Description of the simulation of a LED-based calibration system for the LYSO calorimeter.

Introduction

A preliminary version of calibration mode has been implemented. The idea is to investigate the feasibility of utilizing a LED system to provide a controlled signal for the calibration of the LYSO calorimeter and how, however, the presence of light guides can influence the resolution of the measured energy.

Several upgrades could be implemented in the future.

Construction and Primary Generator details

In the current version, the light guides, defined in the method MyDetectorConstruction::ConstructLightGuide(), feature 4 holes to allow the insertion of LEDs. During calibration mode, it is essential to remember to insert the light guides using the command:

/MC_LYSO/my_construction/isLightGuide true

Once the 8 spots are created, the LED simulation takes place within the MyPrimaryGenerator class. It is possible to set the isotropic emission of a blue optical photon (for emission according to Lambert's cosine law, the use of G4GeneralParticleSource instead of G4ParticleGun would be necessary) from inside one of the holes in the light guides.

Firstly, it is necessary to enable the calibration mode:

/MC_LYSO/my_gun/calibration/enable true

Following this, you should choose in which light guide and in which hole to turn on the LED:

/MC_LYSO/my_gun/calibration/FrontOrBack ["F"ront or "B"ack]

/MC_LYSO/my_gun/calibration/switchOnLED ["u"p or "d"own or "r"ight or "l"eft]

Finally, the run can be initiated through /run/beamOn .

An example of the output can be found in Calibration mode: output example, in the related page.