Related papers: Binary Pulsars as probes for Spin-2 Ultralight Dar…
We present numerical calculations of the photon-light-pseudoscalar-boson conversion in the recently discovered binary pulsar system J0737-3039. Light pseudoscalar bosons (LPBs) oscillate into photons in the presence of strong magnetic…
In this paper we review the recent discovery of several millisecond pulsars (MSPs) in eccentric binary systems. Timing these MSPs we were able to estimate (and in one case precisely measure) their masses. These results suggest that, as a…
The study of ultralight dark matter helps to constrain the lower bound of the mass in minimally coupled dark matter models. The granular structure of ultralight dark matter density fields produces metric perturbations which have been…
It is difficult to discover pulsars via their gamma-ray emission because current instruments typically detect fewer than one photon per million rotations. This creates a significant computing challenge for isolated pulsars, where the…
This talk reviews the constraints imposed by binary-pulsar data on gravity theories, and notably on "scalar-tensor" theories which are the most natural alternatives to general relativity. Because neutron stars have a strong gravitational…
The merger of binary pulsars in dark matter (DM)-rich environments can result in DM particle accretion, leading to an increase in the individual pulsar masses. In this work, we investigate the effects of DM accretion on the change in…
We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the…
A coherently oscillating ultra-light axion can behave as dark matter. In particular, its coherently oscillating pressure perturbations can source an oscillating scalar metric perturbation, with a characteristic oscillation frequency which…
Pulsars, highly magnetized, rotating neutron stars, can have significant muon abundances in their dense cores, making them promising environments to probe ultralight mediators coupled to muons. The precise measurement of periastron advance…
Dark matter is obtained from a scalar field coupled conformally to gravitation; the scalar being a relict of Dirac's gauge function. This conformally coupled dark matter includes a gas of very light ($m\approx 2.25\times 10^{-34} eV$)…
Binary pulsar systems are superb probes of stellar and binary evolution and the physics of extreme environments. In a survey with the Arecibo telescope, we have found PSR J1903+0327, a radio pulsar with a rotational period of 2.15 ms in a…
Compact binary coalescences are the most promising sources of gravitational waves (GWs) for ground based detectors. Binary systems containing one or two spinning black holes are particularly interesting due to spin-orbit (and eventual…
In models where ultralight fields constitute dark matter, the misalignment mechanism leads to coherent, low-amplitude oscillations in fundamental constants. This effect arises from effective operators that couple dark matter to Standard…
We study the capture of dark matter particles by neutron stars in close binary systems. By performing a direct numerical simulation, we find that there is a sizable amplification of the rate of dark matter capture by each of the companions.…
Ultralight (or fuzzy) dark matter (ULDM) is an alternative to cold dark matter. A key feature of ULDM is the presence of solitonic cores at the centers of collapsed halos. These would potentially increase the drag experienced by…
In this paper we consider $\phi^2$ scalar field potential as a candidate to dark matter. If it is an ultralight boson particle, it condensates like a Bose-Einstein system at very early times and forms the basic structure of the Universe.…
The dark photon, an new hypothetical light spin 1 field, constitutes a well-motivated dark matter candidate. It manifests as an oscillating electric field with a fixed direction, which can be observed in magnetometric records. In this…
Many physically motivated extensions to general relativity (GR) predict significant deviations in the properties of spacetime surrounding massive neutron stars. We report the measurement of a 2.01 +/- 0.04 solar mass pulsar in a 2.46-hr…
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…
Binary systems comprising at least one neutron star contain strong gravitational field regions and thereby provide a testing ground for strong-field gravity. Two types of data can be used to test the law of gravity in compact binaries:…