English
Related papers

Related papers: Ultra-High Resolution Intensity Statistics of a Sc…

200 papers

We present results for the photon spectrum emitted in non-linear Compton scattering of pulsed ultra-strong laser fields off relativistic electrons for intensities up to $a_0\gtrsim 100$ and pulse lengths of a few laser cycles. At ultrahigh…

High Energy Physics - Phenomenology · Physics 2025-05-08 D. Seipt , B. Kampfer

We conducted radio interferometric observations of six pulsars at 610 MHz using the Giant Metrewave Radio Telescope (GMRT). All these objects were claimed or suspected to be the gigahertz-peaked spectra (GPS) pulsars. For a half of the…

High Energy Astrophysical Phenomena · Physics 2015-06-24 M. Dembska , R. Basu , J. Kijak , W. Lewandowski

We report on findings from scintillation analyses using high-cadence observations of eight canonical pulsars with observing baselines ranging from one to three years. We obtain scintillation bandwidth and timescale measurements for all…

Dynamic scattering and imaging with coherent, ultrafast, extreme ultraviolet (EUV) light sources can resolve charge, phonon and spin processes on their intrinsic length and time scales. However, full field coherent diffraction imaging…

At radio wavelengths, scattering in the interstellar medium distorts the appearance of astronomical sources. Averaged over a scattering ensemble, the result is a blurred image of the source. However, Narayan & Goodman (1989) and Goodman &…

Instrumentation and Methods for Astrophysics · Physics 2016-01-19 Michael D. Johnson , Carl R. Gwinn

The increasing interest in FLASH-RT has lead to the conversion of linear accelerators to enable ultra-high dose rate (UHDR) beams for preclinical research. Dosimetry hereof remains challenging with several crucial aspects missing. This work…

Understanding the jitter noise resulting from single-pulse phase and shape variations is important for the detection of gravitational waves using pulsar timing array. We presented measurements of jitter noise and single-pulse variability of…

High Energy Astrophysical Phenomena · Physics 2024-01-24 S. Q. Wang , N. Wang , J. B. Wang , G. Hobbs , H. Xu , B. J. Wang , S. Dai , S. J. Dang , D. Li , Y. Feng , C. M. Zhang

We examine the effect of Galactic diffractive interstellar scintillation as a means of explaining the reported deficit of Fast Radio Burst (FRB) detections at low Galactic latitude. We model the unknown underlying FRB flux density…

High Energy Astrophysical Phenomena · Physics 2015-05-25 Jean-Pierre Macquart , Simon Johnston

This paper presents an investigation of spectral properties of 10 millisecond pulsars (MSPs) discovered by the uGMRT, observed from 2017-2023 using band 3 (300-500 MHz) and 4 (550-750 MHz) of uGMRT. For these MSPs, we have reported a range…

High Energy Astrophysical Phenomena · Physics 2024-08-15 Rahul Sharan , Bhaswati Bhattacharyya , Sangita Kumari , Jayanta Roy , Ankita Ghosh

We introduce a novel analysis technique for pulsar secondary spectra. The power spectrum of pulsar scintillation (referred to as the "secondary spectrum") shows differential delays and Doppler shifts due to interference from multi-path…

Instrumentation and Methods for Astrophysics · Physics 2020-12-02 Tim Sprenger , Olaf Wucknitz , Robert Main , Daniel Baker , Walter Brisken

Single pulses preserve information about the pulsar radio emission and propagation in the pulsar magnetosphere, and understanding the behaviour of their variability is essential for estimating the fundamental limit on the achievable pulsar…

High Energy Astrophysical Phenomena · Physics 2016-09-21 K. Liu , C. G. Bassa , G. H. Janssen , R. Karuppusamy , J. McKee , M. Kramer , K. J. Lee , D. Perrodin , M. Purver , S. Sanidas , R. Smits , B. W. Stappers , P. Weltevrede , W. W. Zhu

In this paper, we consider random phase fluctuations imposed during wave propagation through a turbulent plasma (e.g. ionosphere) as a source of additional noise in interferometric visibilities. We derive expressions for visibility variance…

Instrumentation and Methods for Astrophysics · Physics 2015-12-02 H. K. Vedantham , L. V. E. Koopmans

A method is shown for preventing temporal broadening of ultrafast optical pulses in highly dispersive and fluctuating media for arbitrary signal-pulse profiles. Pulse pairs, consisting of a strong-field control-pulse and a weak-field…

Optics · Physics 2021-11-17 Haider Zia

The basic form of drifting sub-pulses is that of a periodicity whose phase depends (approximately linearly) on both pulse longitude and pulse number. As such, we argue that the two-dimensional Fourier transform of the longitude-time data…

Astrophysics · Physics 2009-11-07 R. T. Edwards , B. W. Stappers

We report the detection of pulse-to-pulse periodic intensity modulations, in observations of recycled pulsars. Even though the detection of individual pulses was generally not possible due to their low flux density and short duration,…

Astrophysics · Physics 2009-11-07 R. T. Edwards , B. W. Stappers

We present a new analytical solution for the equation of motion of relativistic electrons in the focus of a high-intensity laser pulse. We approximate the electron's transverse dynamics in the averaged field of a long laser pulse focused to…

Young pulsars deviate from a perfectly regular spin-down by two non-deterministic phenomena: impulsive glitches and timing noise. Both phenomena are interesting per se, and may provide insights into the superfluid properties of neutron…

High Energy Astrophysical Phenomena · Physics 2023-02-17 Marco Antonelli , Avishek Basu , Brynmor Haskell

We have searched 92 unidentified sources from the FIRST and NVSS 1400 MHz radio survey catalogs for radio pulsations at 610 MHz. The selected radio sources are bright, have no identification with extragalactic objects, are point-like and…

Astrophysics · Physics 2008-11-26 Fronefield Crawford , Victoria M. Kaspi , Jon F. Bell

We present the detection of 107 pulsars with interstellar scintillation arcs at 856--1712\,MHz, observed with the MeerKAT Thousand Pulsar Array Programme. Scintillation arcs appear to be ubiquitous in clean, high S/N observations, their…

High Energy Astrophysical Phenomena · Physics 2022-11-17 R. A. Main , A. Parthasarathy , S. Johnston , A. Karastergiou , A. Basu , A. D. Cameron , M. J. Keith , L. S. Oswald , B. Posselt , D. J. Reardon , X. Song , P. Weltevrede

The observed spectra of 9 pulsars for which multiwavelength data are available from radio to $X$- or $\gamma$-ray bands (Crab, Vela, Geminga, B0656+14, B1055-52, B1509-58, B1706-44, B1929+10, and B1951+32) are compared with the spectrum of…

Astrophysics of Galaxies · Physics 2009-08-11 H. Ardavan , A. Ardavan , J. Singleton , J. Fasel , W. Junor , J. Middleditch , M. R. Perez , A. Schmidt , P. Sengupta , P. Volegov
‹ Prev 1 8 9 10 Next ›