Dr
Xabier Marcano
(LPT Orsay)
22/05/2018, 14:00
Heavy neutral leptons or massive sterile neutrinos are present in many well-motivated beyond the Standard Model theories, sometimes being accesible at present colliders. Our aim is to discuss the potential of the LHC to produce and discover this kind of new particles when their masses are in the GeV range. Moreover, and depending on their masses and couplings, they can be long-lived and lead...
Simon Zeren Wang
(bctp, Bonn University)
22/05/2018, 14:20
Long-lived light particles (LLLPs) appear in many extensions of the standard model. LLLPs are usually motivated by the observed small neutrino masses, by dark matter or both. Typical examples for fermionic LLLPs (a.k.a. heavy neutral fermions, HNFs) are sterile neutrinos or the lightest neutralino in R-parity violating supersymmetry. The high luminosity LHC is expected to deliver up to 3/ab of...
Carlos Tamarit
(Technische Universität München)
22/05/2018, 14:40
Chiral electroweak anomalies predict fermion interactions that violate baryon (B) and lepton number (L), and can be dressed with large numbers of Higgs and gauge bosons. The estimation of the total B+L violating rate from an initial two-particle state --potentially observable at colliders-- has been the subject of an intense discussion, mainly centered on the resummation of boson emission,...
Claudia Garcia-Garcia
(IFT-UAM/CSIC)
22/05/2018, 15:30
The electroweak symmetry breaking (EWSB) sector still keeps some mysteries under the sleeve. Questions such as what is the dynamical origin of EWSB, what is the true nature of the Higgs boson or are the properties of this particle the ones predicted in the SM remain unanswered. The LHC is our tool to unveil these mysteries and vector boson scattering (VBS) is the perfect window to access them....
Ken Mimasu
(Université catholique de Louvain)
22/05/2018, 15:50
The Standard Model Effective Field Theory (SMEFT) provides a consistent formalism to parametrise the effects of heavy new physics appearing as deviations from SM expectations. One of the key goals of the LHC legacy will be to cover this parameter space as much as possible and contribute to a global fit of the EFT parameter space and, hopefully, provide hints on the nature of physics beyond the...
Prof.
Margarete Mühlleitner
(KIT)
23/05/2018, 14:40
The generation of the observed matter-antimatter asymmetry in the universe through baryogenesis cannot be explained in the Standard Model. We therefore investigate the possibility of a strong first order phase transition in the CP-Violating 2-Higgs-Doublet Model (C2HDM) after imposing theoretical and experimental constraints. We study the type I and II C2HDM where one of the neutral Higgs...
Hugues Beauchesne
(University of Sao Paulo)
23/05/2018, 15:00
Many models of Beyond the Standard Model physics contain particles that are charged under both Standard Model and Hidden Valley gauge groups, yet very little effort has been put into establishing their experimental signatures. We provide a general overview of the collider phenomenology of spin 0 or 1/2 mediators with non-trivial gauge numbers under both the Standard Model and a single new...
Mr
Daniel Dercks
(University of Hamburg)
23/05/2018, 16:10
We scrutinize the allowed parameter space of Little Higgs models with the concrete symmetry of T-parity by providing comprehensive LHC analyses of all relevant production channels of heavy vectors, top partners, heavy quarks and heavy leptons and all phenomenologically relevant decay channels. Constraints on the model will be derived from the signatures of jets and missing energy or leptons...
Ipsita Saha
(INFN, Roma 1)
23/05/2018, 16:30
Contrary to common perception, we show that the current Higgs data does not eliminate the possibility of a sequential fourth generation that get their masses through the same Higgs mechanism as the first three generations. The inability to fix the sign of the bottom-quark Yukawa coupling from the available data plays a crucial role in accommodating a chiral fourth generation which is...
Dr
Sebastian Paßehr
(LPTHE)
23/05/2018, 16:50
The decays of neutral Higgs bosons into Standard Model fermions and gauge-bosons in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) are investigated at the full one-loop order with some higher-order QCD corrections. We take mixing effects for the external Higgs particles consistently into account. In the beginning, some formal aspects of our approach are discussed, before we compare...
Dr
Thomas Flacke
(IBS CTPU)
23/05/2018, 17:10
Many Standard Model extensions that address the hierarchy problem contain Dirac-fermion partners of the top quark, which are typically expected around the TeV scale. Searches for these vector-like quarks mostly focus on their decay into electroweak gauge bosons or Higgs plus a standard model quark. In this talk, backed by models of composite Higgs, we propose a set of simplified scenarios that...
Prof.
Ilya Ginzburg
(Sobolev Institute of Mathematics)
23/05/2018, 17:30
3 topics appeared in the description of processes with unstable particles. 1. Plane wave formalism is insufficient for some realistic problems. The wave packets formalism become necessary. Illustration:The t--channel singularity in small angle scattering. 2. Perturbation series become invalid like in the case of infrared divergence in QED, but in more strong form. Illustration: The s--channel...