54 citations · 271 across the 16 of their papers we have counts for
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Varying Entropy Degrees of Freedom Effects in Low-Scale Leptogenesis
Dimitrios Karamitros, Thomas McKelvey, Apostolos Pilaftsis
We analyse in detail the effect of varying entropy degrees of freedom on low-scale leptogenesis models. As an archetypal model, we consider the Tri-Resonant Leptogensis (TRL) s…
Freeze-in baryogenesis and early matter domination
Ioannis Dalianis, Andreas Goudelis, Dimitrios Karamitros +2
The freeze-in mechanism has been shown to allow the simultaneous generation of cosmic dark matter and a viable matter-antimatter asymmetry in the universe. When the underlying inte…
Quantum Coherence of Critical Unstable Two-Level Systems
Dimitrios Karamitros, Thomas McKelvey, Apostolos Pilaftsis
We study in detail the dynamics of unstable two-level quantum systems by adopting the Bloch-sphere formalism of qubits. By employing the Bloch-vector representation for such unstab…
Tri-Resonant Leptogenesis in a Seesaw Extension of the Standard Model
P. Candia da Silva, D. Karamitros, T. McKelvey +1
We study a class of leptogenesis models where the light neutrinos acquire their observed small masses by a symmetry-motivated construction. This class of models may naturally inclu…
Ultraviolet freeze-in baryogenesis
Andreas Goudelis, Dimitrios Karamitros, Pantelis Papachristou +1
We study a mechanism through which the cosmic dark matter density can be explained simultaneously with the observed baryon asymmetry of the Universe. At the core of our proposal li…
MiMeS, the Misalignment Mechanism Solver
Dimitrios Karamitros
We briefly discuss MiMeS, a C++ library that can solve the axion and axion-like equation of motion in various axion models and cosmological histories.
New opportunities for axion dark matter searches in nonstandard cosmological models
Paola Arias, Nicolás Bernal, Dimitrios Karamitros +3
We study axion dark matter production from a misalignment mechanism in scenarios featuring a general nonstandard cosmology. Before the onset of Big Bang nucleosynthesis, the energy…
Frozen-in fermionic singlet dark matter in non-standard cosmology with a decaying fluid
Paola Arias, Dimitrios Karamitros, Leszek Roszkowski
We perform a detailed study of dark matter production via freeze-in under the assumption that some fluid dominates the early Universe before depositing its energy to the plasma cau…
Forbidden Freeze-In
Luc Darmé, Andrzej Hryczuk, Dimitrios Karamitros +1
We study the importance of a frozen-in dark matter production regime, where the dark matter particle is produced via kinematically forbidden decays that arise from significant ther…
Neutrino dark matter and the Higgs portal: improved freeze-in analysis
Valentina De Romeri, Dimitrios Karamitros, Oleg Lebedev +1
Sterile neutrinos are one of the leading dark matter candidates. Their masses may originate from a vacuum expectation value of a scalar field. If the sterile neutrino couplings are…
Forbidden frozen-in dark matter
Luc Darmé, Andrzej Hryczuk, Dimitrios Karamitros +1
We examine and point out the importance of a regime of dark matter production through the freeze-in mechanism that results from a large thermal correction to a decaying mediator pa…
Pseudo Nambu-Goldstone Dark Matter: Examples of Vanishing Direct Detection Cross Section
Dimitrios Karamitros
We consider cases where the dark matter-nucleon interaction is naturally suppressed. We explicitly show that by extending the standard model scalar sector by a number of singlets,…
Radiative Light Dark Matter
Athanasios Dedes, Dimitrios Karamitros, Apostolos Pilaftsis
We present a Peccei-Quinn (PQ)-symmetric two-Higgs doublet model that naturally predicts a fermionic singlet dark matter in the mass range 10 keV-1 GeV. The origin of the smallness…
A Fermionic bi-Doublet Effective Field Theory for Dark Matter
Dimitrios Karamitros
We study an effective field theory which includes the Standard Model extended by a Dark Sector consisting of two fermionic -doublets. A parity guarantees that, aft…
Effective Theory for Electroweak Doublet Dark Matter
Athanasios Dedes, Dimitrios Karamitros, Vassilis C. Spanos
We perform a detailed study of an effective field theory which includes the Standard Model particle content extended by a pair of Weyl fermionic SU(2)-doublets with opposite hyperc…
Doublet-Triplet Fermionic Dark Matter
Athanasios Dedes, Dimitrios Karamitros
We extend the Standard Model (SM) by adding a pair of fermionic SU(2)-doublets with opposite hypercharge and a fermionic SU(2)-triplet with zero hypercharge. We impose a discrete Z…