Catching jetted tidal disruption events early in millimetre

Abstract

Relativistic jets can form from at least some tidal disruption events (TDEs) of (sub-)stellar objects around supermassive black holes. We detect the millimeter (MM) emission of IGR J12580+0134 -the nearest TDE known in the galaxy NGC 4845 at the distance of only 17 Mpc, based on Planck all-sky survey data. The data show significant flux jumps after the event, followed by substantial declines, in all six high frequency Planck bands from 100 GHz to 857 GHz. We further show that the evolution of the MM flux densities are well consistent with our model prediction from an off-axis jet, as was initially suggested from radio and X-ray observations. This detection represents the second TDE with MM detections; the other is Sw J1644+57, an on-axis jetted TDE at redshift of 0.35. Using the on-and off-axis jet models developed for these two TDEs as templates, we estimate the detection potential of similar events with the Large Millimeter Telescope (LMT) and the Atacama Large Millimeter/submillimeter Array (ALMA). Assuming an exposure of one hour, we find that the LMT (ALMA) can detect jetted TDEs up to redshifts z ∼ 1 (2), for a typical disrupted star mass of ∼ 1 M ⊙ . The detection rates of on-and off-axis TDEs can be as high as ∼ 0.6 (13) and 10 (220) per year, respectively, for the LMT (ALMA). We briefly discuss how such observations, together with follow-up radio monitoring, may lead to major advances in understanding the jetted TDEs themselves and the ambient environment of the CNM.

The Curious Case of ASASSN-20hx: A Slowly Evolving, UV- and X-Ray-Luminous, Ambiguous Nuclear Transient

“…While this estimate requires several assumptions about the type of transient and radio evolution, it is sufficient to show that ASASSN-20hx is considerably fainter than the jetted/relativistic TDEs Swift J2058+05 and Swift J1644+57. This likely suggests that either ASASSN-20hx did not launch a strong jet or the jet was off-axis (Irwin et al 2015;Yuan et al 2016).…”

The Curious Case of ASASSN-20hx: A Slowly-Evolving, UV and X-ray Luminous, Ambiguous Nuclear Transient

“…While this estimate requires several assumptions about the type of transient and radio evolution, it is sufficient to show that ASASSN-20hx is considerably fainter than the jetted/relativistic TDEs Swift J2058+05 and Swift J1644+57. This likely suggests that ASASSN-20hx either did not launch a strong jet or that the jet was off-axis (Irwin et al 2015;Yuan et al 2016).…”

CCAT-Prime: science with an ultra-widefield submillimeter observatory on Cerro Chajnantor

“…Finally, CCAT-prime may also be sensitive enough to detect rare extragalactic transient events provided the observing strategy and source extraction software are carefully optimized. Detection expectations for tidal disruption of sub-stellar objects around supermassive black holes have been calculated for the LMT and ALMA [90] and need to be refined for CCAT-prime. Millimeter-wave discoveries of outbursts from AGN (e.g.…”