Parkes observations for project P1011 semester 2019APRS_11

Pulsars with features in their radio spectra, such as curvature or breaks seem to be special cases among the known pulsar population, with only about 20 per cent exhibiting them. Unfortunately, reliable flux density measurements besides at 1.4 GHz are often unavailable, so that their spectral morphologies and features cannot be determined accurately. We propose to utilize the unique capabilities of the newly commissioned UWL receiver at the Parkes telescope, its extremely wide instantaneous frequency coverage from about 700 to 4000 MHz together with its high sensitivity, to determine the spectra of 26 radio pulsars. These have previously been identified to exhibit spectral features or show hints thereof. The new Parkes data are crucial to determine their spectral morphologies in that frequency range, to characterize their spectral features and to resolve these within the recorded bandwidth. Our aim is to understand the physical origin of the features, namely, whether these are perhaps intrinsic to the pulsar emission in these sources, are caused by absorption processes inside the pulsar's magnetosphere, or along the line of sight.

在已知脉冲星群体中，射电谱具有曲率或断点等特征的脉冲星似乎属于特殊情况，仅约20%的脉冲星表现出此类特征。遗憾的是，除1.4 GHz外，可靠的流量密度测量数据往往难以获取，因此无法准确确定其谱形态与特征。我们提议利用帕克斯望远镜新投入使用的UWL接收器的独特性能——其约700至4000 MHz的极宽瞬时频率覆盖范围及高灵敏度——来测定26颗射电脉冲星的光谱。这些脉冲星此前已被确认具有谱特征或显示出相关迹象。新的帕克斯数据对于确定该频率范围内的谱形态、表征其谱特征以及在记录带宽内解析这些特征至关重要。我们的目标是理解这些特征的物理起源，即它们是否可能是这些源中脉冲星辐射固有的，或是由脉冲星磁层内部或视线方向上的吸收过程所导致。