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G. Aad - One of the best experts on this subject based on the ideXlab platform.

  • Direct top-Quark decay width measurement in the $$\mathbf {\varvec{t\bar{t}}}$$tt¯ lepton+jets channel at $$\sqrt{s}=8~\text {TeV}$$s=8TeV with the ATLAS experiment
    The European Physical Journal C, 2018
    Co-Authors: M. Aaboud, B. Abbott, O. Abdinov, B. Abeloos, O. S. Abouzeid, N. L. Abraham, Henrik Abramowicz, G. Aad, Syed Hani Abidi, H. Abreu
    Abstract:

    This paper presents a direct measurement of the decay width of the top Quark using $$t\bar{t}$$tt¯ events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in protonproton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb$$^{-1}$$-1. The decay width of the top Quark is measured using a template fit to distributions of kinematic observables associated with the hadronically and semileptonically decaying top Quarks. The result, $$\Gamma _t = 1.76 \pm 0.33~(\text {stat.})~ ^{+0.79}_{-0.68}~(\text {syst.})~\text {GeV}$$Γt=1.76±0.33(stat.)-0.68+0.79(syst.)GeV for a top-Quark mass of 172.5 GeV, is consistent with the prediction of the Standard Model.

  • Search for pair production of heavy vector-like Quarks decaying into hadronic final states in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
    Phys.Rev.D, 2018
    Co-Authors: M. Aaboud, O. Abdinov, B. Abeloos, O. S. Abouzeid, G. Aad, Syed Hani Abidi, Brad Abbott, Deshan Kavishka Abhayasinghe, Nicola Abraham, Henrik Abramowicz
    Abstract:

    A search is presented for the pair production of heavy vectorlike Quarks, TT¯ or BB¯, that decay into final states with jets and no reconstructed leptons. Jets in the final state are classified using a deep neural network as arising from hadronically decaying W/Z bosons, Higgs bosons, top Quarks, or background. The analysis uses data from the ATLAS experiment corresponding to 36.1 fb-1 of proton-proton collisions with a center-of-mass energy of s=13 TeV delivered by the Large Hadron Collider in 2015 and 2016. No significant deviation from the Standard Model expectation is observed. Results are interpreted assuming the vectorlike Quarks decay into a Standard Model boson and a third-generation-Quark, T→Wb,Ht,Zt or B→Wt,Hb,Zb, for a variety of branching ratios. At 95% confidence level, the observed (expected) lower limit on the vectorlike B-Quark mass for a weak-isospin doublet (B, Y) is 950 (890) GeV, and the lower limits on the masses for the pure decays B→Hb and T→Ht, where these results are strongest, are 1010 (970) GeV and 1010 (1010) GeV, respectively.

  • Search for [Formula: see text] decays in [Formula: see text] collisions at [Formula: see text] = 8 TeV with the ATLAS detector.
    The European physical journal. C Particles and fields, 2015
    Co-Authors: G. Aad, R. Aben, J. Abdallah, B. Abi, B. Abbott, O. Abdinov, O. S. Abouzeid, S. Abdel-khalek, M. Abolins, Henrik Abramowicz
    Abstract:

    A search for a massive [Formula: see text] gauge boson decaying to a top Quark and a bottom Quark is performed with the ATLAS detector in [Formula: see text] collisions at the LHC. The dataset was taken at a centre-of-mass energy of [Formula: see text] and corresponds to [Formula: see text] of integrated luminosity. This analysis is done in the hadronic decay mode of the top Quark, where novel jet substructure techniques are used to identify jets from high-momentum top Quarks. This allows for a search for high-mass [Formula: see text] bosons in the range 1.5-3.0 [Formula: see text]. [Formula: see text]-tagging is used to identify jets originating from [Formula: see text]-Quarks. The data are consistent with Standard Model background-only expectations, and upper limits at 95 % confidence level are set on the [Formula: see text] cross section times branching ratio ranging from [Formula: see text] to [Formula: see text] for left-handed [Formula: see text] bosons, and ranging from [Formula: see text] to [Formula: see text] for [Formula: see text] bosons with purely right-handed couplings. Upper limits at 95 % confidence level are set on the [Formula: see text]-boson coupling to [Formula: see text] as a function of the [Formula: see text] mass using an effective field theory approach, which is independent of details of particular models predicting a [Formula: see text] boson.

  • Measurement of Spin Correlation in Top-Antitop Quark Events and Search for Top SQuark Pair Production in pp Collisions at $\sqrt{s}=8$ TeV Using the ATLAS Detector
    Physical Review Letters, 2015
    Co-Authors: G. Aad, S. Albrand, J. Collot, S. Crépé-renaudin, B. Dechenaux, P.a. Delsart, J. Brown, C. Gabaldon, M.h. Genest, J.y. Hostachy
    Abstract:

    A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The correlation between the top and antitop Quark spins is extracted from dilepton $t\bar{t}$ events by using the difference in azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to $A_{helicity} = 0.38 \pm 0.04$, in agreement with the Standard Model prediction. A search is performed for pair production of top sQuarks with masses close to the top Quark mass decaying to predominantly right-handed top Quarks and a light neutralino, the lightest supersymmetric particle. Top sQuarks with masses between the top Quark mass and 191 GeV are excluded at the 95% confidence level.

  • Search for single b*-Quark production with the ATLAS detector at sqrt(s)=7 TeV
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for an excited bottom-Quark b* in pp collisions at sqrt(s)=7 TeV, using 4.7/fb of data collected by the ATLAS detector at the LHC are presented. In the model studied, a single b*-Quark is produced through a chromomagnetic interaction and subsequently decays to a W boson and a top-Quark. The search is performed in the dilepton and lepton+jets final states, which are combined to set limits on b*-Quark couplings for a range of b*-Quark masses. For a benchmark with unit size chromomagnetic and Standard Model-like electroweak b* couplings, b*-Quarks with masses less than 870 GeV are excluded at the 95% credibility level.

P.a. Delsart - One of the best experts on this subject based on the ideXlab platform.

  • Measurement of Spin Correlation in Top-Antitop Quark Events and Search for Top SQuark Pair Production in pp Collisions at $\sqrt{s}=8$ TeV Using the ATLAS Detector
    Physical Review Letters, 2015
    Co-Authors: G. Aad, S. Albrand, J. Collot, S. Crépé-renaudin, B. Dechenaux, P.a. Delsart, J. Brown, C. Gabaldon, M.h. Genest, J.y. Hostachy
    Abstract:

    A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The correlation between the top and antitop Quark spins is extracted from dilepton $t\bar{t}$ events by using the difference in azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to $A_{helicity} = 0.38 \pm 0.04$, in agreement with the Standard Model prediction. A search is performed for pair production of top sQuarks with masses close to the top Quark mass decaying to predominantly right-handed top Quarks and a light neutralino, the lightest supersymmetric particle. Top sQuarks with masses between the top Quark mass and 191 GeV are excluded at the 95% confidence level.

  • Search for single b*-Quark production with the ATLAS detector at sqrt(s)=7 TeV
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for an excited bottom-Quark b* in pp collisions at sqrt(s)=7 TeV, using 4.7/fb of data collected by the ATLAS detector at the LHC are presented. In the model studied, a single b*-Quark is produced through a chromomagnetic interaction and subsequently decays to a W boson and a top-Quark. The search is performed in the dilepton and lepton+jets final states, which are combined to set limits on b*-Quark couplings for a range of b*-Quark masses. For a benchmark with unit size chromomagnetic and Standard Model-like electroweak b* couplings, b*-Quarks with masses less than 870 GeV are excluded at the 95% credibility level.

  • Search for light top sQuark pair production in final states with leptons and b-jets with the ATLAS detector in sqrt(s) = 7 TeV proton-proton collisions
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for pair production of light top sQuarks are presented, using 4.7 fb^-1 of sqrt(s) = 7 TeV proton-proton collisions collected with the ATLAS detector at the Large Hadron Collider. This search targets top sQuarks with masses similar to, or lighter than, the top Quark mass. Final states containing exclusively one or two leptons (e, mu), large missing transverse momentum, light-jets and b-jets are used to reconstruct the top sQuark pair system. Global mass scale variables are used to separate the signal from a large ttbar background. No excess over the Standard Model expectations is found. The results are interpreted in the framework of the Minimal Supersymmetric Standard Model, assuming the top sQuark decays exclusively to a chargino and a b-Quark. Light top sQuarks with masses between 123-167 GeV are excluded for neutralino masses around 55 GeV.

  • Search for heavy vector-like Quarks coupling to light Quarks in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector
    Physics Letters B, 2012
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, T. Delemontex, P.a. Delsart, J.y. Hostachy
    Abstract:

    This letter presents a search for singly produced vector-like Quarks, Q, coupling to light Quarks, q. The search is sensitive to both charged current (CC) and neutral current (NC) processes, p p --> Q q --> W q q' and p p --> Q q --> Z q q' with a leptonic decay of the vector gauge boson. In 1.04/fb of data taken in 2011 by the ATLAS experiment at a center-of-mass energy sqrt(s) = 7 TeV, no evidence of such heavy vector-like Quarks is observed above the expected Standard Model background. Limits on the heavy vector-like Quark production cross section times branching ratio as a function of mass m_Q are obtained. For a coupling kappa_(qQ) = v/m_Q, where v is the Higgs vacuum expectation value, 95% C.L. lower limits on the mass of a vector-like Quark are set at 900 GeV and 760 GeV from CC and NC processes, respectively.

M. Aaboud - One of the best experts on this subject based on the ideXlab platform.

  • measurement of the top Quark mass in the tt lepton jets channel from s 8 tev atlas data and combination with previous results
    European Physical Journal C, 2019
    Co-Authors: M. Aaboud, A Kupco, S Webb, K Jakobs, M Spousta, M Cobal, T Dreyer, Yufeng Wang, Peilong Wang, S Schmitt
    Abstract:

    The top Quark mass is measured using a template method in the tt¯ → lepton + jets channel (lepton is e or μ) using ATLAS data recorded in 2012 at the LHC. The data were taken at a protonproton centre-of-mass energy of s=8 TeV and correspond to an integrated luminosity of 20.2 fb - 1 . The tt¯ → lepton + jets channel is characterized by the presence of a charged lepton, a neutrino and four jets, two of which originate from bottom Quarks (b). Exploiting a three-dimensional template technique, the top Quark mass is determined together with a global jet energy scale factor and a relative b-to-light-jet energy scale factor. The mass of the top Quark is measured to be mtop=172.08±0.39(stat)±0.82(syst) GeV. A combination with previous ATLAS m top measurements gives mtop=172.69±0.25(stat)±0.41(syst) GeV. © 2019, CERN for the benefit of the ATLAS collaboration.

  • search for pair production of up type vector like Quarks and for four top Quark events in final states with multiple b jets with the atlas detector
    Journal of High Energy Physics, 2018
    Co-Authors: M. Aaboud, A Kupco, S Webb, K Jakobs, M Spousta, M Cobal, T Dreyer, Yufeng Wang, Peilong Wang, S Schmitt
    Abstract:

    A search for pair production of up-type vector-like Quarks (T) with a significant branching ratio into a top Quark and either a Standard Model Higgs boson or a Z boson is presented. The same analys ...

  • Direct top-Quark decay width measurement in the $$\mathbf {\varvec{t\bar{t}}}$$tt¯ lepton+jets channel at $$\sqrt{s}=8~\text {TeV}$$s=8TeV with the ATLAS experiment
    The European Physical Journal C, 2018
    Co-Authors: M. Aaboud, B. Abbott, O. Abdinov, B. Abeloos, O. S. Abouzeid, N. L. Abraham, Henrik Abramowicz, G. Aad, Syed Hani Abidi, H. Abreu
    Abstract:

    This paper presents a direct measurement of the decay width of the top Quark using $$t\bar{t}$$tt¯ events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in protonproton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb$$^{-1}$$-1. The decay width of the top Quark is measured using a template fit to distributions of kinematic observables associated with the hadronically and semileptonically decaying top Quarks. The result, $$\Gamma _t = 1.76 \pm 0.33~(\text {stat.})~ ^{+0.79}_{-0.68}~(\text {syst.})~\text {GeV}$$Γt=1.76±0.33(stat.)-0.68+0.79(syst.)GeV for a top-Quark mass of 172.5 GeV, is consistent with the prediction of the Standard Model.

  • Search for pair production of heavy vector-like Quarks decaying into hadronic final states in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
    Phys.Rev.D, 2018
    Co-Authors: M. Aaboud, O. Abdinov, B. Abeloos, O. S. Abouzeid, G. Aad, Syed Hani Abidi, Brad Abbott, Deshan Kavishka Abhayasinghe, Nicola Abraham, Henrik Abramowicz
    Abstract:

    A search is presented for the pair production of heavy vectorlike Quarks, TT¯ or BB¯, that decay into final states with jets and no reconstructed leptons. Jets in the final state are classified using a deep neural network as arising from hadronically decaying W/Z bosons, Higgs bosons, top Quarks, or background. The analysis uses data from the ATLAS experiment corresponding to 36.1 fb-1 of proton-proton collisions with a center-of-mass energy of s=13 TeV delivered by the Large Hadron Collider in 2015 and 2016. No significant deviation from the Standard Model expectation is observed. Results are interpreted assuming the vectorlike Quarks decay into a Standard Model boson and a third-generation-Quark, T→Wb,Ht,Zt or B→Wt,Hb,Zb, for a variety of branching ratios. At 95% confidence level, the observed (expected) lower limit on the vectorlike B-Quark mass for a weak-isospin doublet (B, Y) is 950 (890) GeV, and the lower limits on the masses for the pure decays B→Hb and T→Ht, where these results are strongest, are 1010 (970) GeV and 1010 (1010) GeV, respectively.

J. Collot - One of the best experts on this subject based on the ideXlab platform.

  • Measurement of Spin Correlation in Top-Antitop Quark Events and Search for Top SQuark Pair Production in pp Collisions at $\sqrt{s}=8$ TeV Using the ATLAS Detector
    Physical Review Letters, 2015
    Co-Authors: G. Aad, S. Albrand, J. Collot, S. Crépé-renaudin, B. Dechenaux, P.a. Delsart, J. Brown, C. Gabaldon, M.h. Genest, J.y. Hostachy
    Abstract:

    A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The correlation between the top and antitop Quark spins is extracted from dilepton $t\bar{t}$ events by using the difference in azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to $A_{helicity} = 0.38 \pm 0.04$, in agreement with the Standard Model prediction. A search is performed for pair production of top sQuarks with masses close to the top Quark mass decaying to predominantly right-handed top Quarks and a light neutralino, the lightest supersymmetric particle. Top sQuarks with masses between the top Quark mass and 191 GeV are excluded at the 95% confidence level.

  • Search for single b*-Quark production with the ATLAS detector at sqrt(s)=7 TeV
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for an excited bottom-Quark b* in pp collisions at sqrt(s)=7 TeV, using 4.7/fb of data collected by the ATLAS detector at the LHC are presented. In the model studied, a single b*-Quark is produced through a chromomagnetic interaction and subsequently decays to a W boson and a top-Quark. The search is performed in the dilepton and lepton+jets final states, which are combined to set limits on b*-Quark couplings for a range of b*-Quark masses. For a benchmark with unit size chromomagnetic and Standard Model-like electroweak b* couplings, b*-Quarks with masses less than 870 GeV are excluded at the 95% credibility level.

  • Search for light top sQuark pair production in final states with leptons and b-jets with the ATLAS detector in sqrt(s) = 7 TeV proton-proton collisions
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for pair production of light top sQuarks are presented, using 4.7 fb^-1 of sqrt(s) = 7 TeV proton-proton collisions collected with the ATLAS detector at the Large Hadron Collider. This search targets top sQuarks with masses similar to, or lighter than, the top Quark mass. Final states containing exclusively one or two leptons (e, mu), large missing transverse momentum, light-jets and b-jets are used to reconstruct the top sQuark pair system. Global mass scale variables are used to separate the signal from a large ttbar background. No excess over the Standard Model expectations is found. The results are interpreted in the framework of the Minimal Supersymmetric Standard Model, assuming the top sQuark decays exclusively to a chargino and a b-Quark. Light top sQuarks with masses between 123-167 GeV are excluded for neutralino masses around 55 GeV.

  • Search for heavy vector-like Quarks coupling to light Quarks in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector
    Physics Letters B, 2012
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, T. Delemontex, P.a. Delsart, J.y. Hostachy
    Abstract:

    This letter presents a search for singly produced vector-like Quarks, Q, coupling to light Quarks, q. The search is sensitive to both charged current (CC) and neutral current (NC) processes, p p --> Q q --> W q q' and p p --> Q q --> Z q q' with a leptonic decay of the vector gauge boson. In 1.04/fb of data taken in 2011 by the ATLAS experiment at a center-of-mass energy sqrt(s) = 7 TeV, no evidence of such heavy vector-like Quarks is observed above the expected Standard Model background. Limits on the heavy vector-like Quark production cross section times branching ratio as a function of mass m_Q are obtained. For a coupling kappa_(qQ) = v/m_Q, where v is the Higgs vacuum expectation value, 95% C.L. lower limits on the mass of a vector-like Quark are set at 900 GeV and 760 GeV from CC and NC processes, respectively.

S. Albrand - One of the best experts on this subject based on the ideXlab platform.

  • Measurement of Spin Correlation in Top-Antitop Quark Events and Search for Top SQuark Pair Production in pp Collisions at $\sqrt{s}=8$ TeV Using the ATLAS Detector
    Physical Review Letters, 2015
    Co-Authors: G. Aad, S. Albrand, J. Collot, S. Crépé-renaudin, B. Dechenaux, P.a. Delsart, J. Brown, C. Gabaldon, M.h. Genest, J.y. Hostachy
    Abstract:

    A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The correlation between the top and antitop Quark spins is extracted from dilepton $t\bar{t}$ events by using the difference in azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to $A_{helicity} = 0.38 \pm 0.04$, in agreement with the Standard Model prediction. A search is performed for pair production of top sQuarks with masses close to the top Quark mass decaying to predominantly right-handed top Quarks and a light neutralino, the lightest supersymmetric particle. Top sQuarks with masses between the top Quark mass and 191 GeV are excluded at the 95% confidence level.

  • Search for single b*-Quark production with the ATLAS detector at sqrt(s)=7 TeV
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for an excited bottom-Quark b* in pp collisions at sqrt(s)=7 TeV, using 4.7/fb of data collected by the ATLAS detector at the LHC are presented. In the model studied, a single b*-Quark is produced through a chromomagnetic interaction and subsequently decays to a W boson and a top-Quark. The search is performed in the dilepton and lepton+jets final states, which are combined to set limits on b*-Quark couplings for a range of b*-Quark masses. For a benchmark with unit size chromomagnetic and Standard Model-like electroweak b* couplings, b*-Quarks with masses less than 870 GeV are excluded at the 95% credibility level.

  • Search for light top sQuark pair production in final states with leptons and b-jets with the ATLAS detector in sqrt(s) = 7 TeV proton-proton collisions
    Physics Letters B, 2013
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, B. Dechenaux, T. Delemontex, P.a. Delsart
    Abstract:

    The results of a search for pair production of light top sQuarks are presented, using 4.7 fb^-1 of sqrt(s) = 7 TeV proton-proton collisions collected with the ATLAS detector at the Large Hadron Collider. This search targets top sQuarks with masses similar to, or lighter than, the top Quark mass. Final states containing exclusively one or two leptons (e, mu), large missing transverse momentum, light-jets and b-jets are used to reconstruct the top sQuark pair system. Global mass scale variables are used to separate the signal from a large ttbar background. No excess over the Standard Model expectations is found. The results are interpreted in the framework of the Minimal Supersymmetric Standard Model, assuming the top sQuark decays exclusively to a chargino and a b-Quark. Light top sQuarks with masses between 123-167 GeV are excluded for neutralino masses around 55 GeV.

  • Search for heavy vector-like Quarks coupling to light Quarks in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector
    Physics Letters B, 2012
    Co-Authors: G. Aad, S. Albrand, M.l. Andrieux, Q. Buat, B. Clement, J. Collot, S. Crépé-renaudin, T. Delemontex, P.a. Delsart, J.y. Hostachy
    Abstract:

    This letter presents a search for singly produced vector-like Quarks, Q, coupling to light Quarks, q. The search is sensitive to both charged current (CC) and neutral current (NC) processes, p p --> Q q --> W q q' and p p --> Q q --> Z q q' with a leptonic decay of the vector gauge boson. In 1.04/fb of data taken in 2011 by the ATLAS experiment at a center-of-mass energy sqrt(s) = 7 TeV, no evidence of such heavy vector-like Quarks is observed above the expected Standard Model background. Limits on the heavy vector-like Quark production cross section times branching ratio as a function of mass m_Q are obtained. For a coupling kappa_(qQ) = v/m_Q, where v is the Higgs vacuum expectation value, 95% C.L. lower limits on the mass of a vector-like Quark are set at 900 GeV and 760 GeV from CC and NC processes, respectively.