Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HK: Fachverband Physik der Hadronen und Kerne
HK 7: Schwerionenkollisionen und QCD Phasen
HK 7.7: Vortrag
Montag, 19. März 2012, 15:45–16:00, P 5
Measurement of B meson production in pp collisions at √s = 7 TeV via displaced electrons in ALICE — •Markus Heide — WWU Münster
The measurement of the production cross-section of B mesons in pp collisions in ALICE is important in two respects. First it allows to test perturbative quantum chromodynamics calculations. Secondly it provides an essential reference for studies in heavy-ion collisions at high energies, in which a hot and dense medium, the quark-gluon plasma (QGP), is created. When passing through this medium, quarks lose energy via the strong interaction. Since the amount of energy loss depends significantly on the quark mass, beauty as the heaviest observable flavour is of particular interest for the exploration of QGP properties.
A promising method for obtaining the B meson yield is the analysis of electrons from its semileptonic decay channels, whose methods and results will be presented in this talk. First, the electron identification using ALICE’s Time Projection Chamber (TPC) and Time Of Flight (TOF) detector will be outlined. Then it will be explained how we make use of the B mesons’ larger decay length (∼ 500 µm) in comparison to D mesons and other background sources by selecting electrons with a large impact parameter. The method for estimation of the remaining background electrons in the selected sample will be presented, which is based on calculations using ALICE measured pt spectra of π0 and D mesons. As a result, the B meson spectrum measured in pp collisions at √s = 7 TeV in 2010 will be shown.