Scattering features and variability of the Crab pulsar

Abstract

We report on Westerbork Synthesis Radio Telescope observations of the Crab pulsar at 350 MHz from 2012 November 24 until 2015 June 21. During this period we consistently observe variations in the pulse profile of the Crab. Both variations in the scattering width of the pulse profile as well as delayed copies, also known as echoes, are seen regularly. These observations support the classification of two types of echoes: those that follow the truncated exponential shape expected for the thin-screen scattering approximation, and echoes that show a smoother, more Gaussian shape. During a sequence of high-cadence observations in 2015, we find that these non-exponential echoes evolve in time by approaching the main pulse and interpulse in phase, overlapping the main pulse and interpulse, and later receding. We find a pulse scatter-broadening time scale, $\tau$, scaling with frequency as ${\nu }^{\alpha }$, with $\alpha =-3.9\pm 0.5$, which is consistent with expected values for thin-screen scattering models

arXiv comment10 pages, 7 figures

References in corpus (17)

• PSRCHIVE and PSRFITS An Open Approach to Radio Pulsar Data Storage and Analysis
• DSPSR: Digital Signal Processing Software for Pulsar Astronomy
• Multifrequency Radio Observations of the Crab Pulsar
• The Gaussian Plasma Lens in Astrophysics. Refraction
• A Precise Proper Motion for the Crab Pulsar, and the Difficulty of Testing Spin-Kick Alignment for Young Neutron Stars
• Evolution of the Magnetic Field Structure of the Crab Pulsar
• The dust and gas content of the Crab Nebula
• Giant pulses from the Crab pulsar: A wide-band study
• PuMaII: A wide band pulsar machine for the WSRT
• A Plasma Prism Model for an Anomalous Dispersion Event in the Crab Pulsar
• Correlation of the scattering and dispersion events in the Crab Nebula pulsar
• The Analytical Solution to the Temporal Broadening of a Gaussian-Shaped Radio Pulse by Multipath Scattering from a Thin Screen in the Interstellar Medium
• Multi-frequency scatter broadening evolution of pulsars - I
• The frequency dependence of scattering imprints on pulsar observations
• The study of multi-frequency scattering of ten radio pulsars
• The 1997 event in the Crab pulsar revisited
• Low-frequency pulse profile variation in PSR B2217+47: evidence for echoes from the interstellar medium

Cited by in corpus (11)

• LOFAR Detection of 110-188 MHz Emission and Frequency-Dependent Activity from FRB 20180916B
• The NANOGrav 12.5-year Data Set: Wideband Timing of 47 Millisecond Pulsars
• The CHIME Pulsar Project: System Overview
• A burst storm from the repeating FRB 20200120E in an M81 globular cluster
• Resolving the emission regions of the Crab pulsar's giant pulses
• Resolving the Emission Regions of the Crab Pulsar's Giant Pulses II. Evidence for Relativistic Motion
• Kinematics of Crab Giant Pulses
• Scintillation can explain the spectral structure of the bright radio burst from SGR 1935+2154
• First Results from the REAL-time Transient Acquisition backend (REALTA) at the Irish LOFAR station
• Constraining the FRB mechanism from scintillation in the host galaxy
• A search for radio pulsars in five nearby supernova remnants