Limits on the top-quark chromomagnetic dipole moment from angular distributions in events at with the CMS detector.


A search for new physics in the form of a top quark chromomagnetic anomalous coupling is performed in the differential cross section measured as a function of the difference in azimuthal angle of the two charged leptons, , in the dilepton decay mode. The measured value of is and no sign of new physics is observed. Limits on the real part of the chromomagnetic dipole moment are determined at 95% Confidence Level to be .

Public Document

The document CMS-PAS-TOP-14-005 published on the CERN document server can be found here.


Figures Caption
deltaphi_SM_v2.png Prediction for the distribution of the standard model contribution at the LHC for a centre-of-mass energy of TeV. The prediction, referred to in the text as NLOW, is calculated to next-to-leading-order and includes electroweak corrections.
deltaphi_BSM_v2.png Prediction for the distribution from new physics contributions (NP) at the LHC for a centre-of-mass energy of TeV.
deltaphi_data_SM_v2.png The differential cross section as observed in data, and as predicted by the standard model (NLOW). The solid black line corresponds to the nominal calculation, while the dashed red and dash-dotted blue lines correspond to up and down variations of the renormalization and factorization scales, respectively.
deltaphi_data_Fit_statPlusSyst_v2.png The differential cross section as observed in data and predicted by the standard model (NLOW). The dashed black line represents the standard model prediction (NLOW) and the solid red line shows the result of the fit to the data.
biasscan_v2.png Simulated values of as a function of the measured . The black line represents the exact diagonal. The red line represents a fit of a first-order polynomial to the points.
pullwidth_v2.png Width of the pull distribution as a function of simulated values of . The red line represents a fit of a constant function to the points.

-- JeremyAndrea - 23 Jun 2014

Topic attachments
I Attachment History Action Size Date Who Comment
PDFpdf biasscan.pdf r1 manage 16.0 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng biasscan_v2.png r1 manage 43.4 K 2014-06-30 - 23:42 JeremyAndrea  
PDFpdf deltaphi_BSM.pdf r1 manage 19.2 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng deltaphi_BSM_v2.png r1 manage 34.9 K 2014-06-30 - 23:42 JeremyAndrea  
PDFpdf deltaphi_SM.pdf r1 manage 18.6 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng deltaphi_SM_v2.png r1 manage 34.2 K 2014-06-30 - 23:42 JeremyAndrea  
PDFpdf deltaphi_data_Fit_statPlusSyst.pdf r1 manage 15.6 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng deltaphi_data_Fit_statPlusSyst_v2.png r1 manage 51.8 K 2014-06-30 - 23:40 JeremyAndrea  
PDFpdf deltaphi_data_SM.pdf r1 manage 16.3 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng deltaphi_data_SM_v2.png r1 manage 60.5 K 2014-06-30 - 23:43 JeremyAndrea  
PDFpdf pullwidth.pdf r1 manage 15.5 K 2014-06-30 - 23:44 JeremyAndrea  
PNGpng pullwidth_v2.png r1 manage 27.4 K 2014-06-30 - 23:42 JeremyAndrea  
Edit | Attach | Watch | Print version | History: r9 < r8 < r7 < r6 < r5 | Backlinks | Raw View | WYSIWYG | More topic actions
Topic revision: r9 - 2014-07-23 - AndreasMeyer
    • Cern Search Icon Cern Search
    • TWiki Search Icon TWiki Search
    • Google Search Icon Google Search

    CMSPublic All webs login

This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2020 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback