相关论文: Constraints on axion-like particles with H.E.S.S. …
Axion-like particles (ALPs) are hypothetical particles and compelling candidates for cold dark matter. Their existence could be probed through their conversions into photons in the presence of magnetic fields. In this work, we explore the…
Axions are light pseudoscalar bosons postulated with many motivations in particle physics and cosmology, including the strong CP problem and the dark matter in our Universe. In this lecture notes, we discuss a variety of known ultraviolet…
Axion-like particles with masses in the keV-GeV range have a profound impact on the cosmological evolution of our Universe, in particular on the abundance of light elements produced during Big Bang Nucleosynthesis. The resulting limits are…
We derive new constraints on the coupling of heavy pseudoscalar (axion-like) particles to photons, based on the gamma ray flux expected from the decay of these particles into photons. After being produced in the supernova core, these heavy…
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…
The detection of very high-energy (VHE) gamma rays from the active galaxy M87 by LHAASO, showing a possible spectral hardening around $20$ TeV, motivates the search for new physics beyond standard emission models. One promising candidate is…
The axion is just one from a general class of new particles -- called Light Pseudoscalar Bosons (LPBs) -- predicted by many realistic extensions of the Standard Model. We offer a somewhat pedagogical review of their main properties, with…
Axion-Like Particles (ALPs) are predicted by many extensions of the Standard Model and give rise to characteristic dimming and polarization effects in a light beam travelling in a magnetic field. In this Letter, we demonstrate that…
Several extensions of the Standard Model predict the existence of Axion-Like Particles (ALPs), very light spin-zero bosons with a two-photon coupling. ALPs can give rise to observable effects in very-high-energy astrophysics. Above roughly…
Discoveries of very high energy (VHE) photons from distant blazars suggest that, after correction by extragalactic background light (EBL) absorption, there is a flatness or even a turn-up in their spectra at the highest energies that cannot…
Axions are hypothetical pseudoscalar particles that have been regarded as promising dark matter (DM) candidates. On the other hand, extended compact objects such as axion stars, which are supported by gravity and axion self interactions,…
The axion is a light pseudoscalar particle postulated to solve issues with the Standard Model, including the strong CP problem and the origin of dark matter. In recent years, there has been remarkable progress in the physics of axions in…
Axion-like particles (ALPs) are a broad class of pseudo-scalar bosons that generically arise from broken symmetries in extensions of the standard model. In many scenarios, ALPs can mix with photons in regions with high magnetic fields.…
Axions and axion-like particles generically couple to QED via the axion-photon-photon interaction. This leads to a modification of Maxwell's equations known in the literature as axion-electrodynamics. The new form of Maxwell's equations…
Very high energy (VHE, energy >~ 100 GeV) {\gamma}-rays originating from extragalactic sources interact with low energy photons of background radiation fields and produce electron-positron pairs. Alternatively, in the presence of ambient…
Many extensions of the Standard Model predict the existence of ALPs, which are very light spin-zero bosons with a two-photon coupling. Photon-ALP oscillations occur in the presence of an external magnetic field, and ALPs can lead to…
Axions and other very light axion-like particles appear in many extensions of the Standard Model, and are leading candidates to compose part or all of the missing matter of the Universe. They also appear in models of inflation, dark…
Axion-like particles (ALPs) can decay into two photons with a rest-frame frequency given by half of the ALP mass. This implies that ultra-violet searches can be used to investigate ALPs in the multi-eV mass range. We use archival data from…
Studies of axion-like particles (ALPs) commonly focus on a single type of interaction, for example couplings only to photons. Most ALP models however predict correlations between different couplings, which change the phenomenology in…
We show that the parameter space of axion-like particles can be severly constrained using high-precision measurements of quasar polarisations. Robust limits are derived from the measured bounds on optical circular polarisation and from the…