Click here to view this collection in the new DAP user interface
Parkes observations for project P992 semester 2018OCTS_01
Relativistic binary pulsars allow for a multitude of important scientific applications through the process of high-precision pulsar timing, including some of the most constraining tests of gravitational theories ever conducted. However, known technical challenges exist in the process of timing relativistic binary pulsars across large observing band... morewidths, which can interfere with these precise measurements. These include apparent chromatic orbital effects (ACOEs), which cause an apparent change in the pulsar's dispersion measure as a function of orbital phase, and `periastron wobbles' caused by incorrect modeling of the pulsar's binary motion during phases of extreme acceleration and jerk. As these effects are more prominent across wide observing bandwidths, correcting them in the newly-commissioned UWL is a critical step in ensuring its ability to perform accurate high-precision timing of relativistic binary pulsars in the future.
We propose a limited set of observations on the relativistic binary PSR J1757-1854, which displays some of the most extreme orbital properties ever seen in a relativistic pulsar binary. These observations, intended to span 2 consecutive orbits of the pulsar, will be used to ensure that the UWL (and its backend Medusa) are able to correctly process the data from extreme relativistic binary systems, will help to resolve the lingering problem of ACOEs in pulsar data-processing software packages, and will serve the secondary purpose of characterirsing the properties of this binary system over a wide bandwidth for the first time. less
Astronomical and Space Sciences not elsewhere classified
01 Oct 2018
01 Apr 2019
compact binaries and/or black-holes
Creative Commons Attribution 4.0 International Licence
Cameron, Andrew; Kramer, Michael; Hobbs, George; Freire, Paulo; Champion, David; Wex, Norbert (2018): Parkes observations for project P992 semester 2018OCTS_01. v1. CSIRO. Data Collection.
All Rights (including copyright) CSIRO 2018.
Access to this collection's metadata and/or files (if any) are restricted until 01 Oct 2020.
Australia Telescope National Facility
P992 - Exploratory observations of a relativistic binary pulsar with an ultra-wideband receiver.
Parkes is currently observing PSR J1757-1854, a pulsar which spins once every 21.5 milliseconds. Pulsars, rapidly-rotating neutron stars, are some of the densest and fastest-spinning objects in the known universe, and studies of them can provide a large number of exciting scientific results. This particular pulsar is in orbit around another (non-pu... morelsing) neutron star, and its orbit (which lasts only 4.4 hours) is one of the most extreme ever discovered, reaching accelerations of up to 680 m/s/s. This kind of pulsar, known as a "relativistic binary pulsar", can be extremely useful in studying different theories of gravity (like Einstein's Theory of General Relativity) under extreme conditions that cannot be produced here on Earth.
This observing project serves two purposes. The first is to study this binary pulsar using the new Ultra-Wideband receiver (UWL), which can detect radio signals between 0.7 and 4 GHz in frequency, and learn how its properties change as a function of frequency. However, the more important goal is to test that the UWL receiver can correctly observe a pulsar which displays such extreme behaviour, so that it can conduct studies of even more extreme binary systems in the future. Making sure that the UWL is working correctly under lots of different extreme situations is critically important in making sure that Parkes delivers the best scientific results possible. less