Description
Fast radio bursts (FRBs) are powerful ms blasts of celestial origin detected only at radio frequencies. Since their discovery in 2007, about $800$ FRB have been found.FRBs come from cosmological distances (within redshift $z \sim 1$) and present kJy flux densities. Due to these properties and brightness temperatures $T_{\rm B}>10^{36}$ K, most FRB progenitor models invoke coherent emission mechanisms in strongly magnetised neutron stars (magnetars). The vast majority of FRBs are one-off events, but a fraction ($\sim 8.5\%$) are observed to repeat, excluding catastrophic events as their origin. Repeating FRBs are of particular interest, since they can be monitored over time and localised with precision. Long-term monitorings of repeating FRBs are key also to shed light on their activity patterns, the spectral and polarimetric properties of the bursts, and energetic distribution. We are studying a sample of repeating FRBs, including the newly discovered and very active FRB\,20240114A located at redshift z $\sim 0.42$, using the high-sensitivity Northern Cross transit telescope and the 32-m parabolic dish in Medicina, near Bologna, and the 32-m dish in Noto, Sicily. Given the large data sets, the thousands of FRB candidate signals, and the presence of strong radio frequency interferences (RFIs), we implemented for each antenna a new pipeline based on RFI mitigation tools, a transient detection algorithm, and a machine learning classification of the bursts with 11 neural network models. Furthermore, we are carrying through a monitoring of a number of Galactic magnetars to search for possible FRB-like events, which would confirm their link with FRBs.
