Parkes observations for project P972 semester 2018OCTS_04

50 years after the discovery of pulsars, these objects continue to push the boundaries in the testing of fundamental physics, most notably in General Relativity and in understanding the equation of state of cold, dense, nuclear matter. A number of pressing open questions remain, as basic as understanding pulsar orientation and radio beam geometry, and as complicated as understanding the plasma conditions that set their spectrum and degree of polarisation. Progress has mainly been limited by telescope sensitivity and simultaneous frequency coverage. The Parkes Ultra-Wideband receiver will change the game. We propose observations focused on a small group of bright pulsars to answer key questions on the pulsar emission process. We focus on three key observables, measured in individual pulses and average pulse profiles, across the widest available frequency range: the total power, the linear and circular polarisation, and the polarisation position angle profile across the pulse. The data will allow us to separate intrinsic emission properties from propagation effects in the pulsar magnetosphere and the interstellar medium, in a way that has never before been possible.

自脉冲星被发现以来的50年间，这类天体始终在推动基础物理检验的边界，尤以广义相对论（General Relativity）领域以及对冷密核物质物态方程的认知方面最为突出。当前仍存在诸多亟待解决的开放性问题，小至厘清脉冲星的取向与射电波束几何结构，大至解析决定其辐射谱与偏振程度的等离子体环境。研究进展长期受限于望远镜的灵敏度与同时覆盖的多频段范围。帕克斯超宽带（Parkes Ultra-Wideband）接收机将打破这一局限。我们提议针对一小批明亮脉冲星开展观测，以解答脉冲星辐射机制相关的核心科学问题。我们将在现有最宽的频率范围内，针对单脉冲与平均脉冲轮廓测量三项关键可观测物理量：总功率、线偏振与圆偏振，以及脉冲内的偏振位置角轮廓。该数据集将使我们得以通过前所未有的方式，将本征辐射特性与脉冲星磁层及星际介质中的传播效应分离开来。