Related papers: AT2020ohl: its nature and probable implications

We present ZTF20aajnksq (AT2020blt), a fast-fading ($\Delta r=2.4$ mag in $\Delta t=1.3$ days) red ($g-r\approx0.6$ mag) and luminous ($M_{1626}=-25.9$) optical transient at $z=2.9$ discovered by the Zwicky Transient Facility (ZTF).…

We present a pan-chromatic study of AT2017bcc, a nuclear transient that was discovered in 2017 within the skymap of a reported burst-like gravitational wave candidate, G274296. It was initially classified as a superluminous supernova, and…

The radio galaxy Fornax A (NGC 1316) is a prominent merger remnant in the outskirts of the Fornax cluster. Its giant radio lobes suggest the presence of a powerful AGN and thus a central supermassive black hole (SMBH). We present…

We present the discovery that ASASSN-14ko is a periodically flaring AGN at the center of the galaxy ESO 253-G003. At the time of its discovery by the All-Sky Automated Survey for Supernovae (ASAS-SN), it was classified as a supernova close…

AT2019wey is a new galactic X-ray binary that was first discovered as an optical transient by the Australia Telescope Large Area Survey (ATLAS) on December 7, 2019. AT2019wey consists of a black hole candidate as well as a low-mass…

We report the discovery of the first transient relativistic iron K{\alpha} line in an Active Galactic Nucleus (AGN) J1047+5907. The line was detected 21.5 days (rest-frame) after an X-ray coronal flare observed in 2008 and it exhibits…

AT2019pev is a nuclear transient in a narrow-line Seyfert 1 galaxy at $z=0.096$. The archival ultraviolet, optical and infrared data showed features of both tidal disruption events (TDEs) and active galactic nuclei (AGNs), and its nature is…

We present detailed spectroscopic analysis of the extraordinarily fast-evolving transient AT2018kzr. The transient's observed lightcurve showed a rapid decline rate, comparable to the kilonova AT2017gfo. We calculate a self-consistent…

Tidal disruption events (TDEs) that are spatially offset from the nuclei of their host galaxies offer a new probe of massive black hole (MBH) wanderers, binaries, triples, and recoiling MBHs. Here we present AT2024tvd, the first off-nuclear…

The many unusual properties of the enigmatic AT2018cow suggested that at least some subset of the empirical class of fast blue optical transients (FBOTs) represents a genuinely new astrophysical phenomenon. Unfortunately, the intrinsic…

We present multi-wavelength follow-up observations of the ATLAS discovered faint Iax supernova SN 2020kyg that peaked at an absolute magnitude of $M_g \approx -14.9 \pm 0.2$, making it another member of the faint Iax supernova population.…

Swift J1842.5$-$1124 is a transient Galactic black hole X-ray binary candidate, which underwent a new outburst in May 2020. We performed multi-epoch MeerKAT radio observations under the ThunderKAT Large Survey Programme, coordinated with…

Unusual stellar explosions represent an opportunity to learn about both stellar and galaxy evolution. Mapping the atomic gas in host galaxies of such transients can lead to an understanding of the conditions triggering them. We provide…

We present results from a search for a radio transient associated with the LIGO/Virgo source S190814bv, a likely neutron star-black hole (NSBH) merger, with the Australian Square Kilometre Array Pathfinder. We imaged a $30\,{\rm deg}^2$…

Infrared echo has proven to be an effective means to discover transient accretion events of supermassive black holes (SMBHs), such as tidal disruption events (TDEs) and changing-look active galactic nuclei (AGNs), in dusty circumnuclear…

The search and study of close pairs of supermassive black holes (SMBHs) is important in the study of galaxy mergers which can possibly trigger active galactic nucleus (AGN) activity, and in the context of their evolution into the…

Our current understanding of radio-loud AGN comes predominantly from studies at frequencies of 5 GHz and below. With the recent completion of the Australia Telescope 20 GHz (AT20G) survey, we can now gain insight into the high-frequency…

Wide-field survery have recently detected recurring optical and X-ray sources near galactic nuclei, with period spanning hours to years. These phenomena could result from repeated partial tidal disruptions of stars by supermassive black…

PSO J334.2028+1.4075 (PSO J334) is a luminous quasar located at redshift z=2.06. The source gained attention when periodic flux density variations were discovered in its optical light curve. These variations were initially interpreted as…

The nuclear transient AT2019cuk/Tick Tock/SDSS J1430+2303 has been suggested to harbor a supermassive black hole (SMBH) binary near coalescence. We report results from high-cadence NICER X-ray monitoring with multiple visits per day from…