Probing pulsar scattering between 120 and 280 MHz with the MWA

Abstract

The high sensitivity and wide frequency coverage of the Murchison Widefield Array allow for the measurement of the spectral scaling of the pulsar scattering timescale, $\alpha$, from a single observation. Here we present three case studies targeted at bright, strongly scattered pulsars J0534+2200 (the Crab pulsar), J0835-4510 (the Vela pulsar) and J0742-2822. We measure the scattering spectral indices to be $-3.8\pm 0.2$, $-4.0\pm 1.5$, and $-2.5\pm 0.6$ for the Crab, Vela, and J0742-2822, respectively. We find that the scattered profiles of both Vela and J0742-2822 are best described by a thin screen model where the Gum Nebula likely contributes most of the observed scattering delay. For the Crab pulsar we see characteristically different pulse shapes compared to higher frequencies, for which none of the scattering screen models we explore are found to be optimal. The presence of a finite inner scale to the turbulence can possibly explain some of the discrepancies.

14 pages, 8 figures, accepted for publication in ApJ

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Cited by in corpus (13)

• The Thousand-Pulsar-Array programme on MeerKAT -- V. Scattering analysis of single-component pulsars
• Science with the Murchison Widefield Array: Phase I Results and Phase II Opportunities
• The Southern-sky MWA Rapid Two-metre (SMART) pulsar survey -- I. Survey design and processing pipeline
• Scintillation can explain the spectral structure of the bright radio burst from SGR 1935+2154
• Spectral analysis of 22 radio pulsars using SKA-Low precursor stations
• MWA tied-array processing III: Microsecond time resolution via a polyphase synthesis filter
• A VOEvent based automatic trigger system for the Murchison Widefield Array
• NE2025: An Updated Electron Density Model for the Galactic Interstellar Medium
• Probing magneto-ionic microstructure towards the Vela pulsar using a prototype SKA-Low station
• Improving DM estimates using low-frequency scattering-broadening estimates
• Single-pulse analysis and average emission characteristics of PSR J1820-0427 from observations made with the MWA and uGMRT
• 50-250 MHz Pulsar Census with an SKA-Low prototype station: Spectra and Polarization
• Forecasting the FRB Population Observed Through Galaxy Cluster Lenses