LDMX-Software · Layan-Sarayra · Nov 6, 2025 · Nov 11, 2025 · Nov 21, 2025 · Nov 21, 2025
diff --git a/DetDescr/python/EcalGeometry.py b/DetDescr/python/EcalGeometry.py
@@ -174,6 +174,7 @@ def reduced_v2() :
         # shift by a single cell diameter
         eg.layer_shift_x = 2*eg.moduleMinR / eg.nCellRHeight
         return eg
+
 
     def reduced_v3() :
         eg = EcalGeometry(detectors_valid = ["ldmx-reduced-v3"],

diff --git a/DetDescr/python/HcalGeometry.py b/DetDescr/python/HcalGeometry.py
@@ -487,5 +487,5 @@ def make_v14(self):
         ]
         # added the reduced geometry temporarily, for the final geometry
         # we should have a new function "reduced()" with the prototype geom
-        self.v14.detectors_valid = ["ldmx-det-v14", "ldmx-det-v14.*", "ldmx-reduced", "ldmx-reduced-v2", "ldmx-reduced-v3","ldmx-lyso-r4-v15", "ldmx-lyso-r4-v15.*", "ldmx-det-v15","ldmx-det-v15.*"]
+        self.v14.detectors_valid = ["ldmx-det-v14", "ldmx-det-v14.*", "ldmx-reduced", "ldmx-reduced-v2", "ldmx-lyso-r4-v15", "ldmx-lyso-r4-v15.*", "ldmx-det-v15","ldmx-det-v15.*"]
         self.v14.y_offset = 19.05
diff --git a/Detectors/data/ldmx-det-v15-8gev/constants.gdml b/Detectors/data/ldmx-det-v15-8gev/constants.gdml
@@ -149,6 +149,15 @@
 <constant name="trigger_pad2_actual_z"
     value="ts_center_z + (trig_scint_area_envelope_z/2 - trigger_pad_thickness/2)" />
 
+<!-- Light-pipe bar dimensions -->
+<constant name="light_pipe_dx" value="36.24*mm"/>
+<constant name="light_pipe_dy" value="2*mm"/>
+<constant name="light_pipe_thickness" value="2*mm"/>
+
+<!-- Light pipe positions relative to TS pads -->
+<constant name="light_pipe_pad1_z_offset" value="-(trigger_pad_bar_thickness/2 + light_pipe_thickness/2)"/>
+<constant name="light_pipe_pad2_z_offset" value="-(trigger_pad_bar_thickness/2 + light_pipe_thickness/2)"/>
+<constant name="light_pipe_pad3_z_offset" value="trigger_pad_bar_thickness/2 + light_pipe_thickness/2"/>
 
 <!--
    HCal

diff --git a/Detectors/data/ldmx-det-v15-8gev/detector.gdml b/Detectors/data/ldmx-det-v15-8gev/detector.gdml
@@ -36,6 +36,10 @@
          x = y = z = 0 mm.     
     -->
     <position name="trig_scint_pos" x="0.0" y="0.0" z="trig_scint_pos_z"/>
+
+    <!-- Light pipe module position  -->
+    <position name="light_pipe_pos" x="0.0" y="0.0" z="trig_scint_pos_z"/>
+
     <position name="tagger_pos" x="0.0" y="0.0" z="tagger_pos_z"/>
     <position name="recoil_pos" x="0.0" y="0.0" z="recoil_pos_z"/>
     <position name="em_calorimeter_pos"
@@ -94,11 +98,16 @@
         <positionref ref="hadron_calorimeter_pos"/> 
         <rotationref ref="identity"/> 
       </physvol>
-      <physvol>
+      <physvol copynumber="8">
         <file name="magnet.gdml"/> 
         <positionref ref="magnet_pos"/> 
         <rotationref ref="identity"/> 
       </physvol>
+      <physvol copynumber="9">
+        <file name="ts_light_pipes.gdml"/>
+        <positionref ref="light_pipe_pos"/>
+        <rotationref ref="identity"/>
+      </physvol>
       <auxiliary auxtype="DetElem" auxvalue="Top"/>
     </volume>
   </structure>
@@ -220,6 +229,9 @@
       <auxiliary auxtype="Visible" auxvalue="false"/>
       <auxiliary auxtype="LineWidth" auxvalue="1.0"/>
     </auxiliary>  
+    <auxiliary auxtype="Region" auxvalue="light_pipe">
+      <auxiliary auxtype="StoreTrajectories" auxvalue="true"/>
+    </auxiliary>
   </userinfo>  
 
   <setup name="Default" version="1.0">

diff --git a/Detectors/data/ldmx-det-v15-8gev/magnet.gdml b/Detectors/data/ldmx-det-v15-8gev/magnet.gdml
@@ -2,9 +2,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<gdml xmlns:gdml="http://cern.ch/2001/Schemas/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" >
+<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>
 
         &constants; 

diff --git a/Detectors/data/ldmx-det-v15-8gev/recoil.gdml b/Detectors/data/ldmx-det-v15-8gev/recoil.gdml
@@ -2,8 +2,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<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">
+<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>      
     &constants;
 

diff --git a/Detectors/data/ldmx-det-v15-8gev/scoring_planes.gdml b/Detectors/data/ldmx-det-v15-8gev/scoring_planes.gdml
@@ -2,8 +2,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<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">
+<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>
 

diff --git a/Detectors/data/ldmx-det-v15-8gev/tagger.gdml b/Detectors/data/ldmx-det-v15-8gev/tagger.gdml
@@ -3,9 +3,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<gdml xmlns:gdml="http://cern.ch/2001/Schemas/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">
+<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>
     &constants;  
 

diff --git a/Detectors/data/ldmx-det-v15-8gev/target.gdml b/Detectors/data/ldmx-det-v15-8gev/target.gdml
@@ -2,9 +2,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<gdml xmlns:gdml="http://cern.ch/2001/Schemas/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" >
+<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>
 

diff --git a/Detectors/data/ldmx-det-v15-8gev/trig_scint.gdml b/Detectors/data/ldmx-det-v15-8gev/trig_scint.gdml
@@ -2,9 +2,8 @@
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
 ]>
-<gdml xmlns:gdml="http://cern.ch/2001/Schemas/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" >
+<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>
 

diff --git a/Detectors/data/ldmx-reduced-v3/constants.gdml b/Detectors/data/ldmx-reduced-v3/constants.gdml
@@ -11,21 +11,52 @@
 <!-- 
     Target
 --> 
+<!-- LYSO for ESA -->
+
 <!-- position -->
-<constant name="target_z" value="0.0*mm" />
-<!-- Tungsten X0 = .3504 cm.  Target thickeness = .1X0 -->
-<constant name="target_thickness" value="0.3504*mm" />
+<constant name="target_z" value="0.0" />
 <!-- Target dimensions -->
-<constant name="target_dim_x" value="4.0*cm"  />
-<constant name="target_dim_y" value="10.0*cm" />
+  <!-- target bar-->
+<constant name="target_bar_dx" value="30" />
+<constant name="target_bar_dy" value="3.0" />
+<constant name="target_bar_thickness" value="0.6" />
+<constant name="target_bar_gap" value="0.2" />
+
+  <!-- target array1-->
+<constant name="number_of_target_bars1" value="16" />
+<constant name="target_array1_dx" value="target_bar_dx" />
+<constant name="target_array1_dy" value="number_of_target_bars1 * target_bar_dy + (number_of_target_bars1 - 1) * target_bar_gap" />
+<constant name="target_array1_thickness" value="target_bar_thickness" />
+
+  <!-- target array2-->
+<constant name="number_of_target_bars2" value="17" />
+<constant name="target_array2_dx" value="target_bar_dx" />
+<constant name="target_array2_dy" value="number_of_target_bars2 * target_bar_dy + (number_of_target_bars2 - 1) * target_bar_gap" />
+<constant name="target_array2_thickness" value="target_bar_thickness" />
+
+  <!-- target box-->
+<constant name="target_dim_x" value="target_bar_dx" />
+<constant name="target_dim_y" value="target_array2_dy" />
+<constant name="target_thickness" value="2*target_bar_thickness + target_bar_gap" />      <!-- 1.4 mm -->
+
+<!-- Target positions -->
+  <!-- The LYSO layers are indexed from upstream to downstream. -->
+  <!-- target array1-->
+<constant name="target_array1_first_bar_y" value="-(number_of_target_bars1 - 1) * (target_bar_dy + target_bar_gap) / 2" />
+<constant name="target_array1_x" value="0" />
+<constant name="target_array1_y" value="0" />
+<constant name="target_array1_z" value="-(target_bar_thickness + target_bar_gap) / 2" />
+  <!-- target array2-->
+<constant name="target_array2_first_bar_y" value="-(number_of_target_bars2 - 1) * (target_bar_dy + target_bar_gap) / 2" />
+<constant name="target_array2_x" value="0" />
+<constant name="target_array2_y" value="0" />
+<constant name="target_array2_z" value="(target_bar_thickness + target_bar_gap) / 2" />
 
 <!-- 
     Magnet
 --> 
-
-<!-- Magnet is position such that the field center is at -40 cm. -->
+<!-- No magnet in ESA, this is kept for consistency -->
 <constant name="magnet_pos_z" value="-40*cm" />
-
 <!-- Magnet gap dimensions --> 
 <constant name="magnet_gap_dx" value="430*mm"/>
 <constant name="magnet_gap_dy" value="350*mm"/>
@@ -39,32 +70,46 @@
 
 <constant name="trigger_pad_thickness"      value="4.5*mm" />
 <constant name="trigger_pad_bar_thickness"  value="2*mm" />
-<constant name="trigger_pad_bar_gap"        value="0.3*mm" />
+<constant name="trigger_pad_bar_gap"        value="2*mm" />
 <constant name="trigger_pad_dim_x"          value="target_dim_x" />
 <constant name="trigger_pad_dim_y"          value="target_dim_y" />
 <constant name="trigger_bar_dx"             value="30"/>
-<constant name="trigger_bar_dy"             value="3.05"/>   
-<constant name="number_of_bars"             value="24"/>
+<constant name="trigger_bar_dy"             value="3.0"/>   
+<constant name="number_of_bars"             value="12"/>
+
+<constant name="trigger_bar_y_gap"          value="0.15*mm"/>
+<constant name="trigger_layer_y_shift"      value="1.55*mm"/>
 
 <constant name="trigger_pad_offset"    
           value="(target_dim_y - (number_of_bars*trigger_bar_dy + (number_of_bars - 1)*trigger_pad_bar_gap))/2" />
 
-<!-- Trigger pad distance from the target is -2.4262 --> 
+<!-- TS1–TS2 center-to-center separation -->
 <constant name="trig_scint_pad12_separation"
-          value="60"/>
+          value="76.2*mm"/>
 <constant name="trigger_pad1_z"
           value="- trig_scint_pad12_separation - trigger_pad_thickness/2 - clearance" />
 <constant name="trigger_pad2_z"    
           value="-(trigger_pad_thickness/2) - clearance" />
+<!-- TS3 center position relative to target center -->
 <constant name="trigger_pad3_z"      
-          value="target_z - (target_thickness/2) - (trigger_pad_thickness/2) - clearance" />
+          value="-76.2*mm" />
 
 <!-- Parent volume dimensions --> 
 <constant name="trig_scint_area_envelope_x" value="magnet_gap_dx - 5" />
 <constant name="trig_scint_area_envelope_y" value="magnet_gap_dy - 5" />
 <constant name="trig_scint_area_envelope_z" 
           value="-trigger_pad1_z + trigger_pad_thickness + 2*clearance"/>
 
+<!-- light-pipe-specific constants -->
+<constant name="lp_bar_dy"        value="2.0*mm"/>
+<constant name="lp_bar_y_gap"     value="1.15*mm"/>
+<constant name="lp_layer_y_shift" value="1.55*mm"/>
+<constant name="lp_pad_offset"
+          value="(target_dim_y
+                   - (number_of_bars*lp_bar_dy
+                      + (number_of_bars - 1)*lp_bar_y_gap))/2"/>
+
+
 <!--
   Tracker common variables 
 -->
@@ -129,7 +174,7 @@
   either side 
 -->
 <variable name="tagger_envelope_dz" 
-    value="tracker_envelope_clearance*2 + tagger_layer_delta*6" />
+    value="tracker_envelope_clearance*2 + tagger_layer_delta" />
 
 
 <!--
@@ -418,4 +463,4 @@ This value is in mm
 --> 
 <constant name="ecal_envelope_x" value="ecal_side_dx" /> 
 <constant name="ecal_envelope_y" value="ecal_side_dy" /> 
-<constant name="ecal_envelope_z" value="600.0" /> 
+<constant name="ecal_envelope_z" value="600.0" /> 
diff --git a/Detectors/data/ldmx-reduced-v3/detector.gdml b/Detectors/data/ldmx-reduced-v3/detector.gdml
@@ -10,25 +10,25 @@
     &constants;  
 
     <!--
-      Position of the tagger and recoil tracker envelopes with respect to
-      target.  The 9 mm offset was chosen such that the midpoints of the 
-      last (first) layer of the tagger (recoil) tracker are 25 mm apart.
+      ESA layout: two trackers upstream of the target
+      Tracker 1 center:  -240.5 mm
+      Tracker 2 center:  -140.5 mm
+      Spacing between them = 100 mm
     -->
-    <variable name="tagger_pos_z" value="-9*mm - tagger_envelope_dz/2" /> 
-    <variable name="recoil_pos_z" value="9*mm + recoil_envelope_dz/2"/>
+    <variable name="tagger_pos_z" value="-240.5*mm" /> 
+    <variable name="recoil_pos_z" value="-140.5*mm"/>
 
     <!-- Position of the ECal and HCal parent volumes -->
     <constant name="em_calorimeter_pos_z" value="ecal_front_z" />
     <constant name="hadron_calorimeter_pos_z" value="ecal_front_z + hcal_dz/2." />
 
     <!--
-      Trigger scintillator parent volume position relative to the target
-      ???? mm. The end of the parent volume relative to the target
-      is at ?????. This gives a ???? mm clearance between the upstream.
-      There are now two TS modules upstream of the tagger tracker.
+      ESA layout: TS parent volume center
+      Chosen so that TS1 and TS2 centers land at -381.0 mm and -304.8 mm
+      Spacing between them = 76.2 mm
     -->
     <variable name="trig_scint_pos_z" 
-      value="tagger_pos_z-trig_scint_area_envelope_z/2 -tagger_envelope_dz/2- clearance - 200" />
+          value="-344.0255*mm" />
 
     <!-- 
          Define all subdetector positions relative to the target.  
@@ -102,9 +102,9 @@
     <!-- detector version -->
     <auxiliary auxtype="DetectorVersion" auxvalue="1">
       <auxiliary auxtype="DetectorName" auxvalue="ldmx-reduced-v3"/>
-      <auxiliary auxtype="Author" auxvalue="Tamas Vami, Sanjit Masanam"/>
+      <auxiliary auxtype="Author" auxvalue="[placeholder]"/>
       <auxiliary auxtype="Description" 
-                 auxvalue="The reduced geometry for the 2025 vertical slice test"/>
+                 auxvalue="The reduced geometry for ESA run"/>
     </auxiliary>
 
     <!-- define regions -->

diff --git a/Detectors/data/ldmx-reduced-v3/ecal.gdml b/Detectors/data/ldmx-reduced-v3/ecal.gdml
@@ -906,4 +906,4 @@
     </auxiliary> 
   </userinfo>  
 
-</gdml>
+</gdml>
diff --git a/Detectors/data/ldmx-reduced-v3/materials.gdml b/Detectors/data/ldmx-reduced-v3/materials.gdml
@@ -17,7 +17,12 @@
 <element Z="74" formula="W" name="W">
   <atom type="A" unit="g/mol" value="183.842"/>
 </element>           
-
+<element name="Lu" formula="Lu" Z="71">
+  <atom value="174.9668" unit="g/mole"/>
+</element>
+<element name="Y" formula="Y" Z="39">
+  <atom value="88.90584" unit="g/mole"/>
+</element>
 <material name="Air" state="gas">
   <MEE unit="eV" value="85.643664635028"/>
   <D unit="g/cm3" value="0.00119999936860922"/>
@@ -43,3 +48,16 @@
   <D unit="g/cm3" value="9.99999473841014e-09"/>
   <fraction n="1" ref="H"/>
 </material>
+<material name="AcrylicPMMA">
+  <D type="density" value="1.19" unit="g/cm3"/>
+  <composite n="5" ref="C"/>
+  <composite n="8" ref="H"/>
+  <composite n="2" ref="O"/>
+</material>
+<material formula="Lu1.86Y0.2SiO5" name="LYSO" >
+    <D value="7.1" unit="g/cm3" />
+    <fraction n="0.7211" ref="Lu" />
+    <fraction n="0.0394" ref="Y"  />
+    <fraction n="0.0623" ref="Si" />
+    <fraction n="0.1772" ref="O"  />
+</material>
-Original file line number
+Diff line change
@@ Expand Up / @@ -906,4 +906,4 @@ @@
         </auxiliary>
       </userinfo>
-    </gdml>
+    </gdml>