10 research outputs found

    Singlet-doublet/triplet dark matter and neutrino masses

    Full text link
    In these proceedings, we present a study of a combined singlet--doublet fermion and triplet scalar model for dark matter (DM). Together, these models form a simple extension of the Standard Model (SM) that can account for DM and explain the existence of neutrino masses, which are generated radiatively. However, this also implies the existence of lepton flavour violating (LFV) processes. In addition, this particular model allows for gauge coupling unification. The new fields are odd under a new Z2\mathbb{Z}_2 symmetry to stabilise the DM candidate. We analyse the DM, neutrino mass and LFV aspects, exploring the viable parameter space of the model. This is done using a numerical random scan imposing successively the neutrino mass and mixing, relic density, Higgs mass, direct detection, collider and LFV constraints. We find that DM in this model is fermionic for masses below about 1 TeV and scalar above. We observe a high degree of complementarity between direct detection and LFV experiments, which should soon allow to fully probe the fermionic DM sector and at least partially the scalar DM sector.Comment: 4 pages, 1 figure; contribution to the 2019 EW session of the 54th Rencontres de Moriond (summary of arXiv:1812.11133

    Electroweak Phase Transition, Gravitational Waves and Dark Matter in Two Scalar Singlet Extension of The Standard Model

    Full text link
    In this paper, the electroweak phase transition, the gravitational waves and the dark matter issues are investigated in two scalar singlet extension of the standard model. The detectability of the gravitational wave signals are discussed by comparing the results with the sensitivity curves of eLISA\mathbf{eLISA}, ALIA\mathbf{ALIA}, DECIGO\mathbf{DECIGO} and BBO\mathbf{BBO} detectors. It is shown that the results support the recent reports on the dark matter relic density by Planck\mathbf{Planck} 2018\mathbf{2018} collaboration and the direct detection experiment by XENON1T\mathbf{XENON1T} 2018\mathbf{2018} collaboration.Comment: 18 pages, 2 figures (4 subfigures), 4 tables, final version to match the published versio

    Investigating extended scalar sectors at current and future colliders

    Get PDF
    In this work, I briefly report on constraints that can be obtained on new physics models that extend the scalar sector of the Standard Model (SM) of particle physics at the LHC. I concentrate on a few simple examples which serve to demonstrate advantages as well as possible drawbacks of current experimental searches, and comment on the discovery prospects of such models at future colliders

    Singlet-doublet fermion and triplet scalar dark matter with radiative neutrino masses

    Full text link
    We present a detailed study of a combined singlet-doublet fermion and triplet scalar model for dark matter. These models have only been studied separately in the past. Together, they form a simple extension of the Standard Model that can account for dark matter and explain the existence of neutrino masses, which are generated radiatively. This holds even if singlet-doublet fermions and triplet scalars never contribute simultaneously to the dark matter abundance. However, this also implies the existence of lepton flavour violating processes. In addition, this particular model allows for gauge coupling unification. The new fields are odd under a new Z2\mathbb{Z}_2 symmetry to stabilise the dark matter candidate. We analyse the dark matter, neutrino mass and lepton flavour violation aspects both separately and in conjunction, exploring the viable parameter space of the model. This is done using a numerical random scan imposing successively the neutrino mass and mixing, relic density, Higgs mass, direct detection, collider and lepton flavour violation constraints. We find that dark matter in this model is fermionic for masses below about 1 TeV and scalar above. The narrow mass regions found previously for the two separate models are enlarged by their coupling. While coannihilations of the weak isospin partners are sizeable, this is not the case for fermions and scalars despite their often similar masses due to the relatively small coupling of the two sectors, imposed by the small neutrino masses. We observe a high degree of complementarity between direct detection and lepton flavour violation experiments, which should soon allow to fully probe the fermionic dark matter sector and at least partially the scalar dark matter sector.Comment: 24 pages, 12 figures; version accepted by and published in JHE

    Review on Dark Matter Tools

    Full text link
    Whilst the need for dark matter was established almost a century ago, only its gravitational interaction has been confirmed so far, allowing for plethora of models for dark matter. The Weakly Interacting Massive Particles (WIMPs) category has received by far the biggest attention, however despite the enormous experimental efforts, these particles remain elusive. The attention of the community has hence moved on to investigate the dark matter landscape over a much larger number of models with varying degrees of resemblances and differences in their predictions. This calls for the need to organise the various facets of dark matter models and their signatures, in order to maximise the experimental sensitivity and to select the models which are compatible with existing data. In this paper, I provide a short review of the most widespread public codes capable of computing dark matter observables. In particular, I discuss what is the status of each numerical tool in terms of: (i) capturing the WIMP phenomenology and (ii) accounting for new trend dark sector models that might be weakly coupled to ordinary matter and/or be strongly self-interacting. This short review has the aim of guiding the user towards selecting the best suited public code to confront his/her model with the largest variety of theoretical predictions and experimental data in order to determine the parameter space consistent with observations for his/her favourite dark matter model.Comment: 9 pages + references; matches the published version (only few references added) into "Tools for High Energy Physics and Cosmology" (TOOLS2020), 2-6 Nov. 2020, IP2I Lyon, Franc

    Characterizing dark matter interacting with extra charged leptons

    Get PDF
    In the context of a simplified leptophilic dark matter (DM) scenario where the mediator is a new charged fermion carrying leptonic quantum number and the DM candidate is either scalar or vector, the complementarity of different bounds is analyzed. In this framework, the extra lepton and DM are odd under a Z2 symmetry, and hence the leptonic mediator can only interact with the DM state and Standard Model leptons of various flavors. We show that there is the possibility to characterize the DM spin (scalar or vector), as well as the nature of the mediator, through a combined analysis of cosmological, flavor and collider data. We present an explicit numerical analysis for a set of benchmarks points of the viable parameter space of our scenario
    corecore