Analysis of Flash ADC Data With VERITAS - AstrophysicsReport as inadecuate

Analysis of Flash ADC Data With VERITAS - Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: VERITAS employs a 12m segmented mirror and pixellated photomultiplier tubecamera to detect the brief pulse of Cherenkov radiation produced by theextensive air shower initiated by a cosmic high-energy gamma ray. The VERITASdata acquisition system consists of a 500 Mega-Sample-Per-Second custom-builtflash ADC system, which samples the Cherenkov light pulse every 2 nanoseconds.The integrated charge in each flash ADC channel is proportional to the amountof Cherenkov light incident on the corresponding photomultiplier tube. Accuratereconstruction of the integrated charge is required for accurate energyestimation and spectral reconstruction. A reliable calculation of theintegrated charge at low intensities can lead to a reduction in the energythreshold of the system, and an increase in sensitivity. This paperinvestigates and compares several approaches for evaluating the integratedcharge. The Cherenkov pulse timing information in the flash ADC readout has thepotential to assist in background rejection techniques. Various methods forextracting the timing information are investigated and excellent timingresolution is achieved.

Author: P. Cogan, for the VERITAS Collaboration



Related documents