Massive Gluon search in the top pair lepton+jets channel using Dynamical Likelihood Method with 1.9 fb^{1} 
Kunitaka Kondo(Waseda), Taichi Kubo(Tsukuba), Junji Naganoma(Waseda) 
For the CDF Collaboration 
Description  Plot  Link 
Top quark pair invariant mass: Top quark pair invariant mass is reconstructed eventbyevent using DLM without the production matrix element information. 
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Consistency with SM: The best fitted strengh of coupling by changing the mass and width of Massive Gluon with SM expectations by the pseudoexperiments. The results from data are consistent with the SM expectations within 1.7σ for all the explored parameter space. The nontt background fluctuation give the high 3σ from the pseudo experiment. The difference of figures is the width of Massive Gluon. 
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Upper/Lower Limits: The upper/lower limits on the strength of coupling with 95% confidence level as a function of mass of Massive Gluon. The difference of figures is the width of Massive Gluon. The yellow regions are excluded. The limits become worse at the larger width. 
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Likelihood fit example: The examples assuming Γ/M=0.1 and M=800 GeV. The example of the fit (Top left) and 2log[likelihood] (top right). The discrepancy with SM expectation is ~1.7σ (bottom left). The lower/upper limits (bottom right). 

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Top quark transverse momenta: The primary effect of Massive Gluon appears in the top pair invariant mass distribution. The secondary effect will appear in the Pt of the top quarks. The top quark Pt's are reconstructed by the same way as the top pair invariant mass. No significant discrepancy can be seen. 
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Likelihood distribution: Data and MC comparison in log(likehood) distribution as a validation. 
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Transfer function validation: Data and MC comparison in the bottom/light quark and the neutrino resoponse variables by taking the eventbyevent maximum like response. 
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