Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at √s =7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W→eν and W→μν decays, using data from pp collisions at √s =7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb -1 . Using the decay lepton transverse momentum and the missi...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autor principal: Aad, G.
Formato: JOUR
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_14346044_v72_n5_p1_Aad
Aporte de:
Descripción
Sumario:This paper describes an analysis of the angular distribution of W→eν and W→μν decays, using data from pp collisions at √s =7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb -1 . Using the decay lepton transverse momentum and the missing transverse momentum, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f 0 , f L and f R over two ranges of W transverse momentum (p W T ): 35 < p W T < 50 GeV and p W T > 50 GeV. Good agreement is found with theoretical predictions. For p W T >50 GeV, the values of f 0 and f L -f R , averaged over charge and lepton flavour, are measured to be: f 0 =0. 127±0. 030±0. 108 and f L -f R =0. 252±0. 017±0. 030, where the first uncertainties are statistical, and the second include all systematic effects. © 2012 CERN for the benefit of the ATLAS collaboration.