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The interference between the $K^+K^-$ S-wave and P-wave amplitudes in $B_s \rightarrow J/\psi K^+K^-$ decays with the $K^+K^-$ pairs in the region around the $\phi(1020)$ resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of $K^+K^-$ invariant mass. Combined with the results from our $CP$ asymmetry measurements in the $B_s \rightarrow J/\psi \phi$ decays, we conclude that the $B_s$ mass eigenstate that is almost $CP =+1$ is lighter and decays faster than the mass eigenstate that is almost $CP =-1$. This determines the sign of the decay width difference $\Delta\Gamma_s \equiv \Gamma_L -\Gamma_H$ to be positive. Our result also resolves the ambiguity in the past measurements of the $CP$ violating phase $\phi_s$ to be close to zero rather than $\pi$. These conclusions are in agreement with the Standard Model expectations. The interference between the K+K- S-wave and P-wave amplitudes in B_s -> J/psi K+K- decays with the K+K- pairs in the region around the phi(1020) resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of K+K- invariant mass. Combined with the results from our CP asymmetry measurements in B_s -> J/psi phi decays, we conclude that the B_s mass eigenstate that is almost CP =+1 is lighter and decays faster than the mass eigenstate that is almost CP =-1. This determines the sign of the decay width difference DeltaGamma_s == Gamma_L -Gamma_H to be positive. Our result also resolves the ambiguity in the past measurements of the CP violating phase phi_s to be close to zero rather than pi. These conclusions are in agreement with the Standard Model expectations.

Large classes of new physics theories predict the existence of new scalar states, commonly dubbed sgluons, lying in the adjoint representation of the QCD gauge group. Since these new fields are expected to decay into colored Standard Model particles, and in particular into one or two top quarks, these theories predict a possible enhancement of the hadroproduction rate associated with multitop final states. We therefore investigate multitop events produced at the Large Hadron Collider, running at a center-of-mass energy of 8 TeV, and employ those events to probe the possible existence of color adjoint scalar particles. We first construct a simplified effective field theory motivated by R-symmetric supersymmetric models where sgluon fields decay dominantly into top quarks. We then use this model to analyze the sensitivity of the Large Hadron Collider in both a multilepton plus jets and a single lepton plus jets channel. After having based our event selection strategy on the possible presence of two, three and four top quarks in the final state, we find that sgluon-induced new physics contributions to multitop cross sections as low as 10-100 fb can be excluded at the 95% confidence level, assuming an integrated luminosity of 20 inverse fb. Equivalently, sgluon masses of about 500-700 GeV can be reached for several classes of benchmark scenarios.

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