastic 
+#/remoll/evgen/set inelastic 
+/remoll/evgen/set pion
+#/remoll/piontype pi+
+#/remoll/evgen/set pion_LUND
+#/remoll/evgen/set inelasticAl
+#/remoll/evgen/set quasielasticAl
+#/remoll/evgen/set elasticAl
+#/remoll/evgen/set external
+
+/remoll/beamene 11 GeV
+/remoll/beamcurr 65 microampere
+
+/control/execute macros/blocker/blocker_in.mac
+
+/remoll/SD/disable_all
+/remoll/SD/enable 29 #DS pion det
+/remoll/SD/enable 1006 #sieve (secondaries)
+/remoll/SD/enable 1007 #blocker
+
+/process/list
+
+/run/beamOn 100
diff --git a/macros/blocker/blocker_in.mac b/macros/blocker/blocker_in.mac
new file mode 100644
index 000000000..8dddf1de0
--- /dev/null
+++ b/macros/blocker/blocker_in.mac
@@ -0,0 +1,2 @@
+# Move the blocker 200 mm to beam axis
+/remoll/geometry/relative_position USblocker (200,0,0)
diff --git a/macros/blocker/blocker_out.mac b/macros/blocker/blocker_out.mac
new file mode 100644
index 000000000..04a2e1cea
--- /dev/null
+++ b/macros/blocker/blocker_out.mac
@@ -0,0 +1,2 @@
+# Move the blocker 200 mm off axis
+/remoll/geometry/relative_position USblocker (-200,0,0)
diff --git a/macros/target/Optics2.mac b/macros/target/Optics2.mac
index 2f0b72c07..ca3bc05de 100644
--- a/macros/target/Optics2.mac
+++ b/macros/target/Optics2.mac
@@ -1,3 +1,3 @@
 /remoll/geometry/absolute_position targetLadder (0,630,0)
 /remoll/target/mother Optics2
-/remoll/target/volume USC
+/remoll/target/volume DSC
diff --git a/macros/target/Optics3.mac b/macros/target/Optics3.mac
new file mode 100644
index 000000000..f7bd47078
--- /dev/null
+++ b/macros/target/Optics3.mac
@@ -0,0 +1,3 @@
+/remoll/geometry/absolute_position targetLadder (0,700,0)
+/remoll/target/mother Optics3
+/remoll/target/volume DSC