相关论文: Can Planet 9 be an Axion Star?
We investigate the decay of condensates of scalars in a field theory defined by $V({\cal A})=m{}^2\,f{}^2\,[1-\cos({\cal A}\,/\,f)]$, where $m$ and $f$ are the mass and decay constant of the scalar field. An example of such a theory is that…
Correlations in the orbits of several minor planets in the outer solar system suggest the presence of a remote, massive Planet Nine. With at least ten times the mass of the Earth and a perihelion well beyond 100 AU, Planet Nine poses a…
We propose experimental schemes for detection an axionic condensate supposed to be cosmic dark matter. Various procedures are considered in dependence on the value of the axion mass. There are well known indications that a large part of the…
Axion physics is briefly reviewed. Constraints from laboratory searches, astrophysics and cosmology require the axion mass to be in the range $10^{-6} \lesssim m_a < 3\cdot 10^{-3}$eV. Near the lower end of this range, axions are all or a…
The radiation mechanism of fast radio bursts (FRBs) has been extensively studied but still remains elusive. In the search for dark matter candidates, the QCD axion and axionlike particles (ALPs) have emerged as prominent possibilities.…
Axions and axion-like particles are ubiquitous in extensions of the Standard Model and offer a unifying framework for addressing open problems in cosmology. Depending on their mass and interactions, axions can act as dark matter, drive…
An axion rotating in field space can produce dark photons in the early universe via tachyonic instability. This explosive particle production creates a background of stochastic gravitational waves that may be visible at pulsar timing arrays…
Axions are some of the best motivated particles beyond the Standard Model. We show how the attractive self-interactions of dark matter (DM) axions over a broad range of masses, from $10^{-22}$ eV to $10^7$ GeV, can lead to nongravitational…
In light-shining-through-walls experiments, axions and axion-like particles (ALPs) are searched for by exposing an optically thick barrier to a laser beam. In a magnetic field, photons could convert into ALPs in front of the barrier and…
Photons may convert to axion-like particles (ALPs) in external magnetic fields. Under certain conditions, this effect should result in irregular features in observed spectra of astrophysical sources. Lack of such irregularities in…
Axions, encompassing both QCD axions and axion-like particles, can generate loop-induced quadratic couplings to electromagnetic field strength tensors, resulting in oscillatory shifts of the fine-structure constant. Near a Kerr black hole,…
Asymmetric dark matter under certain conditions could form compact star-like objects, which can be searched either through gravitational lensing or by observation of gravitational waves from binaries involving such compact objects. In this…
Light (pseudo-)scalar fields are promising candidates to be the dark matter in the Universe. Under certain initial conditions in the early Universe and/or with certain types of self-interactions, they can form compact dark-matter objects…
The axion is a pseudo-Nambu-Goldstone boson. It appears after the spontaneous breaking of the Peccei-Quinn symmetry, which was proposed to solve the strong-CP problem. Other pseudo-Nambu-Goldstone bosons, postulated in some extensions of…
Light axion fields, if they exist, can be sourced by neutron stars due to their coupling to nuclear matter, and play a role in binary neutron star mergers. We report on a search for such axions by analysing the gravitational waves from the…
The QCD axion is expected to form dense structures known as axion miniclusters if the Peccei-Quinn symmetry is broken after inflation. Miniclusters that have survived until today will interact with neutron stars (NSs) in the Milky Way to…
Heavy axion-like particles (ALPs), with masses up to a few 100 keV and coupled with photons can be efficiently produced in stellar plasmas, contributing to a significant energy-loss. This argument has been applied to helium burning stars in…
The axion solution of the strong CP problem provides a number of possible windows to physics beyond the standard model, notably in the form of searches for solar axions and for galactic axion dark matter, but in a broader context also…
The axion-like particles (ALPs) are very good candidates of the cosmological dark matter, which can exist in many extensions of the standard model (SM). The mass range of the ALPs as the dark matter can extend from a sub-eV scale to almost…
Ultra light particles $(m_a \sim 10^{-21}eV-10^{-22}eV)$ with axion-like couplings to other particles can be candidates for fuzzy dark matter (FDM) if the axion decay constant $f_a\sim 10^{17}GeV$. If a compact star is immersed in such a…