Search for high mass resonances in the diphoton and Z+photon channels at LHC

• R. Paramatti (INFN Sezione di Roma)
• M. Bauce (INFN Sezione di Roma)

Room: Aula Conversi The Run 2 of the LHC opens a window on new physics searches thanks to the higher center-of-mass collision energy. Searches for high mass resonances were among the first carried out by ATLAS and CMS collaborations with few inverse femtobarn of data collected by the end of 2015. An excess in the data with respect to the Standard Model prediction in diphoton events was reported by both experiments at 750 GeV few months ago, though not statistically significant. We review those results and their integration with related searches in Z+photon final states, in the context of a scalar resonance and of a spin-2 model.

Flavour anomalies in b-hadron decays

• N. Serra (Univ. Zurigo)

Room: Aula Conversi Recently, some deviations with respect to Standard Model predictions in rare B-meson decays have been measured by the LHCb experiment. These deviations consist of angular observables in the $B^0\to K^*\mu^+\mu^-$ decay, branching ratio measurements of $b\to s\mu^+ \mu^-$ transitions and the ratio of the branching ratios $R_K=\frac{B^+\to K^+\mu^+\mu^-}{B^+\to K^+ e^+ e^-}$. Intriguingly, these anomalies seem to form a coherent pattern. I will discuss the experimental measurements of these observables and their interpretation, including theory uncertainties and future prospects. Finally, I will present measurements of the ratio of the branching ratio of the decays $B\to D^{(*)} \tau \nu$ and $B\to D^{(*)} \mu \nu$, which show significant deviations from lepton universality and Standard Model predictions. I will discuss the experimental measurements by BaBar, Belle and LHCb and future prospects.

A possible explanation of diphoton and flavor anomalies.

• G: Isidori (Univ. Zurigo)

Room: Aula Conversi A coherent explanation for the 750 GeV diphoton anomaly and the hints of deviations from Lepton Flavor Universality in B decays can be obtained in terms a new strongly interacting sector with vector-like confinement. The diphoton excess arises from the decay of one of the pseudo-Nambu-Goldstone bosons of the new sector, while the flavor anomalies are a manifestation of the exchange of the corresponding vector resonances (with masses in the 1.5-2.5 TeV range). I will present some explicit examples (with detailed particle content and group structure) of the new sector, discussing both the low-energy flavor-physics phenomenology and the signatures at high pT. A key feature of all realizations is a sizable broad excess in the tails of inclusive production of tau+tau- and b-b-bar pairs in pp collisions that should be accessible at the LHC in the near future.