Related papers: New constraints on very light pseudoscalars
The standard axion-like particle explanation of the observed large-scale coherent orientations of quasar polarisation vectors is ruled out by the recent measurements of vanishing of circular polarisation. We introduce a more general…
Probing the existence of hypothetical particles beyond the Standard model often deals with extreme parameters: large energies, tiny cross-sections, large time scales, etc. Sometimes laboratory experiments can test required regions of…
Pseudoscalar particles like axion-like particles generically couple to two photons, giving rise to the possibility of oscillations with photons in an external magnetic field. These oscillations could lead to measurable imprints in the…
We comment on the recent experimental results from the PVLAS and CAST collaborations that search for axion-like particles. We propose a particle physics model in which their apparent inconsistency is circumvented.
We propose a new method to search for light (pseudo-)scalar particles in the spectra of compact astrophysical objects such as magnetars, pulsars, and quasars. On accounts of compact astrophysical objects having intense magnetic fields…
Axions are hypothetical particles related to the violation of the charge-parity symmetry, being the most prone candidates for dark matter. Multiple attempts to prove their existence are currently performed in different physical systems.…
The PVLAS signal has led to the proposal of many experiments searching for light bosons coupled to photons. The coupling strength probed by these near future searches is, however, far from the allowed region, if astrophysical bounds apply.…
The PVLAS collaboration has obtained results that may be interpreted in terms of a light axion-like particle, while the CAST collaboration has not found any signal of such particles. Moreover, the PVLAS results are in gross contradiction…
We revisit the limit on very light axion-like particles (ALPs) from the absence of gamma rays coincidental with the neutrino burst from SN1987A. We use updated supernova simulations, modern models for the magnetic field inside the Galaxy,…
Physics beyond the Standard Model predicts the possible existence of new particles that can be searched at the low energy frontier in the sub-eV range. The OSQAR photon regeneration experiment looks for "Light Shining through a Wall" from…
Stellar energy loss arguments lead to strong constraints on the coupling $\phi \gamma \gamma$ of a light axion-like particle to two photons. Helioscopes, like CAST, are able to put competitive bounds. The PVLAS experiment has recently…
Non-relativistic QCD axions or axion-like particles are among the most popular candidates for cold Dark Matter (DM) in the universe. We proposed to detect axion-like DM, using linearly polarized pulsar light as a probe. Because of…
Dark matter may consist of axion-like particles (ALPs). When polarized electromagnetic radiation passes through the dark-matter media, interaction with background ALPs affects the polarization of photons. The condensate of axionic dark…
New particles can manifest their effects in many settings, ranging from effects on sub-atomic to galactic length scales. The nature of these effects depends on the specific particles and their non-gravitational interactions. In this…
The high-energy Universe is potentially a great laboratory for searching new light bosons such as axion-like particles (ALPs). Cosmic sources are indeed the scene of violent phenomena that involve strong magnetic field and/or very long…
Very light pseudoscalar fields, often referred to as axions, are compelling dark matter candidates and can potentially be detected through their coupling to the electromagnetic field. Recently a novel detection technique using the cosmic…
A pseudoscalar or scalar particle $\phi$ that couples to two photons but not to leptons, quarks and nucleons would have effects in most of the experiments searching for axions, since these are based on the $a \gamma \gamma $ coupling. We…
Axion-like particles (ALPs), a class of pseudoscalars common to many extensions of the Standard Model, have the capacity to drain energy from the interiors of stars. Consequently, stellar evolution can be used to derive many constraints on…
Weakly coupled, almost massless, spin 0 particles have been predicted by many extensions of the standard model of particle physics. Recently, the PVLAS group observed a rotation of polarization of electromagnetic waves in vacuum in the…
Based on a sample of 355 quasars with significant optical polarization, we found that quasar polarization vectors are not randomly oriented over the sky as naturally expected. The probability that the observed distribution of polarization…