Radio pulsar emission-beam geometry at low frequency: LOFAR High-Band Survey sources studied using Arecibo at 1.4 GHz and 327 MHz
Radio pulsar emission-beam geometry at low frequency: LOFAR High-Band Survey sources studied using Arecibo at 1.4 GHz and 327 MHz
复制标题
低频射电脉冲星发射波束几何形状：使用 Arecibo 在 1.4 GHz 和 327 MHz 下研究的 LOFAR 高频带勘测源
DOI：
10.1093/mnras/stac3613
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发表时间：
2023
影响因子：
4.8
通讯作者：
Olszanski, Timothy
中科院分区：
文献类型：
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作者：
Wahl, Haley;Rankin, Joanna;Venkataraman, Arun;Olszanski, Timothy
本文继续我们对射电脉冲星发射光束配置的研究，主要目的是将研究扩展到尽可能低的频率。在这里，我们重点关注一组最近发现的 133 颗脉冲星，其中大部分包含在 (100–200 MHz) LOFAR 高频带巡天中，由阿雷西博在 1.4 GHz 和 327 MHz 下观测到，还有一些在十米波长下观测到。我们的分析框架是核心/双锥束模型，我们抓住机会在概念上和定量上尽可能广泛地应用它，同时强调建模困难或可能违反其前提的情况。在绝大多数脉冲星中，确定了与核心/双锥模型一致的光束形式。此外，我们发现每个脉冲星的光束结构在可用频率范围内基本保持不变。当观察到轮廓变化时，它们可归因于不同的成分光谱，并且在某些情况下归因于不同的锥形光束尺寸。作为阿雷西博星群，许多或大部分天体往往落在银河系反中心区域和/或银河系高纬度地区，因此总的来说，它包括许多更近、更古老的脉冲星。我们在一些脉冲星中发现了许多有趣或不寻常的特征，这些特征将受益于进一步的研究。除了一些更靠近银河系内部的脉冲星外，该组遇到的散射水平较低到中等。
This paper continues our study of radio pulsar emission-beam configurations with the primary intent of extending study to the lowest possible frequencies. Here, we focus on a group of 133 more recently discovered pulsars, most of which were included in the (100–200 MHz) LOFAR High-Band Survey, observed with Arecibo at 1.4 GHz and 327 MHz, and some observed at decametre wavelengths. Our analysis framework is the core/double-cone beam model, and we took opportunity to apply it as widely as possible, both conceptually and quantitatively, while highlighting situations where modelling is difficult, or where its premises may be violated. In the great majority of pulsars, beam forms consistent with the core/double-cone model were identified. Moreover, we found that each pulsar’s beam structure remained largely constant over the frequency range available; where profile variations were observed, they were attributable to different component spectra and in some instances to varying conal beam sizes. As an Arecibo population, many or most of the objects tend to fall in the Galactic anticenter region and/or at high Galactic latitudes, so overall it includes a number of nearer, older pulsars. We found a number of interesting or unusual characteristics in some of the pulsars that would benefit from additional study. The scattering levels encountered for this group are low to moderate, apart from a few pulsars lying in directions more towards the inner Galaxy.