Related papers: Dynamical evolution of fermion-boson stars
We perform numerical evolutions of the fully non-linear Einstein-(complex, massive)Klein-Gordon and Einstein-(complex)Proca systems, to assess the formation and stability of spinning bosonic stars. In the scalar/vector case these are known…
What if the dark matter-nucleon scattering cross section is too small to be detected by direct detection experiments? It is well known in the literature that some interactions lead to dark matter-nucleon scattering cross sections that can…
Boson stars are gravitationally bound objects that arise in ultralight dark matter models and form in the centers of galactic halos or axion miniclusters. We systematically study the excitations of a boson star, taking into account the…
Different types of gravitating compact objects occuring in d=5 space-time are considered: boson stars, hairy black holes and perfect fluid solutions. All these solutions of the Einstein equations coupled to matter have well established…
We consider compact boson stars that arise for a V-shaped scalar field potential. They represent a one parameter family of solutions of the scaled Einstein-signum-Gordon equations. We analyze the physical properties of these solutions and…
If there is a scalar boson field interacting dominantly with a quark or a lepton in the thermal background, its coherent oscillation can be generated through the thermal effect and becomes a good dark matter candidate in a wide range of the…
White dwarfs (WDs) can be used as laboratories to test strong gravity and high-density regimes, once their equation of state is not so uncertain as the one of neutron stars. This makes them also a useful tool to constrain dark-matter…
We investigate neutron star-black hole (NS-BH) merger candidates as a test for compact exotic objects. Using the events GW190814, GW200105 and GW200115 measured by the LIGO-Virgo collabration, which represent a broad profile of the masses…
There is accumulating evidence that (fundamental) scalar fields may exist in Nature. The gravitational collapse of such a boson cloud would lead to a boson star (BS) as a new type of a compact object. Similarly as for white dwarfs and…
In [Leung et al., Phys. Rev. D 84, 107301 (2011)], we presented our results on using a general relativistic two-fluid formalism to study the hydrostatic equilibrium configuration of an admixture of degenerate dark matter and normal nuclear…
We study the effects of dark matter on the properties of neutron stars by employing a DM-admixed model. The Brueckner-Hartree-Fock theory with realistic three-body forces and a generic bosonic self-interacting dark matter model describe the…
Ultra-light bosons, naturally appearing in well-motivated extensions to the Standard Model, can constitute all the dark matter. Models with particle mass close to the smallest phenomenologically allowed exhibit coherent field configurations…
A model of static boson-fermion star with spherical symmetry based on the scalar-tensor theory of gravity with massive dilaton field is investigated numerically. Since the radius of star is \textit{a priori} an unknown quantity, the…
We analyze the physical properties of boson stars, which possess counterparts in flat space-time, Q-balls. Applying a stability analysis via catastrophe theory, we show that the families of rotating and non-rotating boson stars exhibit two…
In the context of the standard model of particle physics, there is a definite upper limit to the density of stable compact stars. However, if there is a deeper layer of constituents, below that of quarks and leptons, stability may be…
In this work we consider minimally-coupled boson stars immersed in a tidal environment and compute their tidal deformability to leading order. We also describe an approximate correspondence between Newtonian boson star configurations…
We review severe constraints on asymmetric bosonic dark matter based on observations of old neutron stars. Under certain conditions, dark matter particles in the form of asymmetric bosonic WIMPs can be effectively trapped onto nearby…
We showed that compact bosonic objects can be formed through a process we called gravitational cooling. A central issue in the subject of boson star is whether a classical field configuration, {\it e.g.,} one described by the Klein-Gordon…
In this lecture, we give a first introduction to neutron stars, based on fundamental physical principles. After outlining their outstanding macroscopic properties, as obtained from observations, we infer the extreme conditions of matter in…
Recent observational results for the masses and radii of some neutron stars are in contrast with typical observations and theoretical predictions for "normal" neutron stars. We propose that their unusual properties can be interpreted as the…