Sub-GHz Radio Pulsar Emission - Lessons Learned and Predictions for SKA

Neutron stars observed as radio pulsars are one of the prime astrophysical laboratories that allow us to test the laws of nature in extreme environments inaccessible on Earth. For instance, the intricacies of the pulsar radio emission physics in their plasma-filled magnetospheres remain poorly understood despite more than 55 years of active research. That is partially because the pulsar radio emission exhibits rich and complex phenomena, especially at the single-pulse level. Additionally, previous instruments lacked the sensitivity and frequency coverage for the most detailed studies. Understanding the pulsar wideband emission physics is important in its own right and will also have implications for other likely related time-domain phenomena, such as fast radio bursts (FRBs) or the recently discovered long-period transients (LPTs). Hence, understanding the physics of pulsar magnetospheres is an important aspect of the Pulsars SKA key science theme, as detailed in the corresponding SKA Science Book chapter. In my talk, I will describe our efforts and the lessons learned from dealing with sub-GHz time-domain pulsar data from several SKA pathfinders at the Nançay Radio Observatory in France (NenuFAR, LOFAR) and the uGMRT in India. I will show how we constrain the pulsar emission characteristics in the frequency range ~20 to 800 MHz through telescope co-pointing, highlighting some recent results. Therefore, our work is extremely relevant to both the SKA-Low and SKA-Mid (Band 1) AA* telescopes. Based on our experience described above, I will then predict how the improved sensitivity and frequency coverage of the SKA AA* telescopes enable discoveries and advancement in our understanding of pulsar emission astrophysics. Along the same line, I will discuss our efforts in developing novel and improved data analysis tools inspired by recent advances in the field, which is essential as we enter the SKA era of abundant sensitivity and wide frequency coverage. The slides were presented at the SKAO General Science Meeting 2025 in Görlitz, Germany.