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arXiv · 1411.7203

Measurements of $t\bar{t}$ spin correlations in CMS

Kelly Beernaert
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Abstract

We present an overview of the measurements of $t\bar{t}$ spin correlations in the CMS Collaboration. We present two analyses both in the dilepton channel using proton-proton collisions at $\sqrt{s}\, =\, 7$ TeV based on an integrated luminosity of 5.0 fb$^{-1}$. The spin correlations and polarization are measured using angular asymmetries. The results are consistent with unpolarized top quarks and Standard Model spin correlation. The second analysis sets a limit on the real part of the top-quark chromo-magnetic dipole moment of $-0.043\, <\, Re({\hatμ}_{t})\, <\, 0.117$ at $95\,%$ confidence level through the measured azimuthal angle difference between the two charged leptons from $t\bar{t}$ production.

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Kelly Beernaert. 2014-11-26. Measurements of $t\bar{t}$ spin correlations in CMS. https://arxiv.org/abs/1411.7203

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