A study on the in situ calibration of the absolute energy of hadron calorimeters

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 1998-09, Vol.414 (2), p.156-169
• Main Author: Plothow-Besch, H.
• Format: Article
• Language: English
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(98)00584-1

A study on the in situ calibration of the absolute energy scale of hadron calorimeters is presented. The basic idea is to use a physics process, namely Drell–Yan production of tau pairs with the subsequent decay of the tau into a single hadron and a tau-neutrino. The energy of the two charged, isolated hadrons with opposite sign can be measured in the calorimeters. Together with the momentum measurement from tracking detectors the ratio E/ p can then be used to get the absolute energy calibration. The process of Drell–Yan production of tau pairs is very abundant at LHC energies, and at a promising level at the TEVATRON energy in view of the future improved luminosity. The enormous rate from background processes mainly coming from QCD jet production can be handled to a negligible level by using appropriate kinematical cuts. At LHC energies the cut variables described could also serve to separate other physics channels from the background such as the Standard Model H 0→τ +τ − or the supersymmetric A 0→τ +τ −.