Related papers: A New Search Technique for Short Orbital Period Bi…
Transiting planets manifest themselves by a periodic dimming of their host star by a fixed amount. On the other hand, light curves of transiting circumbinary (CB) planets are expected to be neither periodic nor to have a single depth while…
Radio timing observations of a millisecond pulsar in orbit around the Galactic centre black hole (BH) or a BH at the centre of globular clusters could answer foundational questions in astrophysics and fundamental physics. Pulsar radio…
We investigate the number and type of pulsars that will be discovered with the low-frequency radio telescope LOFAR. We consider different search strategies for the Galaxy, for globular clusters and for other galaxies. We show that a 25-day…
Precision tests of general relativity can be conducted by observing binary pulsars. Theories with massive fields exist to explain a variety of phenomena from dark energy to the strong CP problem. Existing pulsar binaries, such as the white…
Rapidly spinning neutron stars with non-axisymmetric mass distributions are expected to generate quasi-monochromatic continuous gravitational waves. While many searches for unknown, isolated spinning neutron stars have been carried out,…
The new photometric space-borne survey missions CoRoT and Kepler will be able to detect minute flux variations in binary stars due to relativistic beaming caused by the line-of-sight motion of their components. In all but very short period…
Observing gravitational waves from sub-solar-mass, inspiraling compact binaries would provide almost smoking-gun evidence for primordial black holes. Here, we develop a method to search for ultra-compact binaries with chirp masses ranging…
Millisecond pulsars in tight binaries have recently opened new challenges in our understanding of physical processes governing the evolution of binaries and the interaction between astrophysical plasma and electromagnetic fields.…
Efforts are underway to use high-precision timing of pulsars in order to detect low-frequency gravitational waves. A limit to this technique is the timing noise generated by dispersion in the plasma along the line of sight to the pulsar,…
We searched for eclipses of two millisecond pulsars, PSR J1807-2459 and PSR B1908+00. These pulsars are in very low mass binary systems with orbital parameters similar to those of eclipsing binaries. Observations were made with the GBT at…
The X-ray signal from active galactic nuclei and black hole X-ray binaries is highly variable on a range of timescales. This variability can be exploited to map the region of interest close to the black hole, which is far too small to…
Resolvable Supermassive Black Hole Binaries are promising sources for Pulsar Timing Array based gravitational wave searches. Search algorithms for such targets must contend with the large number of so-called pulsar phase parameters in the…
Pulsar timing has enabled some of the strongest tests of fundamental physics. Central to the technique is the assumption that the detected radio pulses can be used to accurately measure the rotation of the pulsar. Here we report on a…
Pulsar Timing Arrays (PTAs) have recently found strong evidence for low-frequency gravitational waves (GWs) in the nanohertz frequency regime. As GWs pass, they produce deviations in measured lengths and light-travel times. PTA experiments…
Supermassive black hole binaries are one of the primary targets for gravitational wave searches using pulsar timing arrays. Gravitational wave signals from such systems are well represented by parametrized models, allowing the standard…
X-ray binary systems consist of a companion star and a compact object in close orbit. Thanks to their copious X-ray emission, these objects have been studied in detail using X-ray spectroscopy and timing. The inclination of these systems is…
We propose a new method to detect off-pulse (unpulsed and/or continuous) emission from pulsars, using the intensity modulations associated with interstellar scintillation. Our technique involves obtaining the dynamic spectra, separately for…
We report the first hard X-ray (3-79 keV) observations of the millisecond pulsar (MSP) binary PSR J1023+0038 using NuSTAR. This system has been shown transiting between a low-mass X-ray binary (LMXB) state and a rotation-powered MSP state.…
The high stellar density in the central parsecs around the Galactic Centre makes it a seemingly favourable environment for finding relativistic binary pulsars. These include pulsars orbiting other neutron stars, stellar-mass black holes or…
Millisecond pulsars represent an evolutionarily distinct group among rotation-powered pulsars. Outside the radio band, the soft X-ray range ($\sim 0.1$--10 keV) is most suitable for studying radiative mechanisms operating in these…