Dark matter in the fully flipped 3-3-1-1 model Van Loi, Duong; Nam, Cao H.; Van Dong, Phung
The European physical journal. C, Particles and fields,
07/2021, Volume:
81, Issue:
7
Journal Article
Peer reviewed
Open access
We present the features of the fully flipped 3-3-1-1 model and show that this model leads to dark matter candidates naturally. We study two dark matter scenarios corresponding to the triplet fermion ...and singlet scalar candidates, and we determine the viable parameter regimes constrained from the observed relic density and direct detection experiments.
We demonstrate straightforward fabrication of highly sensitive biosensor arrays based on field-effect transistors, using an efficient high-throughput, large-area patterning process. Chemical lift-off ...lithography is used to construct field-effect transistor arrays with high spatial precision suitable for the fabrication of both micrometer- and nanometer-scale devices. Sol–gel processing is used to deposit ultrathin (∼4 nm) In2O3 films as semiconducting channel layers. The aqueous sol–gel process produces uniform In2O3 coatings with thicknesses of a few nanometers over large areas through simple spin-coating, and only low-temperature thermal annealing of the coatings is required. The ultrathin In2O3 enables construction of highly sensitive and selective biosensors through immobilization of specific aptamers to the channel surface; the ability to detect subnanomolar concentrations of dopamine is demonstrated.
The subfamily of the Lemnoideae belongs to a different order than other monocotyledonous species that have been sequenced and comprises aquatic plants that grow rapidly on the water surface. Here we ...select Spirodela polyrhiza for whole-genome sequencing. We show that Spirodela has a genome with no signs of recent retrotranspositions but signatures of two ancient whole-genome duplications, possibly 95 million years ago (mya), older than those in Arabidopsis and rice. Its genome has only 19,623 predicted protein-coding genes, which is 28% less than the dicotyledonous Arabidopsis thaliana and 50% less than monocotyledonous rice. We propose that at least in part, the neotenous reduction of these aquatic plants is based on readjusted copy numbers of promoters and repressors of the juvenile-to-adult transition. The Spirodela genome, along with its unique biology and physiology, will stimulate new insights into environmental adaptation, ecology, evolution and plant development, and will be instrumental for future bioenergy applications.
A
bstract
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.
Artificial neural network is a powerful tool in the forecast of solar irradiance. In order to gain higher forecasting accuracy, artificial neural network and wavelet analysis have been combined to ...develop a new method of the forecast of solar irradiance. In this paper, the data sequence of solar irradiance as samples is mapped into several time-frequency domains using wavelet transformation, and a recurrent back-propagation (BP) network is established for each domain. The solar irradiance forecasted equals the algebraic sum of the components, which were predicted correspondingly by the established networks, of all the time-frequency domains. A discount coefficient method is adopted in updating the weights and biases of the networks so that the late forecasts play more important roles. On the basis of the principle of combination of artificial neural networks and wavelet analysis, a model is completed for fore-casting solar irradiance. Based on the historical day-by-day records of solar irradiance in Shanghai an example of forecasting total irradiance is presented. The results of the example indicate that the method makes the forecasts much more accurate than the forecasts using the artificial neural networks without combination with wavelet analysis.
We numerically study the thermoelectric transport properties in bilayer phosphorene in the presence of bias voltage under a strong magnetic field. When a bias voltage is applied and the bulk energy ...gap is closed, it is found that thermoelectric coefficients has similar properties to those of a semimetal. Around the central Landau Level (LL), the transverse thermoelectric conductivity displays a series of peaks, but the longitudinal thermoelectric conductivity oscillates and changes sign. The Nernst signal has a peak at central LL and changes sign near other LLs, while the thermopower has an opposite behavior. Both the thermoelectric conductivities and Nernst signal exhibit remarkable anisotropy, but thermopower exhibits isotropy.
In this paper, we have studied how the presence of massive gravity modifies the Joule–Thomson expansion of the charged AdS black hole. We showed that the graviton mass and the coupling parameters ...affect the constant mass curve, the Joule–Thomson coefficient, and the inversion curve on a significant level. For the graviton mass or the coupling parameters at/above certain values, the Joule–Thomson expansion of the black hole with given mass and charge is only possible to lead to the heating without leading to the cooling. In addition, massive gravity can make the heating and cooling in the Joule–Thomson expansion of the black hole happen faster or slower, depending on the sign of the coupling parameters. Furthermore, the lower value of the inversion temperature can appear at the nonzero pressure.
Abstract
A pseudospin-1/2 Mott phase on a honeycomb lattice is proposed to host the celebrated two-dimensional Kitaev model which has an elusive quantum spin liquid ground state, and fascinating ...physics relevant to the development of future templates towards topological quantum bits. Here we report a comprehensive, atomically resolved real-space study by scanning transmission electron and scanning tunnelling microscopies on a novel layered material displaying Kitaev physics, α-RuCl
3
. Our local crystallography analysis reveals considerable variations in the geometry of the ligand sublattice in thin films of α-RuCl
3
that opens a way to realization of a spatially inhomogeneous magnetic ground state at the nanometre length scale. Using scanning tunnelling techniques, we observe the electronic energy gap of ≈0.25 eV and intra-unit cell symmetry breaking of charge distribution in individual α-RuCl
3
surface layer. The corresponding charge-ordered pattern has a fine structure associated with two different types of charge disproportionation at Cl-terminated surface.
The optoelectronic properties of hybrid perovskites can be easily tailored by varying their components. Specifically, mixing the common short organic cation (methylammonium (MA)) with a larger one ...(e.g., butyl ammonium (BA)) results in 2-dimensional perovskites with varying thicknesses of inorganic layers separated by the large organic cation. In both of these applications, a detailed understanding of the dissociation and recombination of electron–hole pairs is of prime importance. In this work, we give a clear experimental demonstration of the interconversion between bound excitons and free charges as a function of temperature by combining microwave conductivity techniques with photoluminescence measurements. We demonstrate that the exciton binding energy varies strongly (between 80 and 370 meV) with the thickness of the inorganic layers. Additionally, we show that the mobility of charges increases with the layer thickness, in agreement with calculated effective masses from electronic structure calculations.
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