Primary beam effects of radio astronomy antennas – II. Modelling MeerKAT L-band beams
Primary beam effects of radio astronomy antennas – II. Modelling MeerKAT L-band beams
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射电天文天线的主波束效应 – II. MeerKAT L 波段波束建模
DOI：
10.1093/mnras/stab104
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
S. Sirothia
中科院分区：
文献类型：
--
作者：
K. Asad;J. Girard;M. de Villiers;T. Ansah;K. Iheanetu;O. Smirnov;M. G. Santos;R. Lehmensiek;J. Jonas;D. I. L. de Villiers;K. Thorat;B. Hugo;S. Makhathini;G. Józsa;S. Sirothia
经过十年的设计和建造，南非的SKA-MID前体MeerKAT已经开始其科学运作。为了充分利用阵列的宽场能力，我们必须有一个准确的模型，其天线的主波束。我们已经使用了一个可用的L波段全偏振天文全息观测和电磁模拟创建稀疏表示的光束使用主成分和泽尔尼克多项式。空间系数的频谱行为已经使用离散余弦变换建模。我们已经在相关的软件工具中提供了直径为10度的基于Zernike的模型，该软件工具可用于方向相关的校准和成像。该模型对于梁琼斯矩阵的对角元素和较低频率更准确。随着我们在未来获得更精确的光束测量和模拟，特别是对于交叉偏振模式，我们的管道可以用于创建MeerKAT光束的更精确的稀疏表示。
After a decade of design and construction, South Africa's SKA-MID precursor MeerKAT has begun its science operations. To make full use of the widefield capability of the array, it is imperative that we have an accurate model of the primary beam of its antennas. We have used an available L-band full-polarization astro-holographic observation and electromagnetic simulation to create sparse representations of the beam using principal components and Zernike polynomials. The spectral behaviour of the spatial coefficients has been modelled using discrete cosine transform. We have provided the Zernike-based model over a diameter of 10 degrees in an associated software tool that can be useful for direction dependent calibration and imaging. The model is more accurate for the diagonal elements of the beam Jones matrix and at lower frequencies. As we get more accurate beam measurements and simulations in the future, especially for the cross-polarization patterns, our pipeline can be used to create more accurate sparse representations of MeerKAT beam.
影响因子：
6.5
作者：
van Haarlem, M. P.;Wise, M. W.;van Zwieten, J.
通讯作者：
van Zwieten, J.