Implementation of BeamCal in Mokka Alexandra Popescu, Aura Rosca West University of Timisoara FCAL Collaboration Meeting 6-7 May, Krakow, Poland

Overview BeamCal: functionality and structure Detector construction Sensitive detectors Summary

BeamCal Compact EM calorimeter with a sandwich structure: 30 layers of 1X 0 : 3.5 mm absorber and 0.3 mm sensor Angular coverage: ~5-45 mrad Situated at 3450 mm from the IP Purposes: Provide electron and photon identification down to polar angles of a few mrad Protect the inner part of the detector by reducing backscattering from inner parts Assisting beam diagnostics

Mokka implementation Create a local copy of the central database Construct the geometry of the detector Define the sensitive detectors

Geometry construction Drivers: C++ code Databases: MySQL database Sub-detectors: a combination of drivers and databases

Drivers A class which inherits from VSubDetectorDrivers class class BeamCal00: public VSubDetectorDriver The actual construction of the geometry is made by the ContextualConstruct invoked by the geometry manager G4bool ContextualConstruct(const CGAGeometryEnvironment &env, G4LogicalVolume *worldLog); To be available the driver has to be created using the INSTANTIATE macro available in “CGADefs.h” #include "CGADefs.h" INSTANTIATE(BeamCal00)

Geometry data model “models03” database is composed of several tables: detector_concept ingredients model model_parameters parameters scripts setup setup_parameters sharing sub_detector tmp_databases

Geometry data model model name description detector_concept model_status sub_detector id name db driver description ingredients id model sub_detector build_order sharing driver parameter driver_default_value

Database Create a database, using a MySQL script, with the relevant geometry parameters for the detector CREATE DATABASE `beamcalX01_14`; USE beamcalX01_14; DROP TABLE IF EXISTS `beamcal`; CREATE TABLE `beamcal`( `Rinner` double default NULL, `Router` double default NULL, `sPhi` double default NULL, `dPhi` double default NULL, `nWafers` double default NULL, `BPmaxR` double default NULL ); INSERT INTO `beamcal` (Rinner, Router, sPhi, dPhi, nWafers, BPmaxR) VALUES (20., 150., 200., 320., 8., 67.);

10 Connect the driver and the database to form a sub-detector: Geometry construction sub_detector id name db driver description name: BeamCal driver: BeamCal00 database: beamcalX01 Create a detector model that uses this sub-detector: ingredients id model sub_detector build_order model: LDC01_05Sc sub_detector: BeamCal Make the relevant geometry parameters known to the driver: sharing driver parameter driver_default_value driver: BeamCal00 parameter: ILC_Main_Crossing_Angle (default value is 14 mrad) model name description detector_concept model_status

Graphite (100 mm) Air gapDiamond KaptonGold Tungsten Pair monitor BeamCal Geometry

Backward region BeamCal Geometry Segmentation: 17 ring (r) 8 sectors (phi) 140 cells/sector ~ 8mm

Sensitive detector Hit class(es) - CalHit (the generic hit class for calorimeters) - TRKHit (implements a simple hit for the tracking devices) Hit collection Sensitive detector class -has to inherit from the abstract class VSensitiveDetector Register the sensitive detector object using the RegsiterSensitiveDetector() method

Hits Forward regionBackward region

Simulation studies R M =11.8 ±0.4 mm

Summary Implemented in Mokka a realistic description of BeamCal’s geometry Moliere Radius = 11.8 mm (preliminary result) LC TOOLS note in progress