Related papers: Distant Companions and Planets around Millisecond …
Millisecond pulsars (MSPs) are mainly characterised by their spin periods, B-fields and masses - quantities which are largely affected by previous interactions with a companion star in a binary system. In this paper, we investigate the…
This paper explores the stability of an Earth-like planet orbiting a solar-mass star in the presence of a stellar companion using ~ 400,000 numerical integrations. Given the chaotic nature of the systems being considered, we perform a…
We present a high-precision timing analysis of PSR J1933$-$6211, a millisecond pulsar (MSP) with a 3.5-ms spin period and a white dwarf (WD) companion, using data from the Parkes radio telescope. Since we have accurately measured the…
Precision timing of millisecond pulsars in binary systems enables observers to detect the relativistic Shapiro delay induced by space time curvature. When favourably aligned, this enables constraints to be placed on the component masses and…
Radial velocity searches may lead to detection of exoplanets at large orbital separations only if long-enough time-series of data are available. Therefore publication of precise measurements collected in the past is very valuable even if…
In 2012, five high school students involved in the Pulsar Search Collaboratory discovered the millisecond pulsar PSR J1400$-$1431 and initial timing parameters were published in Rosen et al. (2013) a year later. Since then, we have obtained…
Long-period binary systems containing a B-type hot subdwarf (sdB) and a main-sequence companion are thought to originate from binary interactions involving stable mass transfer from the red giant, the progenitor of the sdB, to the MS…
We conducted a timing analysis of over 18 years of data on the young ($\tau_{\rm c} = 112$ kyr, $P = 114$\,ms) relativistic binary PSR~J1906+0746, using six radio telescopes: Arecibo, FAST, Green Bank, Lovell, MeerKAT, and Nan\c{c}ay. This…
Polaris, the nearest and brightest classical Cepheid, is a member of at least a triple system. It has a wide ($18''$) physical companion, the F-type dwarf Polaris B. Polaris itself is a single-lined spectroscopic binary with an orbital…
Context. PSR J0312$-$0921 and PSR J1627$+$3219 are black widow pulsars with orbital periods of 2.34 and 3.98 hours. They were recently detected in the radio and $\gamma$-rays. Aims. Our goals are to estimate the fundamental parameters of…
The orbital parameters of binaries at intermediate periods ($10^2$--$10^3$ d) are difficult to measure with conventional methods and are very incomplete. We have undertaken a new survey, applying our pulsation timing method to {\it Kepler}…
Dwarf galaxies and globular clusters may contain intermediate mass black holes ($10^{3}$ to $10^{5}$ solar masses) in their cores. Estimates of ~$10^{3}$ neutron stars in the central parsec of the Galaxy and similar numbers in small…
We have monitored a large sample of millisecond pulsars using the 100-m Effelsberg radio telescope in order to compare their radio emission properties to the slowly rotating population. With some notable exceptions, our findings suggest…
The frequency dependent eclipses of the radio emission from millisecond pulsars (MSPs) in compact binary systems provide an opportunity to understand the eclipse mechanism and to determine the nature of the eclipsing medium. We combine…
Millisecond and binary pulsars are the most stable natural frequency standards which admits to introduce modified versions of universal and ephemeris time scales based correspondingly on the intrinsic rotation of pulsar and on its orbital…
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…
Typical radio pulsars are magnetized neutron stars that are born rapidly rotating and slow down as they age on time scales of 10 to 100 million years. However, millisecond radio pulsars spin very rapidly even though many are billions of…
We present the timing parameters of nine pulsars discovered in a survey of intermediate Galactic latitudes at 1400 MHz with the Parkes radio telescope. Eight of these pulsars possess small pulse periods and period derivatives thought to be…
PSR J1740-3052 is a young pulsar in orbit around a companion that is most likely a B-type main-sequence star. Since its discovery more than a decade ago, data have been taken at several frequencies with instruments at the Green Bank,…
Observations of pulsar timing provide strong constraints on scalar-tensor theories of gravity, but these constraints are traditionally quoted as limits on the microscopic parameters (like the Brans-Dicke coupling, for example) that govern…