arXiv subjects

Jaroslav Zalesak

Publications and source records attributed to Jaroslav Zalesak.

3 recordsLinked to original sources

arXiv2012

Calibration Issues for the CALICE 1m3 AHCAL

The CALICE collaboration investigates diferent technology options for highly granular calorimeters for detectors at a future electron-positron collider. One of the devices constructed and tested by this collaboration is a 1m3 prototype of a scintillator-steel sampling calorimeter for hadrons with analogue readout (AHCAL). The light from 7608 small scintillator cells is detected with silicon photomultipliers. The AHCAL has been successfully operated during electron and hadron test-beam measurements at DESY, CERN, and Fermilab since 2005. One of main tasks for the successful data taking is to establish procedures for the equalization of cell responses and calibration of such a large number of channels.

physics.ins-det↗

arXiv2012

Calibration System with Optical Fibers for Calorimeters at Future Linear Collider Experiments

We report on several versions of the calibration and monitoring system dedicated to scintillator tile calorimeters built within the CALICE collaboration and intended for future linear collider experiments. Whereas the first, a 1 m3 analogue hadron calorimeter prototype, was already built and tested in beam, second-technological prototype-is currently being developed. Both prototypes are based on scintillating tiles that are individually read out by new photodetectors, silicon photomultipliers (SiPMs). Since the SiPM response shows a strong dependence on the temperature and bias voltage and the SiPM saturates due to the limited number of pixels, it needs to be monitored. The monitoring system has to have sufficient flexibility to perform several different tasks. The self-calibration property of the SiPMs can be used for the gain monitoring using a low intensity of the LED light. A routine monitoring of all SiPMs during test beam operations is achieved with a fixed-intensity light pulse. The full SiPM response function is cross-checked by varying the light intensity from zero to the saturation level. We concentrate especially on the last aspect - the high dynamic range.

physics.ins-det↗

arXiv2011

Beam test of the QMB6 calibration board and HBU0 prototype

We report about the performance of the HBU0 board and the optical calibration system QMB6 in the DESY test beam. A MIP signal was measured on the HBU0 board, providing a reference to the LED amplitude scan, showing an amount of light delivered to each of 12 SiPMs from 0 to 250 MIP at maximum. An ASIC analogue memory cell performance was analyzed in relation with the SiPM signal strength. We observed a non-uniformity and a pedestal shift in the ASIC readout values in the high gain mode for the higher signals strength.

physics.ins-det↗