Related papers: A timing formula for main-sequence star binary pul…
It is believed that the radio pulsars rotating at spin periods of about 30 millisecond or even lower got such high spins through the transfer of angular momentum by accreting matter from their binary companions (or past companions) in the…
We discuss precessing compact binaries on eccentric orbit with gravastar, black hole, neutron star, or boson star components. We derive secular evolution equations to second post-Newtonian--order accuracy, with leading-order spin-orbit,…
The apsidal motion of a non-synchronous binary pulsar serves as a valuable probe of relativistic gravity, stellar stricture, and dynamical evolution of close binary systems, In this study, we investigate the combined influence of general…
We report on 22 yrs of radio timing observations of the millisecond pulsar J1024$-$0719 by the telescopes participating in the European Pulsar Timing Array (EPTA). These observations reveal a significant second derivative of the pulsar spin…
This thesis focuses on the study of binary radio pulsars, their evolution and some specific use of their properties to investigate fundamental physics such as general relativity and other gravitational theories. The work that we present…
Recent observations of PSR J0045-7319, a radio pulsar in a close eccentric orbit with a massive main sequence B-star companion, indicate that the system's orbital period is decreasing on a timescale $\sim 5 x 10^{5}$ years (Kaspi et al.…
We study orbital inclination changes associated with the precession of a disc-planet system that occurs through gravitational interaction with a binary companion on an inclined orbit. We investigate whether this scenario can account for…
The stellar spin orientation relative to the orbital planes of multiplanet systems are becoming accessible to observations. Here, we analyze and classify different types of spin-orbit evolution in compact multiplanet systems perturbed by an…
We observe systematic profile changes in the visible pulsar of the compact double neutron star system PSR~J1946+2052 using observations with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The interpulse of PSR~J1946+2052…
There are two kinds of expressions on the precession of orbital plane of a binary pulsar system, which are given by Barker $&$ O'Connell (1975) and Apostolatos et al. (1994), Kidder (1995) respectively. This paper points out that these two…
We comment on a recent study reporting evidence for the general relativistic Lense-Thirring secular precession of the inclination $I$ of the orbital plane to the plane of the sky of the tight binary system PSR J1141-6545 made of a white…
Short-period binary star systems dissipate orbital energy through tidal interactions that lead to tighter, more circular orbits. When at least one star in a binary has evolved off of the main sequence, orbital circularization occurs for…
The spin-down of a millisecond pulsar in a compact binary system leads to self-energy losses, that cause the binary's orbital period to increase (the effect being of first post-Newtonian (1PN) order). If the pulsar's period-derivative is…
Recent timing observations have revealed the presence of orbital precession due to spin-orbit coupling and rapid orbital decay due to dynamical tidal interaction in the PSR J0045-7319/B-star binary system. They can be used to put concrete…
(abridged) PSR J1903+0327, a millisecond pulsar in an eccentric (e = 0.44) 95-day orbit with a (~ 1Msun) companion poses a challenge to our understanding of stellar evolution in binary and multiple-star systems. Here we describe optical and…
The recent discovery of a double-pulsar PSR J0737-3039A/B provides an opportunity of unequivocally observing, for the first time, spin effects in general relativity. Existing efforts involve detection of the precession of the spinning body…
In this paper we give the first attempt to model the evolution of the spectrum of PSR B1259$-$63 radio emission while the pulsar orbits the companion Be star. As suggested by Kijak et al. (Mon. Not. R. Astron. Soc. 418:L114, 2011a) this…
We report the results of timing observations of PSR J1952+2630, a 20.7 ms pulsar in orbit with a massive white dwarf companion. With the increased timing baseline, we obtain improved estimates for astrometric, spin, and binary parameters…
For radio pulsars in orbit with a compact companion, pulsar timing observations have proved to be a powerful tool for identifying the physical nature of the companion. Unfortunately, perhaps the most intriguing system where such a tool…
The Lense-Thirring effect from spinning neutron stars in double neutron star binaries contribute to the periastron advance of the orbit. This extra term involves the moment of inertia of the neutron stars. Moment of inertia, on the other…