TESS Shines Light on the Origin of the Ambiguous Nuclear Transient ASASSN-18el
Autor: | Hinkle, Jason T., Kochanek, Christopher S., Shappee, Benjamin J., Vallely, Patrick J., Auchettl, Katie, Fausnaugh, Michael, Holoien, Thomas W. -S., Treiber, Helena P., Payne, Anna V., Gaudi, B. Scott, Prieto, Jose L., Stassun, Keivan G., Thompson, Todd A., Tonry, John L., Villanueva, Steven |
---|---|
Rok vydání: | 2022 |
Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
Space and Planetary Science Astrophysics::High Energy Astrophysical Phenomena FOS: Physical sciences Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics::Earth and Planetary Astrophysics Astrophysics - High Energy Astrophysical Phenomena |
DOI: | 10.48550/arxiv.2206.04071 |
Popis: | We analyze high-cadence data from the Transiting Exoplanet Survey Satellite (TESS) of the ambiguous nuclear transient (ANT) ASASSN-18el. The optical changing-look phenomenon in ASASSN-18el has been argued to be due to either a drastic change in the accretion rate of the existing active galactic nucleus (AGN) or the result of a tidal disruption event (TDE). Throughout the TESS observations, short-timescale stochastic variability is seen, consistent with an AGN. We are able to fit the TESS light curve with a damped-random-walk (DRW) model and recover a rest-frame variability amplitude of $\hat{\sigma} = 0.93 \pm 0.02$ mJy and a rest-frame timescale of $\tau_{DRW} = 20^{+15}_{-6}$ days. We find that the estimated $\tau_{DRW}$ for ASASSN-18el is broadly consistent with an apparent relationship between the DRW timescale and central supermassive black hole mass. The large-amplitude stochastic variability of ASASSN-18el, particularly during late stages of the flare, suggests that the origin of this ANT is likely due to extreme AGN activity rather than a TDE. Comment: 13 pages, 8 figures. Will be submitted to AAS journals. Comments welcome |
Databáze: | OpenAIRE |
Externí odkaz: |