Results 11 to 20 of about 132 (62)
Scalar-singlet assisted leptogenesis with CP violation from the vacuum
Journal of High Energy Physics, 2023 In the vanilla type-I seesaw leptogenesis scenario, CP violation required to generate the lepton asymmetries in the heavy Majorana neutrino decays stem from complex Dirac-type Yukawa couplings. In this paper we explore the case in which that CP violation
D. M. Barreiros +3 more
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Leptonic CP asymmetry and Light flavored scalar
Journal of High Energy Physics, 2023 We consider a situation where right-handed neutrinos couple to a light scalar which is possibly a Nambu-Goldstone boson resulting from high-energy symmetry breaking. Its coupling is typically complex-valued and flavor-dependent.
Yoshihiko Abe +2 more
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The Exact WKB analysis for asymmetric scalar preheating
Journal of High Energy Physics, 2023 Using the exact WKB analysis of the higher-order differential equations, we analyze the asymmetry in dynamical particle production of a complex scalar field. The solution requires the Stokes phenomena of the fourth-order differential equation.
Seishi Enomoto, Tomohiro Matsuda
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Journal of High Energy Physics, 2023 Ultra-low mass primordial black holes (PBH), which may briefly dominate the energy density of the universe but completely evaporate before the big bang nucleosynthesis (BBN), can lead to interesting observable signatures. In our previous work, we studied
Nilanjandev Bhaumik +3 more
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The scalar singlet extension of the Standard Model: gravitational waves versus baryogenesis
Journal of High Energy Physics, 2023 We study the possible gravitational wave signal and the viability of baryogenesis arising from the electroweak phase transition in an extension of the Standard Model (SM) by a scalar singlet field without a ℤ2 symmetry.
John Ellis +4 more
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Baryogenesis and dark matter in the mirror twin Higgs
Journal of High Energy Physics, 2023 We consider a natural asymmetric dark matter (ADM) model in the mirror twin Higgs (MTH). We show that it is possible to obtain the correct dark matter (DM) abundance when a twin baryon is the DM without the need of explicit breaking of the MTH ℤ2 ...
Pedro Bittar +2 more
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Z2 non-restoration and composite Higgs: singlet-assisted baryogenesis w/o topological defects
Journal of High Energy Physics, 2022 Simple scalar-singlet extensions of the Standard Model with a (spontaneously broken) Z 2 symmetry allow for a strong first order electroweak phase transition, as sought in order to realize electroweak baryogenesis.
Andrei Angelescu +2 more
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Leptogenesis in automatic Nelson-Barr models
Journal of High Energy PhysicsIn this study, we numerically show that automatic Nelson-Barr models with new chiral fermions can simultaneously solve the strong CP problem and generate the observed baryon asymmetry via high-scale leptogenesis.
C. Murgui, S. Patrone
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Bounds on right-handed neutrino parameters from observable leptogenesis
Journal of High Energy Physics, 2022 We revisit the generation of a matter-antimatter asymmetry in the minimal extension of the Standard Model with two singlet heavy neutral leptons (HNL) that can explain neutrino masses. We derive an accurate analytical approximation to the solution of the
P. Hernández +3 more
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Low-scale leptogenesis with flavour and CP symmetries
Journal of High Energy Physics, 2022 We consider a type-I seesaw framework endowed with a flavour symmetry, belonging to the series of non-abelian groups ∆(3 n 2) and ∆(6 n 2), and a CP symmetry.
M. Drewes +3 more
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