e-CALLISTO FITS Analyzer: A Software Framework for CALLISTO Solar Radio Data
G. L. S. S. Liyanage, J. Adassuriya, K. P. S. C. Jayaratne, C. Monstein, P. K. Manoharan
arXiv:2603.26086v3 Announce Type: replace
Abstract: Solar radio bursts are important signatures of dynamic processes in the solar corona, including particle acceleration and shock propagation associated with solar flares and coronal mass ejections. Among the missions that report solar radio bursts within 24 hours, the e-CALLISTO archive is the largest, with more than 150 stations worldwide. The archive generates large volumes of FITS data that are often affected by radio-frequency interference and background noise. Irregular frequency setups in different stations are also a limitation of statistical analysis of SRBs. Each CALLISTO observation is a 15-minute frame, which often causes a single burst to split over multiple frames, making event-level analysis difficult. This work presents the e-CALLISTO FITS Analyzer, a unified, interactive, cross-platform application for processing and analyzing e-CALLISTO dynamic spectra on Windows, macOS, and Linux. The application supports time and frequency merging to produce a continuous spectrum, applies mean background subtraction with user-controlled threshold clipping, and isolates burst regions through an interactive polygon mask in the time-frequency plane. It also extracts the maximum-intensity backbone, allows interactive outlier removal, and performs power-law fitting to estimate drift rates and derive shock height and speed using the Newkirk model, including $n$-fold scaling. For a Type II burst observed by Arecibo Observatory on 2 March 2022, the analyzer yielded an average drift rate of $-0.0400 pm 0.0003, MHz/s$ and an average shock speed of $449 pm 1, km/s$ at a height of $1.715 pm 0.002, R_{odot}$. The e-CALLISTO FITS Analyzer supports more reproducible, event-focused SRB analysis and improves access to physically meaningful measurements from e-CALLISTO FITS data.arXiv:2603.26086v3 Announce Type: replace
Abstract: Solar radio bursts are important signatures of dynamic processes in the solar corona, including particle acceleration and shock propagation associated with solar flares and coronal mass ejections. Among the missions that report solar radio bursts within 24 hours, the e-CALLISTO archive is the largest, with more than 150 stations worldwide. The archive generates large volumes of FITS data that are often affected by radio-frequency interference and background noise. Irregular frequency setups in different stations are also a limitation of statistical analysis of SRBs. Each CALLISTO observation is a 15-minute frame, which often causes a single burst to split over multiple frames, making event-level analysis difficult. This work presents the e-CALLISTO FITS Analyzer, a unified, interactive, cross-platform application for processing and analyzing e-CALLISTO dynamic spectra on Windows, macOS, and Linux. The application supports time and frequency merging to produce a continuous spectrum, applies mean background subtraction with user-controlled threshold clipping, and isolates burst regions through an interactive polygon mask in the time-frequency plane. It also extracts the maximum-intensity backbone, allows interactive outlier removal, and performs power-law fitting to estimate drift rates and derive shock height and speed using the Newkirk model, including $n$-fold scaling. For a Type II burst observed by Arecibo Observatory on 2 March 2022, the analyzer yielded an average drift rate of $-0.0400 pm 0.0003, MHz/s$ and an average shock speed of $449 pm 1, km/s$ at a height of $1.715 pm 0.002, R_{odot}$. The e-CALLISTO FITS Analyzer supports more reproducible, event-focused SRB analysis and improves access to physically meaningful measurements from e-CALLISTO FITS data.