Radioheliographs and wideband photo voltaic radio spectrographs are important elements of the Chinese language Meridian Undertaking (CMP)‐II (C. Wang et al., 2024) that goals to observe the entire photo voltaic‐terrestrial chain of house climate occasions, from the decrease photo voltaic ambiance to close‐Earth house. This work introduce the CMP‐II radio devices, together with the MUSER‐L/I/H, the tremendous‐wideband spectrographs of Mingantu and Chashan stations overlaying the wideband vary of 30 MHz–15 GHz. The general design, some technical particulars, the calibration technique, and efficiency with some preliminary information of those devices are introduced.
Determine 1. The panorama view of Mingantu Observing Station with MUSER‐H/I/L. arrays, calibration antennas.
The photo voltaic radio imaging spectroscopic devices embrace a Meter–Decameter Wavelength Radioheliograph (30–400 MHz), the extension of MUSER to decrease frequency vary, a Round Array Photo voltaic Radio Telescope (150–450 MHz) at Daocheng in Sichuan province (DART, J. Yan et al., 2023), and incorporate MUSER (Y. Yan et al., 2021), a Centimeter‐Decimeter Wavelength Radioheliograph (400 MHz–15 GHz) with new calibration system. The photo voltaic radio spectrometers embrace a Metric Wavelength Photo voltaic Radio Spectrometer (90–600 MHz) at Chashan in Shandong province (Chang et al., 2024), Decameter‐Metric to Centimetric Wavelength Photo voltaic Radio Spectrometers (30–400 MHz, 400 MHz–2 GHz, 2–15 GHz) at MUSER website, providing spectrum monitoring means throughout a brilliant vast band from 30 MHz as much as 15 GHz. The tremendous‐high quality spectral constructions of metric photo voltaic radio bursts are anticipated to be recorded. The info can be used to advance understanding of electron acceleration and emission mechanisms, and to enhance early warnings of CME shocks and photo voltaic energetic particles. Determine 1 exhibits a panorama view of MUSER arrays and calibration antennas, and so forth., within the Mingantu Observing Station.
Determine 2. A burst occasion on 6 January 2025. (a) The LASCO/SOHO picture at 05:06 UT. (b) The MUSER‐L multi‐frequencyimages in 30 MHz∼400 MHz at 05:07 UT. The inserted dynamic spectrum ranging from 05:06 UT displaying the enhancedsolar radio bursts.
With the newly established calibration methods for MUSER below CMP‐II and the brand new calibration technique, additional progress on photo voltaic radio imaging spectroscopy has been made. Varied photo voltaic radio bursts have been recorded by MUSER‐L/‐I/‐H and Mingantu spectrometers. Knowledge are transmitted to the CMP information middle each day. A photo voltaic radio burst occasion occurred on 6 January 2025 and noticed by MUSER‐L. The multi‐frequency photos in 30 MHz – 400 MHz vary have been obtained and the radio supply at 30 MHz was so far as over 10 photo voltaic radius. The multi‐frequency photos in 30 MHz – 400 MHz vary exhibit beam‐like cone construction with excessive frequency sources confined to the decrease altitude near the Solar, as proven in Determine 2. The alignment of those multi‐frequency radio sources at 05:07 UT agrees with the intense construction as proven by SOHO/LASCO C2 picture across the identical time interval 05:06 UT. This occasion demonstrates the capability to observe photo voltaic eruptions from the Solar into interplanetary house.
The Chashan Broadband Photo voltaic radio spectrometer with excessive temporal‐spectral resolutions (<1 ms, 100 kHz) at meter wavelengths overlaying 90–600 MHz has been developed (CBSm, Chang et al., 2024). The most important scientific goal of CBSm is to report superfine spectral constructions of metric photo voltaic radio bursts. See Determine 3 for examples of such spectral high quality constructions recorded by CBSm. Since 10 November 2022, CBSm has detected many photo voltaic radio bursts, together with week‐lengthy Kind I bursts/noise storms, 50 Kind II bursts, a number of thousand Kind III bursts, and 20 Kind IV bursts.
Determine 3. Prime left panel is Chashan Photo voltaic Radio Spectrometer. (a) An instance of stripes with an total wavy morphology within the 8 Could 2024 occasion, with beaded construction rising within the center portion (tailored from C. Li et al., 2025). (b) Kind II bursts from 00:26:30 UT to 00:29:30 UT on 18 December 2023. (c) A sort II burst from 07:50:00 UT to 08:00:00 UT on 5 February 2025.(d) Kind III bursts from 23:29:00 UT to 23:30:00 UT on 18 March 2023. (e) Polarization diploma comparable to (d).
The info introduced on this paper can be found from the Nationwide Area Science Knowledge Heart for the Chinese language Meridian Undertaking (https://information.meridianproject.ac.cn). Some information could also be topic to a proprietary interval; please seek advice from the info middle’s entry coverage. MUSER occasion information may be visited at http://120.193.217.157:5404/solar_event_database/. Native MUSER‐L information may be browsed at http://120.193.217.157:5403/muser/MUSER‐L/, and CBSm information units may be accessed at http://47.104.87.104/SRData/CBSm/.
Conclusions
The amenities described right here supply uniquely broad frequency protection and superior imaging and spectral functionality. Their open information coverage will allow collaborative analysis and improve world house climate monitoring and forecasting.
More information: The nugget relies on the lately printed paper by Yihua Yan et al., 2025, Area Climate（open entry）, DOI:10.1029/2025SW004595
References
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