Showing results for: [ Tremblay, Steven ]
The paucity of known intermittent pulsars makes individual studies valuable from the perspective of understanding how these pulsars emit and how that emission is changing in time and as a function of ... morefrequency. The inherent difficulty in detecting these objects implies that their small population may well simply be a sampling bias, thus studying individual examples in details is fundamentally important in developing a complete understanding of the Galactic population. The Ultra-Wide-Band receiver and the MEDUSA backend provide unprecedented frequency coverage and will allow us to study the emission of the intermittent pulsar J1107-5907 in great detail. In particular, we will focus on the spectral characteristics of the emission, the frequency dependence of emission rates and the time scales on which the emission state switching occurs. By constraining the intermittency time scales we will be able to comment on model predictions, while the spectral index analysis will provide insights into the emission mechanism itself.less
Australia Telescope National Facility - P1013 - An ultra-wide-band study of the intermittent pulsar J1107-5907 - Published 10 Oct 2019
Australia Telescope National Facility - P1013 - An ultra-wide-band study of the intermittent pulsar J1107-5907 - Published 07 Jul 2019
Australia Telescope National Facility - P1013 - An ultra-wide-band study of the intermittent pulsar J1107-5907 - Published 06 Jul 2019
Australia Telescope National Facility - P1013 - An ultra-wide-band study of the intermittent pulsar J1107-5907 - Published 04 Jul 2019
Australia Telescope National Facility - P1013 - An ultra-wide-band study of the intermittent pulsar J1107-5907 - Published 03 Jul 2019
More than four decades since their discovery, the physics governing the emission of radio waves from pulsars remains poorly understood. Their rich and diverse emission phenomenology on very short time... more scales, coupled with the complexity in observed polarisation, poses considerable challenges to both theorists and observers alike. Of the multitude of emission phenomena, sub- pulse drifting---manifesting as organised sub-structures marching in phase within the emission window---is considered to be the most promising avenue for nailing down the underlying physics. In this proposal, we seek a modest 10 hr of Parkes time to undertake high-time resolution observations of a carefully selected sample of pulsars that are known to show interesting drifting behaviour. We will coordinate with the MWA for simultaneous low-frequency coverage, which will enable the sampling of pulsar magnetospheres over a wide range of emission heights, made possible by the 1:10 frequency coverage of the combined use of Parkes and the MWA. The success of this project will mark a major step toward our eventual goal of a three-dimensional reconstruction (tomography) of pulsar emission geometries.less
Australia Telescope National Facility - P920 - Chasing pulsar emission mechanism via sub-pulse drifting - Published 26 Oct 2016
While pulsars are well known to emit over a wide range of frequencies, the total bandwidth over which the emission is correlated and the pulse-to-pulse variability of this bandwidth are poorly underst... moreood. Given this uncertainty, it is unsurprising that the effects of this variability on precision pulsar timing are unknown. We therefore propose to answer three questions about the broadband nature of pulsar emission:
1) Over what bandwidths are individual pulses correlated?
2) Does this bandwidth vary across the pulsar population?
and 3) How does this bandwidth affect pulsar timing?
To answer these questions, we propose to study 5 bright pulsars that span the neutron star population, exhibit a diverse range of pulsar phenomenology. We request 5 hours of Parkes observation time to conduct simultaneous multi-frequency single-pulse observations jointly with the MWA These measurements will be used to construct better empirical models for pulsar emission, test theoretical predictions, and assess the effects of broadband variability on pulsar timing measurements.less
Australia Telescope National Facility - P896 - Wide-band pulsar emission studies using simultaneous observations with Parkes and the MWA - Published 25 May 2016