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 bandwidths, 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. \r\n\r\nWe 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.