Showing results for: [ Cordes, Jim ]
This proposal intends to confirm 10 candidate pulsars in a certain dispersion measures (DMs) range. Using new machine learning ranking and image processing methods, we have identified new candidates (... morewith relatively low dispersion measures) in the Parkes Multibeam Pulsar Survey (PMPS) data. The initial processing of the multibeam survey was so successful that relatively low S/N candidates were placed in a "tier 2" category and never followed-up for re-observation. We, therefore, expect that a large number of relatively weak pulsars with S/N ratios around 8 will later be identified as "real" pulsars. We have already shown, with previous observations, that two of our ranked candidates are pulsars that were missed by the previous processing of the survey and wish to carry out confirmation observation of the next ten of our top-ranked candidates. The new discoveries of low-DM pulsars will significantly improve our understanding of the nearby neutron star population, which may generate a gamma-ray background affecting all related experiments. Additionally, it will also improve our knowledge of the completeness of low DM pulsars in existing surveys, and in turn, help improve the design and performance of further pulsar search surveys. In the last round we were allocated 5 hours, but unfortunately, these were canceled because of the NASA Voyager Voyager tracking.less
Australia Telescope National Facility - P1012 - Confirming a Certain Dispersion Measures Range of Pulsar Candidates - Published 09 Oct 2019
Australia Telescope National Facility - P1012 - Confirming a Certain Dispersion Measures Range of Pulsar Candidates - Published 06 Oct 2019
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 19 bright pulsars that span the neutron star population, exhibit a diverse range of pulsar phenomenology. We request 32 hours of Parkes observation time to conduct simultaneous multi-frequency single-pulse observations for 16 pulsars. We will complement these with archival observations of three pulsars. 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 - P877 - Measuring the bandwidth of the pulsar emission mechanism - Published 09 May 2015
The relativistic binary pulsar J1906+0746
Australia Telescope National Facility - P510 - Timing and polarimetry of the relativistic
binary pulsar J1906+0746 - Published 11 Aug 2013
We request 9 regularly-spaced epochs to carry out high-precision
timing and polarimetry of PSR~J1906+0746, a new relativistic binary
pulsar discovered in the PALFA survey.
It is currently unclear whet... moreher the companion star to this young
144-ms pulsar is a white dwarf or another neutron star. The proposed
observations would measure at least two further post-Keplerian
parameters and determine the mass and inclination of the system.
In addition, they would allow us to measure the significant
profile variations expected due to relativistic spin-orbit coupling.
Given the exciting possibility of a second neutron star in this
system, we shall also use these observations carry out searches for
pulsations from the companion.less