Münster 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

T: Fachverband Teilchenphysik

T 63: Experimentelle Methoden 2 (Flavour-,Photon,Elektronidentifikation)

T 63.5: Vortrag

Dienstag, 28. März 2017, 17:50–18:05, JUR 253

Measurement of the Photon Identification Efficiency in the ATLAS Experiment — •Früd Braren — DESY, Hamburg, Deutschland

The detection and identification of photons in high-energy collisions is important for the physics program of the ATLAS experiment at the Large Hadron Collider. Photons produced in collisions in the ATLAS detector are relevant as a probe of QCD and the Standard Model processes in general, as well as the decay of the Higgs boson to a pair of photons. Also signatures of physics beyond the Standard Model may include photons. For measurements and searches involving photons it is vital to know the efficiency with which photons are being identified as such with high precision.

The identification of photons is based on the shape of the electromagnetic shower in the calorimeter and its efficiency needs to be measured using collision data. One of the three currently employed methods for measuring the photon identification efficiency is based on electrons from Z-boson decays using a Tag-and-Probe method. The electron showers, which are subsequently transformed into photon-like objects using shower-shape information from electron- and photon Monte-Carlo samples, can be used to measure the photon identification efficiency in the transverse-momentum range from about 25 GeV to about 120 GeV. This contribution presents the method and results of this measurement, using data corresponding to an integrated luminosity of 36.5 fb⁻¹, collected at a center-of-mass energy of √s=13 TeV.