Related papers: Does Pulsar B1757--24 Have a Fallback Disk?
We examine the effects of a relativistic wind on the spin down of a neutron star and apply our results to the study of Soft Gamma Repeaters (SGRs), thought to be neutron stars with magnetic fields > 10^{14} G. We derive a spin-down formula…
Dramatic torque reversals between spin up and spin down have been observed in half of the persistent X-ray pulsars monitored by the BATSE all-sky monitor on CGRO. Theoretical models developed to explain early pulsar timing data can explain…
Neutron stars may be surrounded by fall-back disks formed from supernova core-collapse. If the disk circumscribes the light-cylinder, the neutron star will be an active radio pulsar spinning down under the propeller spin-down torque applied…
The observed long-term spin-down evolution of isolated radio pulsars cannot be explained by the standard magnetic dipole radiation with a constant braking torque. However, how and why the torque varies still remains controversial, which is…
Numerical simulations predict that the spin-down rate of a single rotation-powered neutron star depends on the angle $\alpha$ between its spin and magnetic axes as $P\dot P \propto \mu^2 (k_0 + k_1\sin^2\alpha)$, where $P$ is the star spin…
Enigmatic transitions between spin-up and spin-down have been observed in several X-ray pulsars accreting matter via an accretion disk. In these transitions, the torque changes sign but remains at nearly the same magnitude. It has been…
Recent timing observation reported that the radio pulsar PSR J1734 - 3333 with a rotating period $P=1.17~\rm s$ is slowing down with a period derivative $\dot{P}=2.28\times 10^{-12}\rm s\,s^{-1}$. Its derived braking index $n=0.9 \pm 0.2$…
Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a…
With the ever-increasing sensitivity and timing baselines of modern radio telescopes, a growing number of pulsars are being shown to exhibit transitions in their rotational and radio emission properties. In many of these cases, the two are…
Recent timing observations of PSR J0045-7319 reveal that the neutron star/B star binary orbit is decaying on a time scale of $|\Porb/\dot\Porb|=0.5$ Myr, shorter than the characteristic age ($\tau_c=3$ Myr) of the pulsar (Kaspi et…
Millisecond pulsars are old neutron stars that have been spun up to high rotational frequencies via accretion of mass from a binary companion star. An important issue for understanding the physics of the early spin evolution of millisecond…
RADIO pulsars are thought to born with spin periods of 0.02-0.5 s and space velocities of 100-1000 km/s, and they are inferred to have initial dipole magnetic fields of 10^{11}-10^{13}. The average space velocity of a normal star in the…
Pulsars are rotating, magnetized neutron stars that are born in supernova explosions following the collapse of the cores of massive stars. If some of the explosion ejecta fails to escape, it may fall back onto the neutron star or it may…
The spin behaviour of the neutron star in the newly discovered young Be/X-ray long-period pulsar SXP 1062 is discussed. The star is observed to rotate with the period of 1062s, and spin-down at the rate ~ - 2.6 \times 10^{-12} Hz s^{-1}. I…
We investigate the age constraints that can be placed on the double pulsar system using models for the spin-down of the first-born 22.7-ms pulsar A and the 2.77-s pulsar B with characteristic ages of 210 and 50 Myr respectively. Standard…
As presented by Nice et al. (2000), long-term timing of the eclipsing binary PSR B1744-24A shows that the orbital period of this system decreases with a time-scale of only ~ 200 Myr. To explain the much faster orbital period decay than that…
Neutron stars such as pulsars and magnetars lose angular momentum primarily through electromagnetic dipole radiation, gravitational waves, $r$-mode oscillation, and also affected by fallback accretion processes. However, anomalous spin…
Positive and negative pulsar breaking indices suggest that some fraction of the pulsar spindown torque undergoes a cyclic evolution. The observed strong correlation of `anomalous' breaking indices with pulsar age implies that the…
Pulsars are famed for their rotational clock-like stability and their highly-repeatable pulse shapes. However, it has long been known that there are unexplained deviations (often termed "timing noise") from the rate at which we predict…
Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a…