Kazuki Sakurai

Physics at a 100 TeV pp collider: Higgs and EW symmetry breaking studies

Author(s): Contino, R; Curtin, D; Katz, A; Mangano, ML; Panico, G; Ramsey-Musolf, MJ; Zanderighi, G; Anastasiou, C; Astill, W; Bambhaniya, G; Behr, JK; Bizon, W; Dev, PS Bhupal; Bortoletto, D; Buttazzo, D; Cao, Q-H; Caola, F; Chakrabortty, J; Chen, C-Y; Chen, S-L; Florian, D de; Dulat, F; Englert, C; Frost, JA; Fuks, B; Gherghetta, T; Giudice, G; Gluza, J; Greiner, N; Gray, H; Hartland, NP; Issever, C; Jelinski, T; Karlberg, A; Kim, JH; Kling, F; Lazopoulos, A; Lee, SJ; Liu, Y; Luisoni, G; Mazzitelli, J; Mistlberger, B; Monni, P; Nikolopoulos, K; Mohapatra, RN; Papaefstathiou, A; Perelstein, M; Petriello, F; Plehn, T; Reimitz, P; Ren, J; Rojo, J; Sakurai, K; Schell, T; Sala, F; Selvaggi, M; Shao, H-S; Son, M; Spannowsky, M; Srivastava, T; Su, S-F; Szafron, R; Tait, T; Tesi, A; Thamm, A; Torrielli, P; Tramontano, F; Winter, J; Wulzer, A; Yan, Q-S; Yao, WM; Zhang, Y-C; Zhao, X; Zhao, Z; Zhong, Y-M | Abstract: This report summarises the physics opportunities for the study of Higgs bosons and the dynamics of electroweak symmetry breaking at the 100 TeV pp collider.This Chapter summarises the physics opportunities for the study of Higgs bosons and the dynamics of electroweak symmetry breaking at the 100 TeV pp collider.

Interpreting 750 GeV Diphoton Excess in Plain NMSSM

NMSSM has enough ingredients to explain the diphoton excess at 750 GeV: singlet-like (pseudo) scalar (a) s and higgsinos as heavy vector-like fermions. We consider the production of the 750 GeV singlet-like pseudo scalar a from a decay of the doublet-like pseudo scalar A, and the subsequent decay of a into two photons via higgsino loop. We demonstrate that this cascade decay of the NMSSM Higgs bosons can explain the diphoton excess at 750 GeV.

Simplified models of dark matter with a long-lived co-annihilation partner

A bstractWe introduce a new set of simplified models to address the effects of 3-point interactions between the dark matter particle, its dark co-annihilation partner, and the Standard Model degree of freedom, which we take to be the tau lepton. The contributions from dark matter co-annihilation channels are highly relevant for a determination of the correct relic abundance. We investigate these effects as well as the discovery potential for dark matter co-annihilation partners at the LHC. A small mass splitting between the dark matter and its partner is preferred by the co-annihilation mechanism and suggests that the co-annihilation partners may be long-lived (stable or meta-stable) at collider scales. It is argued that such long-lived electrically charged particles can be looked for at the LHC in searches of anomalous charged tracks. This approach and the underlying models provide an alternative/complementarity to the mono-jet and multi-jet based dark matter searches widely used in the context of simplified models with s-channel mediators. We consider four types of simplified models with different particle spins and coupling structures. Some of these models are manifestly gauge invariant and renormalizable, others would ultimately require a UV completion. These can be realised in terms of supersymmetric models in the neutralino-stau co-annihilation regime, as well as models with extra dimensions or composite models.

ATLAS diboson excess could be an

This work of B.C.A. has been partially supported by STFC grant ST/L000385/1. The work of P.S.B.D. is supported in part by a TUM University Foundation Fellowship and the DFG cluster of excellence “Origin and Structure of the Universe”.

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We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP,

Likelihood analysis of the minimal AMSB model

\tilde{\chi }^0_{1}

Search for Sphalerons in Proton-Proton Collisions

χ~10, may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces