First Light for the New 30 m Parabolic Radio Telescope at ArQi: Implications for Space Weather Monitoring

Interplanetary scintillation (IPS) phenomenon behaves as twinkling of a compact radio source due to scattering in the solar wind. Here we report the first identification of IPS signal by a new parabolic dish antenna with its diameter of 30 m, observed on 2024 March 1. The radio source of 3C446 at solar elongation of 6.4° was targeted during its 5 minute transit across our antenna beam at ArQi (115.13°E, 44.73°N). Our receiver is characterized as simultaneous measurements of dual polarizations from 3C446 emission, integrated over a 40 MHz bandwidth around its central frequency of 1.4 GHz. The horizontally and vertically polarized components, though independently and simultaneously measured, show a strong correlation in terms of both time-series and power spectral analyses. Using a spectra-fitting method on basis of the classic IPS theory, the solar wind speed in our observation case is inferred to be 283 km s⁻¹. Such a solar wind speed inferred at the piercing point of 24 solar radii along our IPS ray-path reaffirms the interplanetary diagnostic capability of ground-based IPS technique. Our first-light IPS observation at ArQi represents a significant advance in the ongoing commissioning phase of our IPS-dedicated telescope facility within the Chinese Meridian Project-Phase II.