Unveiling the mysteries of long period radio transients.

Objective

Long-period transients (LPTs) are a newly discovered class of sporadically active radio sources with minute-to-hour periodicities. Their luminosities exceed what can be powered by rotational spin-down alone, pointing to alternative energy reservoirs. Only 12 LPTs are known: some confirmed as white dwarf–M dwarf binaries, while others may be magnetars or magnetized white dwarfs. Theory suggests LPTs trace hidden stages of compact object evolution—for example, progenitors of cataclysmic variables or old magnetars reactivated by magnetic field changes. They thus open a new window on compact binary pathways and coherent emission physics. This project asks: Do LPTs represent unseen evolutionary stages of white dwarfs or neutron stars, and what powers their emission? I will pursue three goals: 1) Expand detections by exploiting LOFAR’s 8-second imaging to search 3000 LoTSS fields with my optimized pipeline, incorporating dispersion correction to recover faint bursts, and developing a real-time image-based transient detection system for LOFAR2.0. 2) Classify populations through multi-wavelength follow-up: X-rays to test magnetar origins and optical data to reveal companions or WD progenitors, distinguishing isolated versus interacting systems. 3) Probe emission physics via high-time-resolution polarimetric radio follow-up, measuring spin, polarization, and burst microstructure to constrain energetics, local environments, and emission mechanisms. This Action will deliver the first systematic framework for studying LPTs, expanding the sample to a statistically meaningful population, placing them in an evolutionary context, and constraining their energy budgets. I will also release a public catalog of LPTs and reproducible analysis tools for the community. Performed at UvA, this project will provide the training needed for my development into an independent research group leader, while positioning LPTs as a key class of compact objects in the era of LOFAR2.0 and the SKA.