137 citations · 2.1k across the 138 of their papers we have counts for
95 papers · 1 filter
Kaluza--Klein Dark-Photon Mediation of Inelastic Dark Matter at LUX-ZEPLIN
Waqas Ahmed, George K. Leontaris
We study a five-dimensional realization of endothermic dark matter motivated by the recent high-recoil LUX-ZEPLIN event. A pseudo-Dirac Standard-Model singlet fermion is localized…
A Dark-Dimension Origin of Geometric Inelastic Dark Matter: The LUX-ZEPLIN High-Recoil Event and Multi-Target Tests
Waqas Ahmed, George K. Leontaris
The extended nuclear-recoil analysis of LUX-ZEPLIN (LZ) has reported one event compatible with a recoil energy near keV, motivating endothermic dark-matter scenarios with sup…
Secondary Gravitational Wave Signatures from 5D Rotating Primordial Black Holes in the Dark Dimension
Waqas Ahmed, George K. Leontaris
We investigate five-dimensional rotating primordial black holes (PBHs) as dark matter candidates within the Dark Dimension (DD) scenario motivated by the Swampland Program. In this…
Micron-sized Extra Dimensions and Primordial Black Holes: Charged, Rotating, and Memory Burdened
George K. Leontaris, George Prampromis
We explore the possibility of explaining dark matter through six-dimensional (6D) primordial black holes (PBHs) in a theory with two extra dimensions. Interestingly, in this scenar…
On the phenomenological implications of a Pati-Salam model spontaneously broken by Higgs fields in fundamental representations
George K. Leontaris, Ruiwen Ouyang, Ye-ling Zhou
We present a supersymmetric Pati-Salam model with small representations as a potential candidate for physics beyond the Standard Model. The model features a Higgs sector with bifun…
Modular Family Symmetry in Fluxed GUTs
Vasileios Basiouris, Miguel Crispim Romão, Stephen F. King +1
We discuss modular family symmetry in effective theories based on generic properties of bottom-up local F-theory inspired GUTs broken by fluxes, which we refer to as Fluxed GUTs. W…
Leptogenesis in Realistic Flipped SU(5)
Stephen F. King, George K. Leontaris, Luca Marsili +1
We study thermal leptogenesis in realistic supersymmetric flipped unification. As up-type quarks and neutrinos are arranged in the same multiplets, they exhibit…
Flipped SU(5): unification, proton decay, fermion masses and gravitational waves
Stephen F. King, George K. Leontaris, Ye-Ling Zhou
We study supersymmetric (SUSY) flipped unification, focussing on its predictions for proton decay, fermion masses and gravitational waves. We performed a two-loo…
Hybrid Inflation, Reheating and Dark Radiation in a IIB perturbative moduli stabilization scenario
Waqas Ahmed, Athanasios Karozas, George K. Leontaris +1
We study the cosmological implications of an effective field theory model derived within a configuration of D7 brane stacks in the framework of type-IIB string theory. We consider…
Sterile neutrinos, decay and the W-boson mass anomaly in a Flipped from F-theory
Vasileios Basiouris, George K. Leontaris
We investigate the low energy properties of an effective local model with flipped gauge group, constructed within the framework of F-theory. Its origin is trac…
Smooth Hybrid Inflation with Low Reheat Temperature and Observable Gravity Waves in Super-GUT
Waqas Ahmed, Athanasios Karozas, George K. Leontaris +1
We realize smooth hybrid inflation in the framework of supersymmetric model which provides a natural solution to the monopole problem appearing…
Flipped SU(5) with modular symmetry
Georgianna Charalampous, Stephen F. King, George K. Leontaris +1
We study Flipped Grand Unified Theories (GUTs) with modular symmetry. We propose two models with different modular weights assignments, where the…
models with a vector-like fermion family
A. Karozas, G. K. Leontaris, I. Tavellaris
Motivated by experimental measurements indicating deviations from the Standard Model predictions we discuss F-theory inspired models, which, in addition to the three chiral generat…
Gravitino Dark matter, Non Thermal Leptogenesis and Low reheating temperature in No-scale Higgs Inflation
Waqas Ahmed, Athanasios Karozas, George K. Leontaris
We revisit Higgs inflation in the framework of a minimal extension of the Standard Model gauge symmetry by a factor. Various aspects are taken into account with partic…
Low Scale String Theory Benchmarks for Hidden Photon Dark Matter Interpretations of the XENON1T Anomaly
Athanasios Karozas, Stephen F. King, George K. Leontaris +1
An excess of low-energy electronic recoil events over known backgrounds was recently observed in the XENON1T detector, where events are observed compared to an expected $232…
On the LHC signatures of F-theory motivated models
A. Karozas, G. K. Leontaris, I. Tavellaris +1
We study low energy implications of F-theory GUT models based on extended by a symmetry which couples non-universally to the three families of quarks and leptons. T…
Light Sterile Neutrino and Low Scale Left-Right Symmetry in D-brane inspired
George K. Leontaris, Qaisar Shafi
Motivated by the ongoing searches for new physics at the LHC, we explore the low energy consequences of a D-brane inspired (4-2-2) model. Th…
- oscillations and the neutron lifetime
George K. Leontaris, John D. Vergados
Neutron-antineutron oscillations are considered in the light of recently proposed particle models, which claim to resolve the neutron lifetime anomaly, indicating the existence of…
New Physics Phenomena and F-theory GUTs
George K. Leontaris
In this presentation the new physics implications of the -meson decay anomalies, observed at LHCb, are discussed. In the first part of the talk a brief overview of the experimen…
Non-universal from Fluxed GUTs
Miguel Crispim Romao, Stephen F. King, George K. Leontaris
We make a first systematic study of non-universal TeV scale neutral gauge bosons arising naturally from a class of F-theory inspired models broken via by flux. The phe…
Vectorlike Particles, and Yukawa Unification in F-theory inspired
Athanasios Karozas, George K. Leontaris, Qaisar Shafi
We explore the low energy implications of an F-theory inspired model whose breaking yields, in addition to the MSSM gauge symmetry, a gauge boson associated with a $U(1)…
Magnetic Monopoles and Free Fractionally Charged States at Accelerators and in Cosmic Rays
Thomas W. Kephart, George K. Leontaris, Qaisar Shafi
Unified theories of strong, weak and electromagnetic interactions which have electric charge quantization predict the existence of topologically stable magnetic monopoles. Intermed…
Phenomenology with F-theory SU(5)
George K. Leontaris, Qaisar Shafi
We explore the low energy phenomenology of an F-theory based SU(5) model which, in addition to the known quarks and leptons, contains Standard Model singlets, and vector-like color…
PSL(2,7) Representations and their relevance to Neutrino Physics
G. Aliferis, G. K. Leontaris, N. D. Vlachos
The investigation of the role of finite groups in flavor physics and particularly, in the interpretation of the neutrino data has been the subject of intensive research. Motivated…