23-28 June 2014
Amsterdam
Europe/Zurich timezone

ImPACT: A Monte Carlo Template based analysis for Air-Cherenkov Arrays

23 Jun 2014, 18:10
15m
Room 2 (Tuschinski Theatre)

Room 2

Tuschinski Theatre

Presentation Gamma-Ray Astrophysics Gamma-Ray Astrophysics

Speaker

Dr Robert Parsons (Max-Planck-Institut für Kernphysik)

Description

We present a high-performance event reconstruction algorithm: an Image Pixel-wise fit for Atmospheric Cherenkov Telescopes (ImPACT). This gamma-ray event reconstruction algorithm is based around the comparison of camera pixel amplitudes to an expected image template, performing a maximum likelihood fit to find the best-fit shower parameters. Related reconstruction algorithms have already been shown to provide significant improvements over traditional reconstruction techniques for both current and previous generation experiments. We demonstrate a significant improvement to the template generation step of the procedure, by the use of a full Monte Carlo air shower simulation in combination with a ray-tracing optics simulation to more accurately model the expected camera images. This reconstruction step is combined with an MVA-based background rejection. Application of the ImPACT analysis to both simulated and measured (from a strong VHE source) gamma-ray data from the H.E.S.S. array demonstrates an improvement in sensitivity of more than a factor two in observation time over traditional image moments-fitting methods, with comparable performance to previous likelihood fitting analyses. ImPACT is a particularly promising approach for future large arrays such as the Cherenkov Telescope Array (CTA) due to its improved high-energy performance and suitability for arrays of mixed telescope types.

Primary author

Dr Robert Parsons (Max-Planck-Institut für Kernphysik)

Co-author

Jim Hinton (University of Leicester)

Presentation Materials