Light dark matter from inflaton decay

Abstract We propose a simple mechanism of light dark matter (DM) production from the decay of the oscillating inflaton condensation. If the reheating temperature after inflation is higher than the inflaton mass, which is of the same order of the momentum of the DM at the time of the production, the DM momentum can be suppressed compared to the temperature of the thermal plasma if the interaction of the DM is weak enough. Consequently, the DM can be cold enough to avoid the observational constraints on the warm DM, like the Lyman-α bound even if the DM mass is small. We study the bosonic and fermionic DM production from the inflaton decay, taking into account the effect of the stimulated emission and Pauli blocking, respectively. In both cases, the DM can be cold and abundant enough to be a viable candidate of the DM. We also apply our mechanism to the production of isocurvature-problem-free axion DM and Dirac sea DM of right-handed neutrino consistent the seesaw relation for the active neutrino masses.

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Heavy right-handed neutrino dark matter in left–right models

Modern Physics Letters A ◽

10.1142/s0217732317400077 ◽

2017 ◽

Vol 32 (15) ◽

pp. 1740007 ◽

Cited By ~ 15

Author(s):

P. S. Bhupal Dev ◽

Rabindra N. Mohapatra ◽

Yongchao Zhang

Keyword(s):

Dark Matter ◽

Mass Range ◽

Neutrino Masses ◽

Seesaw Mechanism ◽

Leptonic Sector ◽

Active Neutrino ◽

The Standard Model ◽

The Stability ◽

The Universe

We show that in a class of non-supersymmetric left–right extensions of the Standard Model (SM), the lightest right-handed neutrino (RHN) can play the role of thermal Dark Matter (DM) in the Universe for a wide mass range from TeV to PeV. Our model is based on the gauge group [Formula: see text] in which a heavy copy of the SM fermions is introduced and the stability of the RHN DM is guaranteed by an automatic [Formula: see text] symmetry present in the leptonic sector. In such models, the active neutrino masses are obtained via the type-II seesaw mechanism. We find a lower bound on the RHN DM mass of order TeV from relic density constraints, as well as a unitarity upper bound in the multi-TeV to PeV scale, depending on the entropy dilution factor. The RHN DM could be made long-lived by soft-breaking of the [Formula: see text] symmetry and provides a concrete example of decaying DM interpretation of the PeV neutrinos observed at IceCube.

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Current and future neutrino oscillation constraints on leptonic unitarity

Journal of High Energy Physics ◽

10.1007/jhep12(2020)068 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

Sebastian A. R. Ellis ◽

Kevin J. Kelly ◽

Shirley Weishi Li

Keyword(s):

Precise Measurement ◽

Sterile Neutrino ◽

Current Knowledge ◽

Unknown Origin ◽

Neutrino Masses ◽

Matrix Elements ◽

Neutrino Mixing ◽

Next Generation ◽

Active Neutrino ◽

Mixing Matrix

Abstract The unitarity of the lepton mixing matrix is a critical assumption underlying the standard neutrino-mixing paradigm. However, many models seeking to explain the as-yet-unknown origin of neutrino masses predict deviations from unitarity in the mixing of the active neutrino states. Motivated by the prospect that future experiments may provide a precise measurement of the lepton mixing matrix, we revisit current constraints on unitarity violation from oscillation measurements and project how next-generation experiments will improve our current knowledge. With the next-generation data, the normalizations of all rows and columns of the lepton mixing matrix will be constrained to ≲10% precision, with the e-row best measured at ≲1% and the τ-row worst measured at ∼10% precision. The measurements of the mixing matrix elements themselves will be improved on average by a factor of 3. We highlight the complementarity of DUNE, T2HK, JUNO, and IceCube Upgrade for these improvements, as well as the importance of ντ appearance measurements and sterile neutrino searches for tests of leptonic unitarity.

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Dark matter candidates in a type-II radiative neutrino mass model

Journal of High Energy Physics ◽

10.1007/jhep06(2021)072 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Roberto A. Lineros ◽

Mathias Pierre

Keyword(s):

Dark Matter ◽

Neutral Particle ◽

Matter Density ◽

Indirect Detection ◽

Dark Matter Candidate ◽

Neutrino Masses ◽

Type Ii ◽

Mass Model ◽

Direct And Indirect Detection

Abstract We explore the connection between Dark Matter and neutrinos in a model inspired by radiative Type-II seessaw and scotogenic scenarios. In our model, we introduce new electroweakly charged states (scalars and a vector-like fermion) and impose a discrete ℤ2 symmetry. Neutrino masses are generated at the loop level and the lightest ℤ2-odd neutral particle is stable and it can play the role of a Dark Matter candidate. We perform a numerical analysis of the model showing that neutrino masses and flavour structure can be reproduced in addition to the correct dark matter density, with viable DM masses from 700 GeV to 30 TeV. We explore direct and indirect detection signatures and show interesting detection prospects by CTA, Darwin and KM3Net and highlight the complementarity between these observables.

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Minimal scoto-seesaw mechanism with spontaneous CP violation

Journal of High Energy Physics ◽

10.1007/jhep04(2021)249 ◽

2021 ◽

Vol 2021 (4) ◽

Author(s):

D. M. Barreiros ◽

F. R. Joaquim ◽

R. Srivastava ◽

J. W. F. Valle

Keyword(s):

Dark Matter ◽

Cp Violation ◽

Vacuum Expectation ◽

Vacuum Expectation Value ◽

Discrete Symmetry ◽

Double Beta Decay ◽

Neutrino Masses ◽

Seesaw Mechanism ◽

Cosmological Observations ◽

Scalar Singlet

Abstract We propose simple scoto-seesaw models to account for dark matter and neutrino masses with spontaneous CP violation. This is achieved with a single horizontal $$ {\mathcal{Z}}_8 $$ Z 8 discrete symmetry, broken to a residual $$ {\mathcal{Z}}_2 $$ Z 2 subgroup responsible for stabilizing dark matter. CP is broken spontaneously via the complex vacuum expectation value of a scalar singlet, inducing leptonic CP-violating effects. We find that the imposed $$ {\mathcal{Z}}_8 $$ Z 8 symmetry pushes the values of the Dirac CP phase and the lightest neutrino mass to ranges already probed by ongoing experiments, so that normal-ordered neutrino masses can be cornered by cosmological observations and neutrinoless double beta decay experiments.

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INTERACTION BETWEEN DARK ENERGY AND DARK MATTER: OBSERVATIONAL CONSTRAINTS FROM OHD, BAO, CMB AND SNe Ia

International Journal of Modern Physics D ◽

10.1142/s021827181350082x ◽

2013 ◽

Vol 22 (14) ◽

pp. 1350082 ◽

Cited By ~ 26

Author(s):

SHUO CAO ◽

NAN LIANG

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Observational Constraints ◽

Coincidence Problem ◽

Cosmological Constraints ◽

Coincidence Index ◽

Acceleration Of The Universe ◽

Interaction Term ◽

Negative Coupling ◽

The Universe

In order to test if there is energy transfer between dark energy (DE) and dark matter (DM), we investigate cosmological constraints on two forms of nontrivial interaction between the DM sector and the sector responsible for the acceleration of the universe, in light of the newly revised observations including OHD, CMB, BAO and SNe Ia. More precisely, we find the same tendencies for both phenomenological forms of the interaction term Q = 3γHρ, i.e. the parameter γ to be a small number, |γ| ≈ 10-2. However, concerning the sign of the interaction parameter, we observe that γ > 0 when the interaction between dark sectors is proportional to the energy density of dust matter, whereas the negative coupling (γ < 0) is preferred by observations when the interaction term is proportional to DE density. We further discuss two possible explanations to this incompatibility and apply a quantitative criteria to judge the severity of the coincidence problem. Results suggest that the γm IDE model with a positive coupling may alleviate the coincidence problem, since its coincidence index C is smaller than that for the γd IDE model, the interacting quintessence and phantom models by four orders of magnitude.

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THE DARK-MATTER WORLD: ARE THERE DARK-MATTER GALAXIES?

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512005703 ◽

2012 ◽

Vol 10 ◽

pp. 1-12

Author(s):

W-Y. PAUCHY HWANG

Keyword(s):

Dark Matter ◽

Time Span ◽

Neutrino Masses ◽

Ordinary Matter ◽

Cosmic Neutrino Background ◽

Cosmic Neutrino ◽

Neutrino Background

We attempt to answer whether neutrinos and antineutrinos, such as those in the cosmic neutrino background, would clusterize among themselves or even with other dark-matter particles, under certain time span, say 1 Gyr. With neutrino masses in place, the similarity with the ordinary matter increases and so is our confidence for neutrino clustering if time is long enough. In particular, the clusterings could happen with some seeds (cf. see the text for definition), the chance in the dark-matter world to form dark-matter galaxies increases. If the dark-matter galaxies would exist in a time span of 1 Gyr, then they might even dictate the formation of the ordinary galaxies (i.e. the dark-matter galaxies get formed first); thus, the implications for the structure of our Universe would be tremendous.

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