scholarly journals Searching for heavy Higgs in supersymmetric final states at the LHC

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Amit Adhikary ◽  
Biplob Bhattacherjee ◽  
Rohini M. Godbole ◽  
Najimuddin Khan ◽  
Suchita Kulkarni
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Higgs Sector ◽  
Search Strategies ◽  
Final States ◽  
High Luminosity ◽  
The Standard Model ◽  
Extended Higgs Sector ◽  
Flavour Physics

Abstract In this work, we analyse and demonstrate possible strategies to explore extended Higgs sector of the Minimal Supersymmetric Standard Model (MSSM). In particular we concentrate on heavy Higgs decays to electroweakinos. We analyse the Higgs to electroweakino decays in the allowed MSSM parameter space after taking into account 13 TeV LHC searches for supersymmetric particles and phenomenological constraints such as flavour physics, Higgs measurements and dark matter constraints. We explore some novel aspects of these Higgs decays. The final states resulting from Higgs to electroweakino decays will have backgrounds arising from the Standard Model as well as direct electroweakino production at the LHC. We demonstrate explicit kinematical differences between Higgs to electroweakino decays and associated backgrounds. Furthermore, we demonstrate for a few specific example points, optimised analysis search strategies at the high luminosity LHC (HL-LHC) run. Finally, we comment on possible search strategies for heavy Higgs decays to exotic final states, where the lightest chargino is long lived and leads to a disappearing track at the LHC.

scholarly journals Signatures of Majorana dark matter with t-channel mediators

2015 ◽  
Vol 24 (07) ◽  
pp. 1530019 ◽  
Author(s):  
Mathias Garny ◽  
Alejandro Ibarra ◽  
Stefan Vogl
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Direct Detection ◽  
Dark Matter Particle ◽  
Search Strategies ◽  
Indirect Detection ◽  
Majorana Fermion ◽  
The Standard Model ◽  
Full Benefit ◽  
Near Future

Three main strategies are being pursued to search for nongravitational dark matter signals: direct detection, indirect detection and collider searches. Interestingly, experiments have reached sensitivities in these three search strategies which may allow detection in the near future. In order to take full benefit of the wealth of experimental data, and in order to confirm a possible dark matter signal, it is necessary to specify the nature of the dark matter particle and of the mediator to the Standard Model. In this paper, we focus on a simplified model where the dark matter particle is a Majorana fermion that couples to a light Standard Model fermion via a Yukawa coupling with a scalar mediator. We review the observational signatures of this model and we discuss the complementarity among the various search strategies, with emphasis in the well motivated scenario where the dark matter particles are produced in the early universe via thermal freeze-out.

scholarly journals PREDICTIONS FOR $B \to \tau \bar{\mu} + \mu \bar{\tau}$

2013 ◽  
Vol 28 (31) ◽  
pp. 1350153 ◽  
Author(s):  
DRIS BOUBAA ◽  
ALAKABHA DATTA ◽  
MURUGESWARAN DURAISAMY ◽  
SHAABAN KHALIL
Keyword(s):  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Neutral Current ◽  
Higgs Sector ◽  
New Physics ◽  
Flavor Changing ◽  
Clear Sign ◽  
Flavor Changing Neutral Current ◽  
Extended Higgs Sector

The observation of [Formula: see text] at present experiments would be a clear sign of new physics. In this paper, we calculate this process in an extended Higgs sector framework where the decay is mediated by the exchange of spin zero particle with flavor changing neutral current couplings. If we identify the scalar with the newly discovered state at LHC with a mass ~125 GeV then we find that, after imposing all experimental constraints, the [Formula: see text] can be as high as ~10-6 and [Formula: see text] can be as high as ~10-7. We also calculate this process in the minimal supersymmetric standard model and find the [Formula: see text] is typically of the order ~10-8.

scholarly journals SUPERSYMMETRIC U(1) GAUGE REALIZATION OF THE DARK SCALAR DOUBLET MODEL OF RADIATIVE NEUTRINO MASS

2008 ◽  
Vol 23 (10) ◽  
pp. 721-725 ◽  
Author(s):  
ERNEST MA
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Neutrino Mass ◽  
Dark Matter Candidate ◽  
Neutrino Masses ◽  
Particle Interactions ◽  
The Standard Model ◽  
Doublet Model

Adding a second scalar doublet (η+, η0) and three neutral singlet fermions N1, 2, 3 to the Standard Model of particle interactions with a new Z2 symmetry, it has been shown that [Formula: see text] or [Formula: see text] is a good dark-matter candidate and seesaw neutrino masses are generated radiatively. A supersymmetric U(1) gauge extension of this new idea is proposed, which enforces the usual R-parity of the Minimal Supersymmetric Standard Model, and allows this new Z2 symmetry to emerge as a discrete remnant.

scholarly journals Collider signatures of coannihilating dark matter in light of the B-physics anomalies

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Michael J. Baker ◽  
Darius A. Faroughy ◽  
Sokratis Trifinopoulos
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Bound States ◽  
B Physics ◽  
Search Strategy ◽  
Dark Matter Candidate ◽  
Final States ◽  
Dark Sector ◽  
Decay Modes ◽  
The Standard Model

Abstract Motivated by UV explanations of the B-physics anomalies, we study a dark sector containing a Majorana dark matter candidate and a coloured coannihilation partner, connected to the Standard Model predominantly via a U1 vector leptoquark. A TeV scale U1 leptoquark, which couples mostly to third generation fermions, is the only successful single-mediator description of the B-physics anomalies. After calculating the dark matter relic surface, we focus on the most promising experimental avenue: LHC searches for the coloured coannihilation partner. We find that the coloured partner hadronizes and forms meson-like bound states leading to resonant signatures at colliders reminiscent of the quarkonia decay modes in the Standard Model. By recasting existing dilepton and monojet searches we exclude coannihilation partner masses less than 280 GeV and 400 GeV, respectively. Since other existing collider searches do not significantly probe the parameter space, we propose a new dedicated search strategy for pair production of the coloured partner decaying into bbττ final states and dark matter particles. This search is expected to probe the model up to dark matter masses around 600 GeV with current luminosity.

HIGGS BOSONS

1990 ◽  
Vol 05 (26) ◽  
pp. 2087-2100 ◽  
Author(s):  
A. MÉNDEZ
Keyword(s):  
Standard Model ◽  
Higgs Sector ◽  
Higgs Bosons ◽  
Supersymmetric Model ◽  
The Standard Model ◽  
Doublet Model ◽  
Minimal Supersymmetric Model ◽  
Extended Higgs Sector

The main phenomenological aspects of the Higgs bosons are briefly reviewed in the context of the Standard Model and in models with an "extended" Higgs sector. Among the latter, special emphasis is made on the Two-Doublet Model and, particularly, the Minimal Supersymmetric Model.

scholarly journals Single-top final states as a probe of top-flavoured dark matter models at the LHC

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Monika Blanke ◽  
Priscilla Pani ◽  
Giacomo Polesello ◽  
Giulia Rovelli
Keyword(s):  
Dark Matter ◽  
Top Quark ◽  
Direct Detection ◽  
Final States ◽  
High Luminosity ◽  
Minimal Flavour Violation ◽  
Single Top ◽  
Discovery Potential ◽  
Flavour Violation ◽  
Flavour Physics

Abstract Models incorporating flavoured dark matter provide an elegant solution to the dark matter problem, evading the tight LHC and direct direction constraints on simple WIMP models. In Dark Minimal Flavour Violation, a simple framework of flavoured dark matter with new sources of flavour violation, the constraints from thermal freeze-out, direct detection experiments, and flavour physics create well-defined benchmark scenarios for these models. We study the LHC phenomenology of four such scenarios, focusing on final states where a single top quark is produced accompanied by no jets, one jet from the fragmentation of light quarks or a b-tagged jet. For each of these signatures we develop a realistic LHC analysis, and we show that the proposed analyses would increase the parameter space coverage for the four benchmarks, compared to existing flavour-conserving LHC analyses. Finally we show the projected discovery potential of the considered signatures for the full LHC statistics at 14 TeV, and for the High Luminosity LHC.

scholarly journals Forbidden dark matter annihilations into Standard Model particles

2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Raffaele Tito D’Agnolo ◽  
Di Liu ◽  
Joshua T. Ruderman ◽  
Po-Jen Wang
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Relevant Parameter ◽  
Annihilation Rate ◽  
High Luminosity ◽  
Muon Mass ◽  
Electron Positron ◽  
Dark Matter Mass ◽  
The Standard Model ◽  
Relic Abundance

Abstract We present kinematically forbidden dark matter annihilations into Standard Model leptons. This mechanism precisely selects the dark matter mass that gives the observed relic abundance. This is qualitatively different from existing models of thermal dark matter, where fixing the relic density typically leaves open orders of magnitude of viable dark matter masses. Forbidden annihilations require the dark matter to be close in mass to the particles that dominate its annihilation rate. We show examples where the dark matter mass is close to the muon mass, the tau mass, or the average of the tau and muon masses. We find that most of the relevant parameter space can be covered by the next generation of proposed beam-dump experiments and future high-luminosity electron positron colliders. Forbidden dark matter predicts large couplings to the Standard Model that can explain the observed value of (g − 2)μ.

scholarly journals On the D*s and charmonia leptonic decays

2018 ◽  
Vol 175 ◽  
pp. 13002
Author(s):  
Gabriela Bailas ◽  
Benoît Blossier ◽  
Jochen Heitger ◽  
Vincent Morénas ◽  
Matthias Post
Keyword(s):  
Large Range ◽  
Chiral Limit ◽  
Higgs Sector ◽  
New Physics ◽  
Decay Constants ◽  
Leptonic Decays ◽  
The Standard Model ◽  
Extended Higgs Sector ◽  
Flavour Physics

Among the different scenarios of New Physics, those with an extended Higgs sector are examined with a lot of attention. Recent experimental observations of several anomalies in flavour physics with respect to expectations of the Standard Model further motivate the effort of phenomenologists. First, informations about the RDs ratio, a test of lepton flavour universality equivalent to RD, already measured, but with the s quark as spectator, are awaited in coming years to constrain the corner of an extended Higgs sector with charged doublets. On another side, leptonic widths of pseudoscalar quarkonia are particularly interesting to test an extended Higgs sector with a light CP-odd Higgs boson singlet, through the study of its mixing with quarkonia states. Hadronic parameters entering those processes have to be determined from lattice QCD with enough confidence on the control of systematic errors. We report on the very first step of a long-term program tackled with Nf = 2 Wilson-Clover fermions to put relevant constraints on extensions of the Higgs sector: extraction of decay constants of D*s, ƞc, ƞc (2S), J/Ψ and Ψ(2S) with lattice ensembles provided by the CLS effort, considering 2 lattice spacings and a large range of pion masses to estimate cut-off effects and extrapolate results to the chiral limit.

scholarly journals Searches for new phenomena with the ATLAS detector

2020 ◽  
Vol 35 (34n35) ◽  
pp. 2044005
Author(s):  
Francesco Guescini
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
New Physics ◽  
Atlas Detector ◽  
Beyond The Standard Model ◽  
High Luminosity ◽  
Atlas Experiment ◽  
The Standard Model ◽  
New Phenomena

Many theories beyond the Standard Model predict new phenomena accessible by the Lhc. Searches for new physics are performed using the Atlas experiment at the Lhc focusing on exotic signatures that are predicted in several theories, excluding supersymmetry. The results of recent searches using 13 TeV data, with the exception of those for Dark Matter signatures, and their interplay and interpretation are presented. Prospects for searches at the High Luminosity Lhc are also discussed.

Sign in / Sign up

Export Citation Format

Share Document