相关论文: Evidence for chaotic behaviour in pulsar spin-down…

We observe the occurrence of a strange nonchaotic attractor in a periodically driven two-dimensional map, formerly proposed as a neuron model and a sequence generator. We characterize this attractor through the study of the Lyapunov…

Strange nonchaotic attractors (SNAs) are observed in quasiperiodically driven time--delay systems. Since the largest Lyapunov exponent is nonpositive, trajectories in two such identical but distinct systems show the property of {\it…

Periodic modulations are seen in normal period pulsars ($P >$ 0.1 sec) over timescales ranging from a few seconds to several minutes. Such modulations have usually been associated with the phenomenon of subpulse drifting. A number of recent…

We investigate the impact of noise processes on high-precision pulsar timing. Our analysis focuses on the measurability of the second spin frequency derivative $\ddot{\nu}$. This $\ddot{\nu}$ can be induced by several factors including the…

This paper presents a new chaotic system having four attractors, including two fixed point attractors and two symmetrical chaotic strange attractors. Dynamical properties of the system, viz. sensitive dependence on initial conditions,…

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…

The dynamics of unidirectionally coupled chaotic Lorenz systems is investigated. It is revealed that chaos is present in the response system regardless of generalized synchronization. The presence of sensitivity is theoretically proved, and…

We present a comprehensive analysis of AstroSat/LAXPC data of the second spin-up and second spin-down phases of the persistent X-ray pulsar 4U 1626-67. Flares followed by a broad dip are detected in the spin-up observations. The pulse…

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…

We report the discovery of two young isolated radio pulsars with very high inferred magnetic fields. PSR J1119-6127 has period P = 0.407 s, and the largest period derivative known among radio pulsars, Pdot = 4.0e-12. Under standard…

It is thought that isolated neutron stars receive a natal kick velocity at birth nearly aligned with their spin axis. Direct observational confirmation of this alignment is currently limited to a single source in a supernova remnant (PSR…

Strange nonchaotic attractors (SNAs), which are realized in many quasiperiodically driven nonlinear systems are strange (geometrically fractal) but nonchaotic (the largest nontrivial Lyapunov exponent is negative). Two such identical…

Radio pulsars are thought to spin-down primarily due to torque from magnetic dipole radiation (MDR) emitted by the time-varying stellar magnetic field as the star rotates. This assumption yields a `characteristic age' for a pulsar which has…

The period doubling phenomenon was recently discovered in RR Lyrae stars with the Kepler space telescope and has been theoretically explained by hydrodynamic calculations. However, peculiar solutions of the Florida-Budapest turbulent…

We have observed a total of 67 pulsars at five frequencies ranging from 243 to 3100 MHz. Observations at the lower frequencies were made at the Giant Metre Wave Telescope in India and those at higher frequencies at the Parkes Telescope in…

Pulsar glitches are rapid spin-up events that occur in the rotation of neutron stars, providing a valuable probe into the physics of the interiors of these objects. Long-term monitoring of a large number of pulsars facilitates the detection…

Using large-scale parallel numerical simulations we explore spatiotemporal chaos in Rayleigh-B\'enard convection in a cylindrical domain with experimentally relevant boundary conditions. We use the variation of the spectrum of Lyapunov…

We study numerically chaotic behavior associated with a hyperbolic strange attractor of Plykin type in the model of Hunt, an artificially constructed dynamical system with continuous time. There are presented portraits of the attractor,…

Timing observations from the Parkes 64-m radio telescope for 165 pulsars between 1990 and 2011 have been searched for period glitches. A total of 107 glitches were identified in 36 pulsars, where 61 have previously been reported and 46 are…

Data are gathered from the Parkes pulsar data archive of twelve young radio pulsars, with the intervals of data for each pulsar ranged between 2.8 years and 6.8 years. 31 glitches are identified by using phase connection from "pulsar…