Observations of the 21 cm HI Line from the Milky Way galaxy using Pyramidal Horn Radio Telescope

Kaustav Bhattacharjee; Himanshu Grover; P. Arumugam

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arXiv · 2512.19262

Observations of the 21 cm HI Line from the Milky Way galaxy using Pyramidal Horn Radio Telescope

Kaustav Bhattacharjee·Himanshu Grover·P. Arumugam

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Abstract

We present the design, implementation, and operation of a pyramidal horn radio telescope built for detecting the Galactic 21 cm neutral hydrogen line emission. The system employs an SDR-based pipeline to obtain drift-scan observations, which were calibrated and processed to generate HI sky maps, a Galactic rotation curve and spiral arm features. This demonstrates that this low-cost system is effective both for educational purposes and scientific exploration of Galactic structure at radio frequencies.

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Kaustav Bhattacharjee, Himanshu Grover, P. Arumugam. 2025-12-22. Observations of the 21 cm HI Line from the Milky Way galaxy using Pyramidal Horn Radio Telescope. https://arxiv.org/abs/2512.19262

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