We show that new resonance shapes -a pure dip, nothingness and an enhanced pure peakcan be produced from the interference between resonance and continuum with a relative phase. Production conditions of those new shapes are derived based on a general parameterization of the interference. The narrow width approximation is modified to work with the non-zero imaginary part of interference, and the correction factor can characterize the resonance shape. We demonstrate that the new resonance shapes of heavy Higgs bosons, H 0 and A 0 in the Type II aligned two Higgs doublet model, generally show up in gg → H 0 /A 0 → tt as well as bb and γγ channels. The pure A 0 resonance dip in the tt channel is a particularly interesting signal as it can be probed well by the current search techniques that do not even take into account interferences; the high-luminosity LHC 14 TeV can perhaps probe a large part of its parameter space.

Although the Large Hadron Collider (LHC) has not observed supersymmetric (SUSY) partners of the Standard Model particles, their existence is not ruled out yet. One recently explored scenario in which there are light SUSY partners that have evaded current bounds from the LHC is that of a light long-lived stop quark. In this paper we consider light stop pair production at the LHC when the stop mass is between 200 and 400 GeV. If the stops are long-lived they can form a bound state, stoponium, which then undergoes two-body decays to Standard Model particles. By considering the near-threshold production of such a pair through the gluon-gluon fusion process and taking into account the strong Coulombic interactions responsible for the formation of this bound state, we obtain factorization theorems for the stop pair inclusive and differential production cross sections. We also perform a resummation of large threshold logarithms up to next-to-next-toleading logarithmic accuracy using well-established renormalization group equations in an effective field theory methodology. These results are used to calculate the invariant mass distributions of two photons or two Z bosons coming from the decay of the stoponium at the LHC. For our choices of SUSY model parameters, the stoponium is not detectable above Standard Model backgrounds in γγ or ZZ at 8 TeV, but will be visible with 400 fb −

Abstract:The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on H-tc Yukawa coupling λ ct within the general two Higgs doublet model. After electroweak symmetry breaking the top quark FCNC couplings are included in the charged Higgs Yukawa sector so that they contribute to various processes in flavor physics. To probe λ ct , we study anomalous single top production and the same sign top pair production at the LHC in association with flavor physics from the tree-level processes B → D ( * ) τ ν, B → τ ν as well as from the loop-level processes B d → X s γ, B d,s − B d,s mixing. We perform combined analysis of all the constraints regarding the fine-tuning argument to fit the data and discuss future prospect. The recently updated measurements on B → D ( * ) τ ν still prefer large λ ct , but we show that the current bound on the same sign top pair production at the LHC gives the most significant upper bound on λ ct to be less than 10 ∼ 30 depending on neutral heavy Higgs masses. We also find that for the given upper bound on λ ct , B → D ( * ) τ ν put significant lower bound on H-τ -τ Yukawa coupling, and the bound is proportional to the charged Higgs mass.

We compute the order α 2 s correction to the matrix element of magnetic penguin operator for B meson decaying to light mesons within the QCD factorization framework. We explicitly show that the soft and collinear divergences are canceled out, so that the validity of QCD factorization is confirmed. We present the result of the calculation in complete analytic forms. The result is also applied to B → Kπ decays, and we find that the order α 2 s correction of magnetic penguin operator can considerably reduce the coefficient of penguin amplitude a c 4,I . The reduction is stronger for the imaginary part.