Related papers: Shadows of a maximal acceleration
Supermagnified stars are gravitationally lensed individual stars that are located close to a caustic of a lensing galaxy cluster, and have their flux magnified by a large enough factor (typically ~ 1000) to make them detectable with present…
Neutron stars contain matter in one of the densest forms found in the Universe. This feature, together with the unprecedented progress in observational astrophysics, makes such stars superb astrophysical laboratories for a broad range of…
We study the effects of dark matter on the structural properties of neutron stars. In particular we investigate how the presence of a dark matter component influences the mass-radius relation, the value of the maximum mass of a neutron star…
We report constraints on the nucleon-dark matter particle cross section using the internal luminosity of observed white dwarf stars in the globular cluster Messier 4. Our results cover the parameter space corresponding to relatively light…
The best upper bounds on the masses of stable and unstable light neutrinos derive from the upper bound on the total mass density, as inferred from the lower limit $t_0> 13$ Gyr on the dynamical age of the Universe: If the Universe is…
When hadron-quark continuity is formulated in terms of a topology change at a density higher than twice the nuclear matter densiy $n_0$ the core of massive compact stars can be described in terms of quasiparticles of fractional baryon…
We investigate medium effects due to density-dependent magnetic moments of baryons on neutron stars under strong magnetic fields. If we allow the variation of anomalous magnetic moments (AMMs) of baryons in dense matter under strong…
We have determined the location of the line-opacity modified Eddington limit for stars in the LMC using the most recent atmosphere models combined with a precise mapping to the HR Diagram through up-to-date stellar evolution calculations.…
We investigate the hadron-quark phase transition in cold neutron stars in light of (i) the observed limits on the maximum-mass of heavy pulsars, (ii) constraints on the tidal properties inferred from the gravitational waves emitted in…
We use the dynamical heating of stars in ultrafaint dwarf (UFD) galaxies to set limits on Massive Compact Halo Objects (MACHOs). In our analysis we study the robustness of the bounds under uncertainties in key UFD parameters, such as the…
Compact stars consisting of fermions with arbitrary masses and interaction strengths are studied by solving the structure equation of general relativity, the Tolman-Oppenheimer-Volkoff equations. Scaling solutions are derived for a free and…
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 study the effects of strong magnetic fields on the neutron star structure. If the interior field of a star is on the same order of the surface field currently observed, the influences of the magnetic field on the star mass and radius are…
Modified gravity theories can introduce modifications to the Poisson equation in the Newtonian limit. As a result, we expect to see interesting features of these modifications inside stellar objects. White dwarf stars are one of the most…
A dark energy component is responsible for the present stage of acceleration of our universe. If no fine tuning is assumed on the dark energy potential then it will end up dominating the universe at late times and the universe will not stop…
Stars have been recognized as optimal laboratories to probe axion properties. In the last decades there have been significant advances in this field due to a better modelling of stellar systems and accurate observational data. In this work…
Some time ago we have derived from the QCD Lagrangian an equation of state (EOS) for the cold quark matter, which can be considered an improved version of the MIT bag model EOS. Compared to the latter, our equation of state reaches higher…
The question of whether quark matter exists in neutron stars is a long standing one. Generally one finds that a first order phase transition from baryons to quarks softens the equation of state so much that the star would collapse into a…
The effect of C-field in high density matter has been studied. We find that the negative energy and negative pressure of the C-field helps in formation of massive compact stable neutron stars of mass $\sim$ 0.5 solar mass which is in the…
We investigate nuclear matter equations of state in neutron star with kaon condensation. It is generally known that the existence of kaons in neutron star makes the equation of state soft so that the maximum mass of neutron star is not…