scholarly journals Leptoquarks and real singlets: A richer scalar sector behind the origin of dark matter

2021 ◽  
Vol 104 (1) ◽  
Author(s):  
Francesco D’Eramo ◽  
Nejc Košnik ◽  
Federico Pobbe ◽  
Aleks Smolkovič ◽  
Olcyr Sumensari
Keyword(s):  
2018 ◽  
Vol 33 (10n11) ◽  
pp. 1830007 ◽  
Author(s):  
Agnieszka Ilnicka ◽  
Tania Robens ◽  
Tim Stefaniak

We give a brief overview of beyond the Standard Model (BSM) theories with an extended scalar sector and their phenomenological status in the light of recent experimental results. We discuss the relevant theoretical and experimental constraints, and show their impact on the allowed parameter space of two specific models: the real scalar singlet extension of the Standard Model (SM) and the Inert Doublet Model. We emphasize the importance of the LHC measurements, both the direct searches for additional scalar bosons, as well as the precise measurements of properties of the Higgs boson of mass 125 GeV. We show the complementarity of these measurements to electroweak and dark matter observables.


2006 ◽  
Vol 73 (1) ◽  
pp. 142-148 ◽  
Author(s):  
S Filippi ◽  
W. A Ponce ◽  
L. A Sánchez
Keyword(s):  

Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2341
Author(s):  
Tania Robens

The THDMa is a new physics model that extends the scalar sector of the Standard Model by an additional doublet as well as a pseudoscalar singlet and allows for mixing between all possible scalar states. In the gauge-eigenbasis, the additional pseudoscalar serves as a portal to the dark sector, with a priori any dark matter spins states. The option where dark matter is fermionic is currently one of the standard benchmarks for the experimental collaborations, and several searches at the LHC constrain the corresponding parameter space. However, most current studies constrain regions in parameter space by setting all but 2 of the 12 free parameters to fixed values. In this work, we performed a generic scan on this model, allowing all parameters to float. We applied all current theoretical and experimental constraints, including bounds from current searches, recent results from B-physics, in particular Bs→Xsγ, as well as bounds from astroparticle physics. We identify regions in the parameter space which are still allowed after these were applied and which might be interesting for an investigation of current and future collider machines.


2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Cheng-Wei Chiang ◽  
Giovanna Cottin ◽  
Yong Du ◽  
Kaori Fuyuto ◽  
Michael J. Ramsey-Musolf

Abstract We study discovery prospects for a real triplet extension of the Standard Model scalar sector at the Large Hadron Collider (LHC) and a possible future 100 TeV pp collider. We focus on the scenario in which the neutral triplet scalar is stable and contributes to the dark matter relic density. When produced in pp collisions, the charged triplet scalar decays to the neutral component plus a soft pion or soft lepton pair, yielding a disappearing charged track in the detector. We recast current 13 TeV LHC searches for disappearing tracks, and find that the LHC presently excludes a real triplet scalar lighter than 248 (275) GeV, for a mass splitting of 172 (160) MeV with ℒ = 36 fb−1. The reach can extend to 497 (520) GeV with the collection of 3000 fb−1. We extrapolate the 13 TeV analysis to a prospective 100 TeV pp collider, and find that a ∼ 3 TeV triplet scalar could be discoverable with ℒ = 30 ab−1, depending on the degree to which pile up effects are under control. We also investigate the dark matter candidate in our model and corresponding present and prospective constraints from dark matter direct detection. We find that currently XENON1T can exclude a real triplet dark matter lighter than ∼ 3 TeV for a Higgs portal coupling of order one or larger, and the future XENON20T will cover almost the entire dark matter viable parameter space except for vanishingly small portal coupling.


2017 ◽  
Vol 32 (10) ◽  
pp. 1750038 ◽  
Author(s):  
Mitsuru Kakizaki ◽  
Akiteru Santa ◽  
Osamu Seto

We discuss phenomenological aspects of models whose scalar sector is extended by an isospin doublet scalar and a complex singlet scalar as an effective theory of supersymmetric models with mixed sneutrinos. In such models, the lighter of the mixed neutral scalars can become a viable dark matter (DM) candidate by imposing a global U(1) symmetry. We find that the thermal WIMP scenario is consistent with the cosmological DM abundance when the mass of the scalar is half of that of the discovered Higgs boson or larger than around 100 GeV. We also point out that, with an additional isospin singlet Majorana fermion mediator, even the mass of the scalar WIMP less than around 5 GeV is compatible with the observed DM abundance. We show that such cosmologically allowed regions can be explored at future collider experiments and DM detections.


2020 ◽  
Vol 2020 (12) ◽  
Author(s):  
Cao H. Nam ◽  
Duong Van Loi ◽  
Le Xuan Thuy ◽  
Phung Van Dong

Abstract It is shown that for a higher weak isospin symmetry, SU(P)L with P ≥ 3, the baryon minus lepton charge B − L neither commutes nor closes algebraically with SU(P)L similar to the electric charge Q, which all lead to a SU(3)C ⊗ SU(P)L ⊗ U(1)X ⊗ U(1)N gauge completion, where X and N determine Q and B − L, respectively. As a direct result, the neutrinos obtain appropriate masses via a canonical seesaw. While the version with P = 3 supplies the schemes of single-component dark matter well established in the literature, we prove in this work that the models with P ≥ 4 provide the novel scenarios of multicomponent dark matter, which contain simultaneously at least P−2 stable candidates, respectively. In this setup, the multicomponet dark matter is nontrivially unified with normal matter by gauge multiplets, and their stability is ensured by a residual gauge symmetry which is a remnant of the gauge symmetry after spontaneous symmetry breaking. The three versions with P = 4 according to the new lepton electric charges are detailedly investigated. The mass spectrum of the scalar sector is diagonalized when the scale of the U(1)N breaking is much higher than that of the usual 3-4-1 symmetry breaking. All the interactions of gauge bosons with fermions and scalars are obtained. We figure out viable parameter regimes given that the multicomponent dark matter satisfies the Planck and (in)direct detection experiments.


2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
David Curtin ◽  
Shayne Gryba

Abstract Many minimal models of dark matter (DM) or canonical solutions to the hierarchy problem are either excluded or severely constrained by LHC and direct detection null results. In particular, Higgs Portal Dark Matter (HPDM) features a scalar coupling to the Higgs via a quartic interaction, and obtaining the measured relic density via thermal freeze-out gives definite direct detection predictions which are now almost entirely excluded. The Twin Higgs solves the little hierarchy problem without coloured top partners by introducing a twin sector related to the Standard Model (SM) by a discrete symmetry. We generalize HPDM to arbitrary Twin Higgs models and introduce Twin Higgs Portal Dark Matter (THPDM), which features a DM candidate with an SU(4)-invariant quartic coupling to the Twin Higgs scalar sector. Given the size of quadratic corrections to the DM mass, its most motivated scale is near the mass of the radial mode. In that case, DM annihilation proceeds with the full Twin Higgs portal coupling, while direct detection is suppressed by the pNGB nature of the 125 GeV Higgs. For a standard cosmological history, this results in a predicted direct detection signal for THPDM that is orders of magnitude below that of HPDM with very little dependence on the precise details of the twin sector, evading current bounds but predicting possible signals at next generation experiments. In many Twin Higgs models, twin radiation contributions to ∆Neff are suppressed by an asymmetric reheating mechanism. We study this by extending the νMTH and X MTH models to include THPDM and compute the viable parameter space according to the latest CMB bounds. The injected entropy dilutes the DM abundance as well, resulting in additional suppression of direct detection below the neutrino floor.


Sign in / Sign up

Export Citation Format

Share Document