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arXiv · 2408.06682

Correlation-based Beam Calibration of 21cm Intensity Mapping

Jiacheng Ding·Xin Wang·Ue-Li Pen·Xiao-Dong Li
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Abstract

Foreground removal presents a significant obstacle in both current and forthcoming intensity mapping surveys. While numerous techniques have been developed that show promise in simulated datasets, their efficacy often diminishes when applied to real-world data. A primary issue is the frequency-dependent variations in the instrumental response. In this paper, we propose a novel approach utilizing the internal cross-correlation among different frequencies to calibrate the beam's frequency fluctuations. Using a simulated dataset that incorporates frequency-dependent random fluctuations into the beam model, we illustrate that our method can achieve considerable improvements over traditional techniques. Our results represent a step forward in enhancing the precision and reliability of foreground removal in intensity mapping surveys.

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Jiacheng Ding, Xin Wang, Ue-Li Pen, Xiao-Dong Li. 2024-08-13. Correlation-based Beam Calibration of 21cm Intensity Mapping. https://arxiv.org/abs/2408.06682

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