This talk was part of the UH Centre for Astrophysics Research (CAR) 2023-2024 seminar series. For the ongoing programme, please see: https://www.herts.ac.uk/research/cent...

Date: 4 Oct 2023
Speaker: Dr Philip Wiseman – University of Southampton
Title: AT2021lwx and the Super ANTs: Seeking the power source of the Universe’s most energetic eruptions

Abstract: Ambiguous nuclear transients (ANTs) are extremely luminous flares occurring in the centres of galaxies. The most energetic of all, AT2021lwx, at redshift 1, shows a single optical brightening to a luminosity close to 10^46 erg/s, followed by a smooth decline over more than a year in the rest frame.The luminosity and timescale indicate that a large supermassive black hole is likely the central engine, but how the energy is released, and from what, remains a mystery. In this talk I will summarise the observed and inferred properties of AT2021lwx and the candidate scenarios. I will present a preliminary compilation of “super-ANTs” from the Zwicky Transient Facility and Dark Energy Survey, and look forward to the exciting prospect and observational challenge of constructing large ANT samples in upcoming transient surveys.