“School of Particles”

Back to Papers Home
Back to Papers of School of Particles

Paper   IPM / Particles / 11881
School of Particles and Accelerator
  Title:   Measurement of the Polarization of W Bosons with Large Transverse Momenta in W+Jets Events at the LHC
1.  Hessamadin Arfaei
2.  Hamed Bakhshiansohi
3.  Seyed Mohsen Etesami
4.  Ali Fahim
5.  Majid Hashemi
6.  Abideh Jafari
7.  Mohsen Khakzad
8.  A Mohammadi
9.  Mojtaba Mohammadi Najafabadi
10.  Saeid Paktinat Mehdiabadi
11.  Batool Safarzadeh
12.  Maryam Zeinali
  Status:   Published
  Journal: Phys. Rev. Lett.
  No.:  021802
  Vol.:  107
  Year:  2011
  Supported by:  IPM
A first measurement of the polarization of W bosons with large transverse momenta in pp collisions is presented. The measurement is based on 36 pb1 of data recorded at sqrt(s) = 7 TeV by the CMS detector at the LHC. The left-handed, righthanded and longitudinal polarization fractions ( fL, fR, f0) of W bosons with transverse momenta larger than 50 GeV are determined using decays to both electrons and muons. The muon final state yields the most precise measurement, ( fL - fR)=0.240  0.036 (stat.)  0.031 (syst.) and f 0 = 0.183  0.087 (stat.)  0.123 (syst.) for negatively charged W bosons, and ( fL - fR)+ = 0.310  0.036 (stat.)  0.017 (syst.) and f+0 = 0.171  0.085 (stat.)  0.099 (syst.) for positively charged W bosons. This establishes, for the first time, that W bosons produced in pp collisions with large transverse momenta are predominantly left-handed, as expected in the standard model

Download TeX format
back to top
Clients Logo
Clients Logo
Clients Logo
Clients Logo
Clients Logo
Clients Logo
Clients Logo
Clients Logo
scroll left or right