The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array used to image black holes by combining millimetre/submillimetre radio observatories into an Earth-sized virtual telescope. I will review the latest findings of the EHT of AGN jets and horizon-scale studies, including new results on Sgr A* that are going to be published end of March. I will then give an...
Over the last decade, LOFAR has been used to measure radio signals from high-energy cosmic rays around 10^17 eV. These produce air showers, a cascade of secondary particles reaching a peak at an atmospheric depth called X_max which is sensitive to the primary particle's mass. The SKA-Low telescope being constructed in Australia presents a two orders of magnitude increase in number of antennas,...
We report on large-scale X-ray properties of the remarkable galaxy group Nest 200047 using 140 ks Chandra and 25 ks XMM-Newton data. The galaxy group Nest 200047 hosts a remarkably complex structure comprising four pairs of distinct radio lobes: the largest number of consecutive AGN outbursts known to date. Its outermost radio structures, extending to over 200 kpc radius, rival the largest...
The detection and characterisation of Tidal Disruption Events (TDEs) represents a unique powerful tool to investigate the mass distribution of Intermediate Mass Black Holes (IMBHs). These transients happen when a star approaches a Black Hole and is torn apart by tidal forces, releasing an amount of energy comparable to that of a SuperNova. Since current and future surveys are able to detect...
PSR J1906+0746 is a young binary pulsar with a spin period of P ∼ 144 ms in a very short 4-hr orbit around another neutron star. It provides a great opportunity to study both the relativistic spin-precession predicted by General Relativity (GR), and the little-understood radio pulsar emission in a single source in a self-consistent way. Discovered with Arecibo in 2004, it showed both a “main...
Historically, gamma-ray bursts (GRBs) are categorised into two classes: short GRBs (duration < 2 s) that are linked to compact object mergers and long GRBs linked to the death of massive stars. However, recent observations have shown that the population of GRBs is more complex. Understanding atypical GRBs can shed more light on this population and the progenitor systems. We present the...
The recent discovery of J191213.72-441045.1 (J1912-4410 hereafter) as the second white dwarf pulsar has firmly established white dwarf pulsars in compact binary systems as a separate class of objects, supporting formation models of white dwarf pulsars and offering new insights into the evolution of magnetic cataclysmic variables. The white dwarf in J1912-4410 has a spin period of 5.32 min and...
Fast radio bursts (FRBs) are millisecond-duration extragalactic radio transients of elusive origin that were first discovered in 2007. They are unique probes of the density and magnetization of the interstellar and intergalactic media and they will be even more useful when we better understand their sources, emission and environments. A small fraction of FRBs has been observed to repeat, which...
Mass transfer between stars is known to be of crucial importance in the evolution of multi-star systems, and is linked to the formation of a vast zoo of observed energetic transients. While mass transfer in binary stars has been studied intensively over the past decades, theoretical work on mass transfer in triples is still in its infancy. Understanding the disparities between mass transfer...
The core-collapse supernova remnant, Cassiopeia A (Cas A), is the youngest galactic remnant (~350 yrs) and is amongst the closest known (~ 3.4 kpc). Moreover, it has a secure supernova classification using light echo spectroscopy analysis. These make it an ideal source for studying supernova explosion mechanisms and progenitor systems. The recent James Webb Space Telescope (JWST) survey using...
