From 25c340623ab69f92b0615720b2fe1d591129d50a Mon Sep 17 00:00:00 2001
From: Sam Zhou <zwl20000331@gmail.com>
Date: Sun, 24 Nov 2024 21:07:38 -0800
Subject: [PATCH] Modified the LYSO target design

---
 .../data/ldmx-lyso-r1-v14-8gev/constants.gdml | 55 +++++++++--
 .../data/ldmx-lyso-r1-v14-8gev/materials.gdml |  9 +-
 .../data/ldmx-lyso-r1-v14-8gev/target.gdml    | 98 ++++++++++++-------
 3 files changed, 118 insertions(+), 44 deletions(-)

diff --git a/Detectors/data/ldmx-lyso-r1-v14-8gev/constants.gdml b/Detectors/data/ldmx-lyso-r1-v14-8gev/constants.gdml
index 4de8dbba2..2f2a917dc 100644
--- a/Detectors/data/ldmx-lyso-r1-v14-8gev/constants.gdml
+++ b/Detectors/data/ldmx-lyso-r1-v14-8gev/constants.gdml
@@ -11,13 +11,48 @@
 <!-- 
     Target
 --> 
-<!-- position -->
-<constant name="target_z" value="0.0*mm" />
-<!-- LYSO X0 = 1.10 cm.  Target thickeness = .1X0 -->
-<constant name="target_thickness" value="1.1*mm"/>
+
 <!-- 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="40" />
+<constant name="target_bar_dy" value="3.0" />
+<constant name="target_bar_thickness" value="0.6" />
+<constant name="target_bar_gap" value="0.14" />
+
+  <!-- target array1-->
+<constant name="number_of_target_bars1" value="32" />
+<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="33" />
+<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" />
+
+<!-- Target positions -->
+
+  <!-- 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" />
+
+  <!-- target box-->
+<constant name="target_z" value="0.0*mm" />
 
 <!-- 
     Magnet
@@ -37,6 +72,7 @@
 
 <!-- Trigger scintillator positions -->
 
+<constant name="trigger_gap_with_target"    value="0.93*mm" />
 <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" />
@@ -57,7 +93,7 @@
 <constant name="trigger_pad2_z"    
           value="-(trigger_pad_thickness/2) - clearance" />
 <constant name="trigger_pad3_z"      
-          value="target_z - (target_thickness/2) - (trigger_pad_thickness/2) - clearance" />
+          value="target_z - (target_thickness/2) - (trigger_pad_thickness/2) - trigger_gap_with_target - clearance" />
 
 <!-- Parent volume dimensions --> 
 <constant name="trig_scint_area_envelope_x" value="magnet_gap_dx - 5" />
@@ -65,6 +101,11 @@
 <constant name="trig_scint_area_envelope_z" 
           value="-trigger_pad1_z + trigger_pad_thickness + 2*clearance"/>
 
+    <!-- target_area_box-->
+<constant name="target_area_envelope_x" value="target_array2_dx" />
+<constant name="target_area_envelope_y" value="target_array2_dy" />
+<constant name="target_area_envelope_z" value="2 * (target_thickness/2 + trigger_gap_with_target + trigger_pad_thickness)" />
+
 <!--
   Tracker common variables 
 -->
diff --git a/Detectors/data/ldmx-lyso-r1-v14-8gev/materials.gdml b/Detectors/data/ldmx-lyso-r1-v14-8gev/materials.gdml
index 2403d69f1..fe05e803a 100644
--- a/Detectors/data/ldmx-lyso-r1-v14-8gev/materials.gdml
+++ b/Detectors/data/ldmx-lyso-r1-v14-8gev/materials.gdml
@@ -16,7 +16,14 @@
 </element>
 <element Z="74" formula="W" name="W">
   <atom type="A" unit="g/mol" value="183.842"/>
-</element>           
+</element> 
+<element Z="71" formula="Lu" name="Lu">
+  <atom type="A" unit="g/mol" value="174.967"/>
+</element>
+<element Z="39" formula="Y" name="Y">
+  <atom type="A" unit="g/mol" value="88.90585"/>
+</element>
+
 
 <material name="Air" state="gas">
   <MEE unit="eV" value="85.643664635028"/>
diff --git a/Detectors/data/ldmx-lyso-r1-v14-8gev/target.gdml b/Detectors/data/ldmx-lyso-r1-v14-8gev/target.gdml
index 70833fa2b..d60b4d6b6 100644
--- a/Detectors/data/ldmx-lyso-r1-v14-8gev/target.gdml
+++ b/Detectors/data/ldmx-lyso-r1-v14-8gev/target.gdml
@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <!DOCTYPE gdml [
 <!ENTITY constants SYSTEM "constants.gdml">
+<!ENTITY materials SYSTEM "materials.gdml">
 ]>
 <gdml xmlns:gdml="http://cern.ch/2001/Schemas/GDML" 
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
@@ -8,42 +9,38 @@
 
   <define>
 
-    &constants;   
-    
-    <variable name="x" value="1"/>
+    &constants; 
 
-    <!-- Parent volume dimensions --> 
-    <constant name="target_area_envelope_x" value="magnet_gap_dx - 5" />
-    <constant name="target_area_envelope_y" value="magnet_gap_dy - 5" />
-    <constant name="target_area_envelope_z" value="2*(target_thickness/2 + 2*clearance + trigger_pad_thickness)" />
+    <!--loop variables-->
+    <variable name="x" value="1" />
 
   </define>
 
   <solids>
+    <!-- LYSO target -->
+    <box lunit="mm" name="target_bar" x="target_bar_dx" y="target_bar_dy" z="target_bar_thickness"/>
+    <box lunit="mm" name="target_array1" x="target_array1_dx" y="target_array1_dy" z="target_array1_thickness"/>
+    <box lunit="mm" name="target_array2" x="target_array2_dx" y="target_array2_dy" z="target_array2_thickness"/>
+    <box lunit="mm" name="target_box" x="target_dim_x" y="target_dim_y" z="target_thickness"/>
 
-    <box lunit="mm" name="target_area_box" x="target_area_envelope_x" y="target_area_envelope_y" z="target_area_envelope_z" />
-    <box lunit="mm" name="target_box" x="target_dim_x" y="target_dim_y" z="target_thickness"/> 
+    <!-- Trigger Scintillator -->
     <box lunit="mm" name="trigger_bar_box" x="trigger_bar_dx" y="trigger_bar_dy" z="trigger_pad_bar_thickness" /> 
 
+    <box lunit="mm" name="target_area_box" x="target_area_envelope_x" y="target_area_envelope_y" z="target_area_envelope_z" />
+
 
   </solids>
 
   <materials>
 
-      <material name="Vacuum" state="gas">
+    &materials;
+
+    <material name="Vacuum" state="gas">
       <MEE unit="eV" value="19.2"/>
       <D unit="g/cm3" value="9.99999473841014e-09"/>
       <fraction n="1" ref="H"/>
     </material>
-    
-    <!-- Target --> 
-    <material name="Tungsten" state="solid">
-      <MEE unit="eV" value="727"/>
-      <D unit="g/cm3" value="19.2999898451316"/>
-      <fraction n="1" ref="W"/>
-    </material>
 
-    
     <!-- Scintillator -->
     <material name="Polyvinyltoluene">
       <D type="density" value="1.023" unit="g/cm3"/>
@@ -53,23 +50,56 @@
     
     <!-- LYSO target -->
     <material formula="L1.86Y0.14Si05" name="LYSO" >
-		<D value="7.4" unit="g/cm3"   />
-		<fraction n="0.7297" ref="Lu" />
-		<fraction n="0.0279" ref="Y"  />
-		<fraction n="0.0630" ref="Si" />
-		<fraction n="0.1794" ref="O"  />
+		  <D value="7.4" unit="g/cm3"   />
+		  <fraction n="0.7297" ref="Lu" />
+		  <fraction n="0.0279" ref="Y"  />
+		  <fraction n="0.0630" ref="Si" />
+		  <fraction n="0.1794" ref="O"  />
     </material>
 
-
   </materials>
 
   <structure>
-
-    <volume name="target">
+    <!-- LYSO target -->
+    <volume name="lvTargetBar">
       <materialref ref="LYSO"/>
-      <solidref ref="target_box"/>
-      <auxiliary auxtype="VisAttributes" auxvalue="TargetVis"/>
-      <auxiliary auxtype="DetElem" auxvalue="Target"/>
+      <solidref ref="target_bar"/>
+    </volume>
+    <volume name="lvTargetArray1">
+      <materialref ref="Vacuum"/>
+      <solidref ref="target_array1"/>
+      <loop for="x" from="1" to="number_of_target_bars1" step="1">
+        <physvol>
+          <volumeref ref="lvTargetBar"/>
+          <position name="posTargetBar1" unit="mm" x="0" y="target_array1_first_bar_y + (x-1) * (target_bar_dy + target_bar_gap)" z="0"/>
+          <rotation name="rotTargetBar1" unit="deg" x="0" y="0" z="0"/>
+        </physvol>
+      </loop>     
+    </volume>
+    <volume name="lvTargetArray2">
+      <materialref ref="Vacuum"/>
+      <solidref ref="target_array2"/>
+      <loop for="x" from="1" to="number_of_target_bars2" step="1">
+        <physvol>
+          <volumeref ref="lvTargetBar"/>
+          <position name="posTargetBar2" unit="mm" x="0" y="target_array2_first_bar_y + (x-1) * (target_bar_dy + target_bar_gap)" z="0"/>
+          <rotation name="rotTargetBar2" unit="deg" x="0" y="0" z="0"/>
+        </physvol> 
+      </loop>  
+    </volume>
+    <volume name="lvTarget">
+      <materialref ref="Vacuum"/>
+      <solidref ref="target_box"/>   
+      <physvol name="lvTargetArray1_phys">
+        <volumeref ref="lvTargetArray1"/>
+        <position name="posTarget1" unit="mm" x="target_array1_x" y="target_array1_y" z="target_array1_z"/>
+        <rotation name="rotTarget1" unit="deg" x="0" y="0" z="0"/>
+      </physvol> 
+      <physvol name="lvTargetArray2_phys">
+        <volumeref ref="lvTargetArray2"/>
+        <position name="posTarget2" unit="mm" x="target_array2_x" y="target_array2_y" z="target_array2_z"/>
+        <rotation name="rotTarget2" unit="deg" x="0" y="0" z="0"/>
+      </physvol> 
     </volume>
 
     <volume name="trigger_pad3_bar_volume">
@@ -83,7 +113,7 @@
       <materialref ref="Vacuum"/>
       <solidref ref="target_area_box" />
 
-      <loop for="x" to="number_of_bars" step="1">
+      <loop for="x" from="1" to="number_of_bars" step="1">
         <physvol copynumber="2*x-2">
           <volumeref ref="trigger_pad3_bar_volume" />
           <position name="trigger_pad3_bar_layer1_pos" unit="mm" x="0" 
@@ -100,16 +130,12 @@
         </physvol>
       </loop>
 
-      <physvol copynumber="3">
-        <volumeref ref="target"/>
+      <physvol name="lvTarget_phys">
+        <volumeref ref="lvTarget"/>
         <positionref ref="center"/>
         <rotationref ref="identity"/>
       </physvol>
 
-      <auxiliary auxtype="Region" auxvalue="target" />
-      <!-- <auxiliary auxtype="VisAttributes" auxvalue="InvisibleShowDau"/> -->
-      <auxiliary auxtype="DetElem" auxvalue="target"/>
-
     </volume>
 
   </structure>