Abstract
We consider the phenomenology of CP violation in a color-octet extended scalar sector for t \( \overline t \) production and decay at the LHC. In particular we study the effect of the two neutral color-octet scalars S I and S R that occur in the model. There are two new sources of CP violation: a phase in the couplings of S I,R to top-quarks; and two phases in the quartic couplings of the scalar potential. In resonant production of a single S I,R followed by its decay into t \( \overline t \) pairs through the parton level process gg → S I,R → t \( \overline t \), we find large raw CP asymmetries which can reach 12%. These raw asymmetries are, of course, diluted by standard model (SM) t \( \overline t \) pairs making observation of CP violation contingent on whether the resonance itself can be extracted from the SM background.
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ArXiv ePrint: 1110.2588
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He, XG., Valencia, G. & Yokoya, H. Color-octet scalars and potentially large CP violation at the LHC. J. High Energ. Phys. 2011, 30 (2011). https://doi.org/10.1007/JHEP12(2011)030
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DOI: https://doi.org/10.1007/JHEP12(2011)030