Related papers: Pulsar Astrometry at the Microarcsecond Level

In order to understand the nature of the lenses that generate microlensing events, one would like to measure their mass, distance, and velocity. Unfortunately, current microlensing experiments measure only one parameter of the events, the…

The existence of a population of millisecond pulsars in the Galactic bulge is supported, along with other evidence, by the Fermi GeV excess, an anomalous {\gamma}-ray emission detected almost 15 years ago in the direction of the Galactic…

Pulsars, if existing and detectable in the immediate vicinity of the massive black hole (MBH) in the Galactic center (GC), may be used as a superb tool to probe both the environment and the metric of the central MBH. The recent discovery of…

Recent advances with the VLBA have resulted in ~10 micro-arcsec astrometry for compact sources in external galaxies, and measurement of the proper motion of Local Group galaxies has been demonstrated. With improved telescopes and equipment,…

We present our search program for substellar companions using high-precision relative astronomy. Due to its orbital motion around the star, an unseen substellar companion would produce a periodic "wobble" of the host star, which is the…

Pulsars are fantastic objects, which show the extreme states of matters and plasma physics not understood yet. Pulsars can be used as probes for the detection of interstellar medium and even the gravitational waves. Here I review the basic…

Recent advances in radio astrometry with the VLBA have resulted in near micro-arcsecond accurate trigonometric parallax and proper motion measurements for masers in star forming regions. We are now poised to directly measure the full…

We present strong observational evidence for a relationship between the direction of a pulsar's motion and its rotation axis. We show carefully calibrated polarization data for 25 pulsars, 20 of which display linearly polarized emission…

We aim to measure very precise and accurate model-independent masses and distances of detached binary stars. Precise masses at the $< 1$% level are necessary to test and calibrate stellar interior and evolution models, while precise and…

Results are presented from a long-term astrometry program on PSR B0919+06 using the NRAO Very Long Baseline Array. With ten observations (seven epochs) between 1994--2000, we measure a proper motion of 18.35 +/- 0.06 mas/yr in RA, 86.56 +/-…

(Abridged) This thesis describes the development of DiFX, the first general-purpose software correlator for radio interferometry, and its use with the Australian Long Baseline Array (LBA) to complete the largest VLBI pulsar astrometry…

The launch of the Fermi Gamma-ray Space Telescope has heralded a new era in the study of gamma-ray pulsars. The population of confirmed gamma-ray pulsars has gone from 6-7 to more than 60, and the superb sensitivity of the Large Area…

The phenomenal rotational stability of millisecond pulsars allows them to be used as precise celestial clocks. An array of these pulsars can be exploited to search for correlated perturbations in their pulse times of arrival due to…

Recent proper motion and parallax measurements for the pulsar PSR B1508+55 indicate a transverse velocity of ~1100 km/s, which exceeds earlier measurements for any neutron star. The spin-down characteristics of PSR B1508+55 are typical for…

We conducted targeted fast radio burst (FRB) and pulsar searches on eight pulsing ultraluminous X-ray sources (PULXs) using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) and the Parkes 64-meter Radio Telescope (Murriyang)…

We propose a pulsar candidate cross matching algorithm to sift radio pulsar search candidates from repeated observations of the same sky location such as globular clusters, high energy sources, or supernova remnants. Our method uses both…

After a brief introduction into the asteroseismic modelling of stars, we provide a compilation of the current seismic estimates of the core overshooting parameter and of the rotational frequency of single and binary massive stars. These…

Precise millisecond pulsar (MSP) positions determined with very long baseline interferometry (VLBI) hold the key to building the connection between the kinematic and dynamic reference frames respectively used by VLBI and pulsar timing. The…

Measurement of accurate positions, pulse periods and period derivatives is an essential follow-up to any pulsar survey. The procedures being used to obtain timing parameters for the pulsars discovered in the Parkes multibeam pulsar survey…

Astrometric measurements of microlensing events can in principle determine both the "parallax" \tilde r_E and the "proper motion" \mu of an individual event which (combined with the Einstein time scale t_E) in turn yield the mass, distance,…