CERN Accelerating science

ATLAS Slides
Report number	ATL-LARG-SLIDE-2009-341
Title	A Layer Correlation Technique for Pion Energy Calibration at the 2004 ATLAS Combined Beam Test
Author(s)	Grahn, K-J (KTH Stockholm)
Corporate author(s)	The ATLAS collaboration
Submitted to	IEEE Nuclear Science Symposium And Medical Imaging Conference, Orlando, FL, USA, 25 Oct - 31 Oct 2009
Submitted by	[email protected] on 25 Oct 2009
Subject category	Detectors and Experimental Techniques
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Abstract	A new method for calibrating the hadron response of a segmented calorimeter is developed and applied to beam test data. It is based on a principal component analysis of the calorimeter layer energy depositions, exploiting longitudinal shower development information to improve the measured energy resolution. The calibration corrections were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the ATLAS calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20 and 180 GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by about 20% compared to the response at the electromagnetic scale.