arXiv subjects
Publications and source records attributed to Ariel Arza.
We study a model where photons interact with hidden photons and millicharged particles through a kinetic mixing term. Particularly, we focus in vacuum birefringence effects and we find a bound for the millicharged parameter assuming that hidden photons are a piece of the local dark matter density
Vacuum magnetic birefringence is one of the most interesting non-linear phenomena in quantum electrodynamics because it is a pure photon-photon result of the theory and it directly signalizes the violation of the classical superposition principle of electromagnetic fields in the full quantum theory. We perform analytical and numerical calculations when an electromagnetic wave interacts with an oscillating external magnetic field. We find that in an ideal cavity, when the external field frequency is around the electromagnetic wave frequency, the normal and parallel components of the wave suffer parametric resonance at different rates, producing a vacuum birefringence effect growing in time. We also study the case where there is no cavity and the oscillating magnetic field is spatially localized in a region of length $L$. In both cases we find also a rotation of the elliptical axis.
We study a Light Shinning Through the wall type setup with microwave cavities, where the regeneration cavity has a moving boundary condition oscillating harmonically. We find a parametric resonance that could enhance the probability conversion between Weakly Interacting Slim Particles and photons by several orders of magnitude.
A variant of quantum electrodynamics coupled to a dark photon through a kinetic mixing is studied. The analogous of the light-light diagram becomes the conversion process $γ'γ' \to γγ$ and an expression for the differential cross section is estimated. For high energies beams, as in LHC, this differential cross section could be measurable and its magnitude would be typically similar to the total cross section of neutrinos, {\it i.e.} $\sim 10^{-50}\,{\text{m}}^2$.
We study the local effects of an external time-dependent magnetic field on axion-like particles assuming they are all the dark matter of the universe. We find that under suitable conditions the amplitude of the dark matter field can resonate parametrically. The resonance depends on the velocity of the axion-like particles and scales quadratically with the strength} of the external magnetic field, $\fracρ{ρ_{DM}} \sim {B_0}^3$. By considering typical experimental benchmark values, we find the resonance could amplify around two orders of magnitude the local energy density stored in the dark matter condensate.
We point out that a cold dark matter condensate made of gauge bosons from an extra hidden U(1) sector - dubbed hidden- photons - can create a small, oscillating electric density current. Thus, they could also be searched for in the recently proposed LC-circuit setup conceived for axion cold dark matter search by Sikivie, Sullivan and Tanner. We estimate the sensitivity of this setup for hidden-photon cold dark matter and we find it could cover a sizable, so far unexplored parameter space.