Scalar assisted singlet doublet fermion dark matter model and electroweak vacuum stability
TL;DR: In this paper, the authors extend the so-called singlet doublet dark matter model, where the dark matter is an admixture of a Standard Model singlet and a pair of electroweak doublet fermions, by a singlet scalar field.
Abstract: We extend the so-called singlet doublet dark matter model, where the dark matter is an admixture of a Standard Model singlet and a pair of electroweak doublet fermions, by a singlet scalar field. The new portal coupling of it with the dark sector not only contributes to the dark matter phenomenology (involving relic density and direct detection limits) but also becomes important for generation of dark matter mass through its vacuum expectation value. While the presence of dark sector fermions affects the stability of the electroweak vacuum adversely, we find this additional singlet is capable of making the electroweak vacuum absolutely stable up to the Planck scale. A combined study of dark matter phenomenology and the Higgs vacuum stability issue reflects that the scalar sector mixing angle can be significantly constrained in this scenario.
Citations
More filters
TL;DR: In this article , a type II seesaw model for light Dirac neutrinos was proposed to provide an explanation for the recently reported anomaly in W boson mass by the CDF collaboration with $7\sigma$ statistical significance.
58 citations
TL;DR: In this article, a minimal extension of the Standard Model to accommodate two-component dark matter (DM) and light neutrino mass was proposed, where the symmetry of the standard model was enhanced by an unbroken assumption that being odd under each sector, there exists one right-handed neutrinos and one inert scalar doublet.
Abstract: We propose a minimal extension of the Standard Model to accommodate two-component dark matter (DM) and light neutrino mass. The symmetry of the Standard Model is enhanced by an unbroken ${\mathbb{Z}}_{2}\ifmmode\times\else\texttimes\fi{}{\mathbb{Z}}_{2}^{\ensuremath{'}}$ such that being odd under each ${\mathbb{Z}}_{2}$, there exists one right-handed neutrino and one inert scalar doublet. Therefore, each of the ${\mathbb{Z}}_{2}$ sectors contribute to (i) light neutrino masses radiatively similar to the scotogenic models while (ii) the two neutral $CP$ even scalars present in two additional inert doublets play the role of dark matters. Focusing on the intermediate range of inert scalar doublet DM scenario: ${M}_{W}\ensuremath{\le}{M}_{\mathrm{DM}}\ensuremath{\lesssim}\phantom{\rule{0ex}{0ex}}500\text{ }\text{ }\mathrm{GeV}$, where one scalar doublet DM cannot satisfy correct relic, we show that this entire range becomes allowed within this two-component scalar doublet DM, thanks to the interconversion between the two DM candidates in the presence of neutrino Yukawa couplings with dark sector.
49 citations
TL;DR: In this paper, the authors proposed a B − L model with three fermion triplets and showed that the leftover triangle anomalies can be cancelled by two neutral Dirac fermions having fractional B − l charges, both of which are naturally stable by virtue of a remnant ℤ2×676 $$ {\mathbb{Z}_2^{\prime } $$ symmetry.
Abstract: We propose a B − L gauged extension of the Standard Model where light neutrino masses arise from type III seesaw mechanism. Unlike the minimal B − L model with three right handed neutrinos having unit lepton number each, the model with three fermion triplets is however not anomaly free. We show that the leftover triangle anomalies can be cancelled by two neutral Dirac fermions having fractional B − L charges, both of which are naturally stable by virtue of a remnant ℤ2×
$$ {\mathbb{Z}}_2^{\prime } $$
symmetry, naturally leading to a two component dark matter scenario without any ad-hoc symmetries. We constrain the model from all relevant phenomenological constraints including dark matter properties. Light neutrino mass and collider prospects are also discussed briefly. Due to additional neutral gauge bosons, the fermion triplets in type III seesaw can have enhanced production cross section in collider experiment.
40 citations
TL;DR: In this paper, the authors proposed a Dirac-type neutrino model where light neutrinos are of Dirac type, naturally acquiring sub-eV mass after electroweak symmetry breaking, without any additional global symmetries.
Abstract: We propose a new gauged $$B-L$$ extension of the standard model where light neutrinos are of Dirac type, naturally acquiring sub-eV mass after electroweak symmetry breaking, without any additional global symmetries. This is realised by choosing a different $$B-L$$ charge for right handed neutrinos than the usual $$-1$$ so that the Dirac Yukawa coupling involves an additional neutrinophilic scalar doublet instead of the usual Higgs doublet. The model can be made anomaly free by considering four additional chiral fermions which give rise to two massive Dirac fermions by appropriate choice of singlet scalars. The choice of scalars not only helps in achieving the desired particle mass spectra via spontaneous symmetry breaking, but also leaves a remnant $$Z_2 \times Z'_2$$ symmetry to stabilise the two dark matter candidates. Apart from this interesting link between Dirac nature of light neutrinos and multi-component dark matter sector, we also find that the dark matter parameter space is constrained mostly by the cosmological upper limit on effective relativistic degrees of freedom $$\Delta N_{\mathrm{eff}}$$ which gets enhanced in this model due to the thermalisation of the light right handed neutrinos by virtue of their sizeable $$B-L$$ gauge interactions.
32 citations
TL;DR: In this paper , an extension of the minimal gauged model with three right-handed singlet fermions and a scalar doublet was proposed to explain the anomalous magnetic moments of muon and electron simultaneously.
Abstract: We study an extension of the minimal gauged ${L}_{\ensuremath{\mu}}\ensuremath{-}{L}_{\ensuremath{\tau}}$ model including three right-handed singlet fermions and a scalar doublet to explain the anomalous magnetic moments of muon and electron simultaneously. The presence of an in-built ${Z}_{2}$ symmetry under which the right-handed singlet fermions and $\ensuremath{\eta}$ are odd, gives rise to a stable dark matter candidate along with light neutrino mass in a scotogenic fashion. In spite of the possibility of having positive and negative contributions to muon and electron ($g\ensuremath{-}2$) respectively from vector boson and charged scalar loops, the minimal scotogenic ${L}_{\ensuremath{\mu}}\ensuremath{-}{L}_{\ensuremath{\tau}}$ model cannot explain both muon and electron ($g\ensuremath{-}2$) simultaneously while being consistent with other experimental bounds. We then extend the model with a vectorlike lepton doublet which not only leads to a chirally enhanced negative contribution to electron ($g\ensuremath{-}2$) but also leads to the popular singlet-doublet fermion dark matter scenario. With this extension, the model can explain both electron and muon ($g\ensuremath{-}2$) while being consistent with neutrino mass, dark matter and other direct search bounds. The model remains predictive at high energy experiments like collider as well as low energy experiments looking for charged lepton flavor violation, dark photon searches, in addition to future ($g\ensuremath{-}2$) measurements.
31 citations
References
More filters
TL;DR: In this article, the authors present a cosmological analysis based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation.
Abstract: This paper presents cosmological results based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation. Our results are in very good agreement with the 2013 analysis of the Planck nominal-mission temperature data, but with increased precision. The temperature and polarization power spectra are consistent with the standard spatially-flat 6-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations (denoted “base ΛCDM” in this paper). From the Planck temperature data combined with Planck lensing, for this cosmology we find a Hubble constant, H0 = (67.8 ± 0.9) km s-1Mpc-1, a matter density parameter Ωm = 0.308 ± 0.012, and a tilted scalar spectral index with ns = 0.968 ± 0.006, consistent with the 2013 analysis. Note that in this abstract we quote 68% confidence limits on measured parameters and 95% upper limits on other parameters. We present the first results of polarization measurements with the Low Frequency Instrument at large angular scales. Combined with the Planck temperature and lensing data, these measurements give a reionization optical depth of τ = 0.066 ± 0.016, corresponding to a reionization redshift of . These results are consistent with those from WMAP polarization measurements cleaned for dust emission using 353-GHz polarization maps from the High Frequency Instrument. We find no evidence for any departure from base ΛCDM in the neutrino sector of the theory; for example, combining Planck observations with other astrophysical data we find Neff = 3.15 ± 0.23 for the effective number of relativistic degrees of freedom, consistent with the value Neff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to ∑ mν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero, with | ΩK | < 0.005. Adding a tensor component as a single-parameter extension to base ΛCDM we find an upper limit on the tensor-to-scalar ratio of r0.002< 0.11, consistent with the Planck 2013 results and consistent with the B-mode polarization constraints from a joint analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP B-mode data to our analysis leads to a tighter constraint of r0.002 < 0.09 and disfavours inflationarymodels with a V(φ) ∝ φ2 potential. The addition of Planck polarization data leads to strong constraints on deviations from a purely adiabatic spectrum of fluctuations. We find no evidence for any contribution from isocurvature perturbations or from cosmic defects. Combining Planck data with other astrophysical data, including Type Ia supernovae, the equation of state of dark energy is constrained to w = −1.006 ± 0.045, consistent with the expected value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundances for the best-fit Planck base ΛCDM cosmology are in excellent agreement with observations. We also constraints on annihilating dark matter and on possible deviations from the standard recombination history. In neither case do we find no evidence for new physics. The Planck results for base ΛCDM are in good agreement with baryon acoustic oscillation data and with the JLA sample of Type Ia supernovae. However, as in the 2013 analysis, the amplitude of the fluctuation spectrum is found to be higher than inferred from some analyses of rich cluster counts and weak gravitational lensing. We show that these tensions cannot easily be resolved with simple modifications of the base ΛCDM cosmology. Apart from these tensions, the base ΛCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.
10,728 citations
TL;DR: In this paper, the authors present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB, which are consistent with the six-parameter inflationary LCDM cosmology.
Abstract: We present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB. These data are consistent with the six-parameter inflationary LCDM cosmology. From the Planck temperature and lensing data, for this cosmology we find a Hubble constant, H0= (67.8 +/- 0.9) km/s/Mpc, a matter density parameter Omega_m = 0.308 +/- 0.012 and a scalar spectral index with n_s = 0.968 +/- 0.006. (We quote 68% errors on measured parameters and 95% limits on other parameters.) Combined with Planck temperature and lensing data, Planck LFI polarization measurements lead to a reionization optical depth of tau = 0.066 +/- 0.016. Combining Planck with other astrophysical data we find N_ eff = 3.15 +/- 0.23 for the effective number of relativistic degrees of freedom and the sum of neutrino masses is constrained to < 0.23 eV. Spatial curvature is found to be |Omega_K| < 0.005. For LCDM we find a limit on the tensor-to-scalar ratio of r <0.11 consistent with the B-mode constraints from an analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP data leads to a tighter constraint of r < 0.09. We find no evidence for isocurvature perturbations or cosmic defects. The equation of state of dark energy is constrained to w = -1.006 +/- 0.045. Standard big bang nucleosynthesis predictions for the Planck LCDM cosmology are in excellent agreement with observations. We investigate annihilating dark matter and deviations from standard recombination, finding no evidence for new physics. The Planck results for base LCDM are in agreement with BAO data and with the JLA SNe sample. However the amplitude of the fluctuations is found to be higher than inferred from rich cluster counts and weak gravitational lensing. Apart from these tensions, the base LCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.
9,745 citations
TL;DR: The review as discussed by the authors summarizes much of particle physics and cosmology using data from previous editions, plus 3,283 new measurements from 899 Japers, including the recently discovered Higgs boson, leptons, quarks, mesons and baryons.
Abstract: The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 Japers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters.
7,337 citations
4,084 citations
TL;DR: The experimental limits placed on the oblique correction parameters S and T are reviewed and the value of S can be estimated for running and walking technicolor theories are discussed.
Abstract: I will first review the experimental limits placed on the oblique correction parameters S and T. Then, I will discuss how the value of S can be estimated for running and walking technicolor theories.
2,020 citations