t-Quark Electric Charge

INSPIRE   PDGID:
Q007TQ
VALUE DOCUMENT ID TECN  COMMENT
0.64 ±0.02 ±0.08 1
AAD
2013AY
 ATLS ℓ+E̸T+≥4 jets (≥1 b)
• • We do not use the following data for averages, fits, limits, etc. • •
2
ABAZOV
2014D
 D0 ℓ+E̸T+≥4 jets (≥2 b)
3
AALTONEN
2013J
 CDF pp― at 1.96 TeV
4
AALTONEN
2010S
 CDF Repl. by AALTONEN 2013J
5
ABAZOV
2007C
 D0 fraction of |q|=4e/3 pair
1  AAD 2013AY result is based on 2.05 fb−1 of pp data at s = 7 TeV, the result is obtained by reconstructing tt― events in the lepton + jets final state, where b-jet charges are tagged by the jet-charge algorithm. This measurement excludes the charge −4/3 assignment to the top quark at more than 8 standard deviations.
2  ABAZOV 2014D result is based on 5.3 fb−1 of pp― data at s=1.96 TeV. The electric charge of system in tt― candidate events is measured from the charges of the leptons from W decay and in b jets. Under the assumption that the system consists of the sum of the top quark and the charge −4/3 quark b′(-4/3) of the same mass, the top quark fraction is found to be f = 0.88 ±0.13 (stat)±0.11 (syst), or the upper bound for the b′(-4/3) contamination of 1 − f < 0.46 (95% CL).
3  AALTONEN 2013J excludes the charge −4/3 assignment to the top quark at 99% CL, using 5.6 fb−1 of data in pp― collisions at s = 1.96 TeV. Result is obtained by reconstructing tt― events in the lepton + jets final state, where b-jet charges are tagged by the jet-charge algorithm.
4  AALTONEN 2010S excludes the charge −4/3 assignment for the top quark [CHANG 1999] at 95%CL, using 2.7 fb−1 of data in pp― collisions at s = 1.96 TeV. Result is obtained by reconstructing tt― events in the lepton + jets final state, where b-jet charges are tagged by the SLT (soft lepton tag) algorithm.
5  ABAZOV 2007C reports an upper limit ρ< 0.80 (90% CL) on the fraction ρ of exotic quark pairs QQ― with electric charge |q| = 4e/3 in tt― candidate events with high pT lepton, missing ET and ≥4 jets. The result is obtained by measuring the fraction of events in which the quark pair decays into W− + b and W+ + b―, where b and b― jets are discriminated by using the charge and momenta of tracks within the jet cones. The maximum CL at which the model of CHANG 1999 can be excluded is 92%. Based on 370 pb−1 of data at s = 1.96 TeV.
References
ABAZOV 2014D
PR D90 051101 Measurement of the Electric Charge of the Top Quark in tt― Events
AAD 2013AY
JHEP 1311 031 Measurement of the Top Quark Charge in pp Collisions at s = 7 TeV with the ATLAS Detector
AALTONEN 2013J
PR D88 032003 Exclusion of Exotic Top-Like Quarks with -4/3 Electric Charge using Jet-Charge Tagging in Single-Lepton tt― Events at CDF
AALTONEN 2010S
PRL 105 101801 Exclusion of an Exotic Top Quark with -4/3 Electric Charge using Soft Lepton Tagging
ABAZOV 2007C
PRL 98 041801 Experimental Discrimination between Charge 2e/3 Top Quark and Charge 4e/3 Exotic Quark Production Scenarios