English
Related papers

Related papers: Scattering analysis of LOFAR pulsar observations

200 papers

Observations reveal a uniform Kolmogorov turbulence throughout the diffuse ionized interstellar medium (ISM) and supersonic turbulence preferentially located in the Galactic plane. Correspondingly, we consider the Galactic distribution of…

Astrophysics of Galaxies · Physics 2017-01-25 Siyao Xu , Bing Zhang

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…

Astrophysics · Physics 2009-11-13 Simon Johnston , Aris Karastergiou , Dipanjan Mitra , Yashwant Gupta

We present a study of the spectral properties of 441 pulsars observed with the Parkes radio telescope near the centre frequencies of 728, 1382 and 3100 MHz. The observations at 728 and 3100 MHz were conducted simultaneously using the…

High Energy Astrophysical Phenomena · Physics 2018-03-30 F. Jankowski , W. van Straten , E. F. Keane , M. Bailes , E. Barr , S. Johnston , M. Kerr

We analyse the stochastic properties of the 49 pulsars that comprise the first International Pulsar Timing Array (IPTA) data release. We use Bayesian methodology, performing model selection to determine the optimal description of the…

The parabolic arc phenomenon visible in the Fourier analysis of the scintillation spectra of pulsars provides a new method of investigating the small scale structure in the ionized interstellar medium (ISM). We report archival observations…

Astrophysics · Physics 2011-02-11 Frank S. Trang , Barney J. Rickett

In an earlier paper (Ahuja, et al, 2005), based on simultaneous multi-frequency observations with the Giant Metrewave Radio Telescope (GMRT), we reported the variation of pulsar dispersion measures (DMs) with frequency. A few different…

Astrophysics · Physics 2008-11-26 Amrit Lal Ahuja , Dipanjan Mitra , Yashwant Gupta

Light travel time changes due to gravitational waves may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is…

Instrumentation and Methods for Astrophysics · Physics 2015-12-16 Nipuni Palliyaguru , Daniel Stinebring , Maura McLaughlin , Paul Demorest , Glenn Jones

We consider the problem of fixed frequency acoustic scattering from a sound-soft flat screen. More precisely the obstacle is restricted to a two-dimensional plane and interacting with a arbitrary incident wave, it scatters acoustic waves to…

Analysis of PDEs · Mathematics 2020-07-20 Emilia Blåsten , Lassi Päivärinta , Sadia Sadique

We present a large survey of giant pulses from the Crab Pulsar as observed with the first station of the Long Wavelength Array. Automated methods for detecting giant pulses at low frequencies where scattering becomes prevalent are also…

Solar and Stellar Astrophysics · Physics 2016-10-05 T. Eftekhari , K. Stovall , J. Dowell , F. K. Schinzel , G. B. Taylor

A pulsar's scintillation bandwidth is inversely proportional to the scattering delay, making accurate measurements of scintillation bandwidth critical to characterize unmitigated delays in efforts to measure low-frequency gravitational…

Broadband radio waves emitted from pulsars are distorted and delayed as they propagate toward the Earth due to interactions with the free electrons that compose the interstellar medium, with lower radio frequencies being more impacted than…

High Energy Astrophysical Phenomena · Physics 2023-06-12 Olivia Young , Michael Lam

In this work we study variations in the parabolic scintillation arcs of the binary millisecond pulsar PSR J1643-1224 over five years using the Large European Array for Pulsars (LEAP). The 2D power spectrum of scintillation, called the…

The pulse widths, dispersion measures and dispersion indices of Fast Radio Bursts (FRB) impose coupled constraints that all models must satisfy. We show that if the dispersion measures resulted from propagation through the intergalactic…

High Energy Astrophysical Phenomena · Physics 2015-01-07 J. I. Katz

The shapes of pulse profiles, especially their variations with respect to observing frequencies, are very important to understand emission mechanisms of pulsars, while no previous attempt has been made in interpreting the complicated…

Astrophysics · Physics 2009-11-07 G. J. Qiao , J. F. Liu , B. Zhang , J. L. Han

Low-frequency gravitational-wave experiments require the highest timing precision from an array of the most stable millisecond pulsars. Several known sources of noise on short timescales in single radio-pulsar observations are well…

We describe how the observed polarization properties of an astronomical object are related to its intrinsic polarization properties and the finite temporal and spectral resolutions of the observing device. Moreover, we discuss the effect…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Paz Beniamini , Pawan Kumar , Ramesh Narayan

We analyze the frequency dependence of the dispersion measure (DM), the column density of free electrons to a pulsar, caused by multipath scattering from small scale electron-density fluctuations. The DM is slightly different along each…

Instrumentation and Methods for Astrophysics · Physics 2016-01-21 J. M. Cordes , R. M. Shannon , D. R. Stinebring

The Main Aim of this paper is to explain the emergence of new components of pulsars at higher radio bands by implementing the Inverse Compton Scattering Mechanism. From pulsar radio observation, it is seen that a couple of pulsars reveal…

High Energy Astrophysical Phenomena · Physics 2026-01-19 Tridib Roy , Mayuresh Surnis , Mageshwaran Tamilan , Monalisa Halder , Siddhartha Biswas

Nonlinear radio waves modulate the plasma, scatter on the modulations, and develop an intermittent power spectrum -- perhaps. Rudiments of theory, numerical simulations, and qualitative modeling of nonlinear scattering are presented.…

High Energy Astrophysical Phenomena · Physics 2020-02-10 Andrei Gruzinov

Intensity scintillations of radio pulsars are known to originate from interference between waves scattered by the electron density irregularities of interstellar plasma, often leading to parabolic arcs in the two-dimensional power spectrum…

‹ Prev 1 4 5 6 7 8 10 Next ›