From c8a2698298cb3be0ee27f5b184c315d3deb8f169 Mon Sep 17 00:00:00 2001
From: Christopher Dilks <dilks@jlab.org>
Date: Tue, 10 Aug 2021 23:40:33 +0000
Subject: [PATCH] fix drich segmentation
---
compact/drich.xml | 31 ++++++++++++++++++++++---------
src/DRich_geo.cpp | 6 +++++-
2 files changed, 27 insertions(+), 10 deletions(-)
diff --git a/compact/drich.xml b/compact/drich.xml
index 6a700900..a7051d23 100644
--- a/compact/drich.xml
+++ b/compact/drich.xml
@@ -23,6 +23,9 @@
<constant name="DRICH_rmax2" value="200*cm"/> <!-- cylinder radius; 20 cm gap between dRICh and HCalBarrel -->
<!-- additional parameters -->
<constant name="DRICH_aerogel_thickness" value="4.0*cm"/> <!-- aerogel thickness -->
+ <constant name="DRICH_sensor_size" value="48.0*mm"/> <!-- sensor side length -->
+ <constant name="DRICH_sensor_thickness" value="35.0*mm"/> <!-- sensor thickness -->
+ <constant name="DRICH_num_px" value="16"/> <!-- number of pixels along one side of the sensor -->
</define>
<detectors>
@@ -127,8 +130,8 @@
material="Silicon"
surface="SensorSurface_DRICH"
vis="DRICH_sensor_vis"
- side="48*mm"
- thickness="35*mm"
+ side="DRICH_sensor_size"
+ thickness="DRICH_sensor_thickness"
gap="0.5*(52-48)*mm + 2*mm"
/>
<!-- sensors will be tiled on this sphere
@@ -165,15 +168,25 @@
<readouts>
<readout name="DRICHHits">
- <segmentation type="CartesianGridXY" grid_size_x="3*mm" grid_size_y="3*mm"/>
+ <!-- segmentation: square matrix of pixels
+ - note: for `grid_size`, divide sensor size by 1 less than the
+ number of pixels, to account for fenceposting
+ -->
+ <segmentation
+ type="CartesianGridXY"
+ grid_size_x="DRICH_sensor_size/(DRICH_num_px-1)"
+ grid_size_y="DRICH_sensor_size/(DRICH_num_px-1)"
+ offset_x="-DRICH_sensor_size/2.0"
+ offset_y="-DRICH_sensor_size/2.0"
+ />
<!-- cellID: 64bits
- - bits 1-8: dRICh ID
- - bits 9-16: sector number
- - bits 17-32: photosensor number
- - bits 33-48: x pixel (signed)
- - bits 49-64: y pixel (signed)
+ - offset 0, length 8: dRICh ID
+ - offset 8, length 3: sector number
+ - offset 11, length 12: photosensor number
+ - offset 23, length 16: x pixel
+ - offset 39, length 16: y pixel
-->
- <id>system:8,sector:8,module:16,x:32:-16,y:-16</id>
+ <id>system:8,sector:3,module:12,x:23:16,y:16</id>
</readout>
</readouts>
diff --git a/src/DRich_geo.cpp b/src/DRich_geo.cpp
index 5d9ebd83..645d2965 100644
--- a/src/DRich_geo.cpp
+++ b/src/DRich_geo.cpp
@@ -296,7 +296,7 @@ static Ref_t createDetector(Detector& desc, xml::Handle_t handle, SensitiveDetec
*/
// initialize module number for this sector
- int imod=1;
+ int imod=0;
// thetaGen loop: iterate less than "0.5 circumference / sensor size" times
double nTheta = M_PI*sensorSphRadius / (sensorSide+sensorGap);
@@ -354,8 +354,12 @@ static Ref_t createDetector(Detector& desc, xml::Handle_t handle, SensitiveDetec
* RotationZ(thetaGen) // rotate about `yGen`
* Translation3D(sensorSphRadius, 0., 0.) // push radially to spherical surface
* RotationY(M_PI/2) // rotate sensor to be compatible with generator coords
+ * RotationZ(-M_PI/2) // correction for readout segmentation mapping
);
+ // generate LUT for module number -> sensor position, for readout mapping tests
+ //if(isec==0) printf("%d %f %f\n",imod,sensorPV.position().x(),sensorPV.position().y());
+
// properties
sensorPV.addPhysVolID("sector", isec).addPhysVolID("module", imod);
DetElement sensorDE(det, Form("sensor_de%d_%d", isec, imod), 10000*isec+imod);
--
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