相关论文: Could the pulsars actually be oscillators?
Luminosity is an intrinsic property of radio pulsars related to the properties of the magnetospheric plasma and the beam geometry, and inversely proportional to the observing frequency. In traditional models, luminosity has been considered…
An anharmonic oscillator when driven with a fast, frequency chirped voltage pulse can oscillate with either small or large amplitude depending on whether the drive voltage is below or above a critical value-a well studied classical…
The following results of dissertation are submitted for defense: 1. Precise measurements of coordinates and proper motion of the pulsar PSR 0329+54 using the VLBI method. 2. Establishing of the reason for the discrepancy between the…
We study a Schrodinger particle in an infinite spherical well with an oscillating wall. Parametric resonances emerge when the oscillation frequency is equal to the energy difference between two eigenstates of the static cavity. Whereas an…
The behavior of coupled harmonic oscillators in systems with specified boundary conditions is typically characterized by resonances whose frequency spectra represent harmonics according to properties of the individual oscillators, the…
Pulsar timing array projects are carrying out high precision observations of millisecond pulsars with the aim of detecting ultra-low frequency (~ 10^{-9} to 10^{-8} Hz) gravitational waves. We show how unambiguous detections of such waves…
When rotation is not taken into account, the measurement of the Gravitational Redshift can provide unique information about the compactness ($M/R$) of the star. Rotation alters the gravitational redshift rendering thereby a unique…
Linearised relativistic elasticity equations of motion are considered for a rod and a spinning ring encountering a gravitational wave. In the case of the rod, the equations reduce to a wave equation with appropriate boundary conditions.…
The number of known millisecond pulsars has dramatically increased in the last few years. Regular observations of these pulsars may allow gravitational waves with frequencies ~10^-9 Hz to be detected. A ``pulsar timing array'' is therefore…
The present work investigates the numerical evolution of linearized oscillations of non-rotating, spherically symmetric neutron stars within the framework of general relativity. We derive the appropriate equations using the (3+1)-formalism.…
We investigate the generation of gravitational waves from the rotation of an orthogonal pulsar magnetosphere in flat space time. We calculate the first order metric perturbation due to the rotation of the non-axisymmetric distribution of…
Gravitational waves are tiny disturbances in space-time and are a fundamental, although not yet directly confirmed, prediction of General Relativity. Rapidly rotating neutron stars are one of the possible sources of gravitational radiation…
Non radial oscillations of neutron stars are associated with the emission of gravitational waves. The characteristic frequencies of these oscillations can be computed using the theory of stellar perturbations, and they are shown to carry…
Radio pulsars are fascinating and extremely useful objects. Despite our on-going difficulties in understanding the details of their emission physics, they can be used as precise cosmic clocks in a wide-range of experiments -- in particular…
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…
Observations of short-duration gamma-ray bursts and their afterglows show that a good fraction (perhaps $\gtrsim50\%$) of binary neutron star mergers lead to strongly magnetized, rapidly rotating pulsars (including millisecond magnetars),…
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…
A monochromatic linear source of light is rotated with certain angular frequency and when such light is analysed after reflection then a change of frequency or wavelength may be observed depending on the location of the observer. This…
A photon emitted near a compact object at an angle $\alpha$ with respect to the radial direction escapes to infinity at a different angle $\psi>\alpha$. This bending of light is caused by a strong gravitational field. We show that, in a…
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…