Related papers: Supernova Brightening from Chameleon-Photon Mixing
Scalar fields with a "chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple…
In chameleon field theories a scalar field can couple to matter with gravitational strength and still evade local gravity constraints due to a combination of self-interactions and the couplings to matter. Originally, these theories were…
Distant supernovae have been observed to be fainter than what is expected in a matter dominated universe. The most likely explanation is that the universe is dominated by an energy component with negative pressure -- dark energy. However,…
The physical origin of the dark energy that causes the accelerated expansion rate of the universe is one of the major open questions of cosmology. One set of theories postulates the existence of a self-interacting scalar field for dark…
Chameleon dark energy models are a popular alternative to the standard cosmological constant model. These models consist of a new light degree of freedom, called chameleon, with a density dependent mass and a non-trivial coupling to both…
Composite supernova remnants consist of a pulsar wind nebula located inside a shell-type remnant. The presence of a shell has implications on the evolution of the nebula, although the converse is generally not true. The purpose of this…
Light dark photons are subject to various plasma effects, such as Debye screening and resonant oscillations, which can lead to a more complex cosmological evolution than is experienced by conventional cold dark matter candidates.…
Starting from the assumption that the present accelerated expansion of the Universe is driven by a chameleon scalar field, the function describing a direct coupling between the matter content of the Universe and the scalar field is derived…
Various extensions of the Standard Model predict the existence of hidden photons kinetically mixing with the ordinary photon. This mixing leads to oscillations between photons and hidden photons, analogous to the observed oscillations…
Chameleons are light scalar fields with remarkable properties. Through the interplay of self-interactions and coupling to matter, chameleon particles have a mass that depends on the ambient matter density. The manifestation of the fifth…
The cosmological standard model at present is widely accepted as containing mainly things we do not understand. In particular the appearance of a Cosmological Constant, or dark energy, is puzzling. This was first inferred from the Hubble…
A model is presented where there exists another U(1) gauge group which is extremely weakly coupled to that of QED except inside the core of domain walls. It is possible to choose parameters such that standard model photons crossing such a…
A dark photon may kinetically mix with the ordinary photon, inducing oscillations with observable imprints on cosmology. Oscillations are resonantly enhanced if the dark photon mass equals the ordinary photon plasma mass, which tracks the…
We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point…
The hypothetical massive dark photon ($\gamma'$) which has kinetic mixing with the SM photon can decay electromagnetically to $e^+e^-$ pairs if its mass $m$ exceeds $2m_e$ and otherwise into three SM photons. These decays yield cosmological…
Photon-axion conversion induced by intergalactic magnetic fields causes an apparent dimming of distant sources, notably of cosmic standard candles such as supernovae of type Ia (SNe Ia). We review the impact of this mechanism on the…
We revisit the flux of chameleons (light scalar particles which could play a role in the dark energy phenomenon) produced in the interior of the Sun. Our novel analysis incorporates various important details and new processes that have…
The extreme luminosity and their fairly unique temporal behaviour have made supernovae a superb tool to measure distances in the universe. As complex astrophysical events they provide interesting insights into explosion physics, explosive…
We propose an experiment to search for extra "hidden-sector" U(1) gauge bosons with gauge kinetic mixing with the ordinary photon, predicted by many extensions of the Standard Model. The setup consists of a highly sensitive magnetometer…
It was recently argued that the observed PVLAS anomaly can be explained by chameleon field theories in which large deviations from Newton's law can be avoided. Here we present the predictions for the dichroism and the birefringence induced…