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Title: Measurement of the W boson helicity in top quark decays at D0

Abstract

We present a measurement of the fraction f{sub +} of right-handed W bosons produced in top quark decays, based on a candidate sample of tt events in the l+jets and dilepton decay channels corresponding to an integrated luminosity of 370 pb{sup -1} collected by the D0 detector at the Fermilab Tevatron pp Collider at {radical}(s)=1.96 TeV. We reconstruct the decay angle {theta}* for each lepton. By comparing the cos{theta}* distribution from the data with that for the expected background and signal for various values of f{sub +} (where we assume that the fraction of longitudinally-polarized W bosons has the standard model value of 0.70), we find f{sub +}=0.056{+-}0.080(stat){+-}0.057(syst) (f{sub +}<0.23 at 95% C.L.), consistent with the standard model prediction of f{sub +}=3.6x10{sup -4}.

Authors:
; ; ; ; ; ; ;  [1]; ; ; ; ; ; ; ; ;  [2]; ; ;  [3]
  1. Joint Institute for Nuclear Research, Dubna (Russian Federation)
  2. University of Oklahoma, Norman, Oklahoma 73019 (United States)
  3. Michigan State University, East Lansing, Michigan 48824 (United States) (and others)
Publication Date:
OSTI Identifier:
21010959
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.031102; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA). D0 Collaboration
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COMPARATIVE EVALUATIONS; DISTRIBUTION; FERMILAB TEVATRON; HELICITY; JET MODEL; LEPTONS; PARTICLE DECAY; STANDARD MODEL; T QUARKS; TEV RANGE; W MINUS BOSONS; W PLUS BOSONS

Citation Formats

Abazov, V. M., Alexeev, G. D., Kalinin, A. M., Kharzheev, Y. M., Malyshev, V. L., Tokmenin, V. V., Vertogradov, L. S., Yatsunenko, Y. A., Abbott, B., Gutierrez, P., Hall, I., Jain, S., Kopal, M., Pompos, A., Severini, H., Skubic, P., Strauss, M., Abolins, M., Benitez, J. A., and Brock, R. Measurement of the W boson helicity in top quark decays at D0. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.031102.
Abazov, V. M., Alexeev, G. D., Kalinin, A. M., Kharzheev, Y. M., Malyshev, V. L., Tokmenin, V. V., Vertogradov, L. S., Yatsunenko, Y. A., Abbott, B., Gutierrez, P., Hall, I., Jain, S., Kopal, M., Pompos, A., Severini, H., Skubic, P., Strauss, M., Abolins, M., Benitez, J. A., & Brock, R. Measurement of the W boson helicity in top quark decays at D0. United States. doi:10.1103/PHYSREVD.75.031102.
Abazov, V. M., Alexeev, G. D., Kalinin, A. M., Kharzheev, Y. M., Malyshev, V. L., Tokmenin, V. V., Vertogradov, L. S., Yatsunenko, Y. A., Abbott, B., Gutierrez, P., Hall, I., Jain, S., Kopal, M., Pompos, A., Severini, H., Skubic, P., Strauss, M., Abolins, M., Benitez, J. A., and Brock, R. Thu . "Measurement of the W boson helicity in top quark decays at D0". United States. doi:10.1103/PHYSREVD.75.031102.
@article{osti_21010959,
title = {Measurement of the W boson helicity in top quark decays at D0},
author = {Abazov, V. M. and Alexeev, G. D. and Kalinin, A. M. and Kharzheev, Y. M. and Malyshev, V. L. and Tokmenin, V. V. and Vertogradov, L. S. and Yatsunenko, Y. A. and Abbott, B. and Gutierrez, P. and Hall, I. and Jain, S. and Kopal, M. and Pompos, A. and Severini, H. and Skubic, P. and Strauss, M. and Abolins, M. and Benitez, J. A. and Brock, R.},
abstractNote = {We present a measurement of the fraction f{sub +} of right-handed W bosons produced in top quark decays, based on a candidate sample of tt events in the l+jets and dilepton decay channels corresponding to an integrated luminosity of 370 pb{sup -1} collected by the D0 detector at the Fermilab Tevatron pp Collider at {radical}(s)=1.96 TeV. We reconstruct the decay angle {theta}* for each lepton. By comparing the cos{theta}* distribution from the data with that for the expected background and signal for various values of f{sub +} (where we assume that the fraction of longitudinally-polarized W bosons has the standard model value of 0.70), we find f{sub +}=0.056{+-}0.080(stat){+-}0.057(syst) (f{sub +}<0.23 at 95% C.L.), consistent with the standard model prediction of f{sub +}=3.6x10{sup -4}.},
doi = {10.1103/PHYSREVD.75.031102},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}