Publications (14)
Light from darkness: history of a hot dark sector
Rupert Coy, Jean Kimus, Michel H. G. Tytgat
We study a scenario in which the expansion of the Early Universe is driven by a hot hidden sector (HS) with an initial temperature that is significantly higher than that of th…
Dynamical Clockwork Axions
Rupert Coy, Michele Frigerio, Masahiro Ibe
The clockwork mechanism is a novel method for generating a large separation between the dynamical scale and interaction scale of a theory. We demonstrate how the mechanism can aris…
The domain of thermal dark matter candidates
Rupert Coy, Thomas Hambye, Michel H. G. Tytgat +1
We consider, in general terms, the possible parameter space of thermal dark matter candidates. We assume that the dark matter particle is fundamental and was in thermal equilibrium…
Neutrino forces and the Sommerfeld enhancement
Rupert Coy, Xun-Jie Xu, Bingrong Yu
The Sommerfeld enhancement plays an important role in dark matter (DM) physics, and can significantly enhance the annihilation cross section of non-relativistic DM particles. In th…
Probing the muon with future beam dump experiments
Rupert Coy, Xun-Jie Xu
We consider the light explanation of the muon anomaly. Even if such a has no tree-level coupling to electrons, in general one will be induced at loop-level. We show…
A forgotten fermion: the hypercharge -3/2 doublet, its phenomenology and connections to dark matter
Rupert Coy
A weak-doublet with hypercharge is one of only a handful of fermions which has a renormalisable interaction with Standard Model fields. This should make it worthy of attenti…
A closer look at the seesaw-dark matter correspondence
Rupert Coy, Aritra Gupta
In an earlier work, we showed that in very simple neutrino portal-like extensions of the Standard Model it is possible to achieve a one-to-one correspondence between dark matter ph…
New physics in transitions at one loop
Rupert Coy, Michele Frigerio, Federico Mescia +1
We investigate new-physics contributions to transitions in the context of an effective field theory extension of the Standard Model, including operator mixing at…
Effective comparison of neutrino-mass models
Rupert Coy, Michele Frigerio
New physics in the lepton sector may account for neutrino masses, affect electroweak precision observables, induce charged-lepton flavour violation, and shift dipole moments. The l…
Solving the electron and muon anomalies in models
Arushi Bodas, Rupert Coy, Simon J. D. King
We consider simultaneous explanations of the electron and muon anomalies through a single of a extension to the Standard Model (SM). We first perform a model-ind…
Effective approach to lepton observables: the seesaw case
Rupert Coy, Michele Frigerio
In the absence of direct evidence of new physics, any ultraviolet theory can be reduced to its specific set of low-energy effective operators. As a case study, we derive the effect…
Neutrino lines from DM decay induced by high-scale seesaw interactions
Rupert Coy, Thomas Hambye
If the stability of the dark matter (DM) particle is due to an accidental symmetry, nothing prevents UV physics from destabilising it by inducing DM decays suppressed by powers of…
Freeze-in and freeze-out of sterile neutrino dark matter
Rupert Coy, Michael A. Schmidt
A sterile neutrino with a keV-scale mass is a compelling dark matter candidate. We propose a new production mechanism involving the decay and annihilation of a complex scalar singl…
Seesaw determination of the dark matter relic density
Rupert Coy, Aritra Gupta, Thomas Hambye
In this article, we show that in the usual type-I seesaw framework, augmented solely by a neutrino portal interaction, the dark matter (DM) relic density can be created through fre…