Long fading mid-infrared emission in transient coronal line emitters: dust echo of a tidal disruption flare
- CAS Key Laboratory for Researches in Galaxies and Cosmology, University of Sciences and Technology of China, Hefei, Anhui 230026 (China)
- Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
The sporadic accretion following the tidal disruption of a star by a super-massive black hole (TDE) leads to a bright UV and soft X-ray flare in the galactic nucleus. The gas and dust surrounding the black hole responses to such a flare with an echo in emission lines and infrared emission. In this paper, we report the detection of long fading mid-IR emission lasting up to 14 years after the flare in four TDE candidates with transient coronal lines using the WISE public data release. We estimate that the reprocessed mid-IR luminosities are in the range between 4×10{sup 42} and 2×10{sup 43} erg s{sup −1} and dust temperature in the range of 570–800 K when WISE first detected these sources three to five years after the flare. Both luminosity and dust temperature decrease with time. We interpret the mid-IR emission as the infrared echo of the tidal disruption flare. We estimate the UV luminosity at the peak flare to be 1 to 30 times 10{sup 44} erg s{sup −1} and that for warm dust masses to be in the range of 0.05–1.3 M{sub ⊙} within a few parsecs. Our results suggest that the mid-infrared echo is a general signature of TDE in the gas-rich environment.
- OSTI ID:
- 22868408
- Journal Information:
- Astrophysical Journal, Vol. 832, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE WISE DETECTION OF AN INFRARED ECHO IN TIDAL DISRUPTION EVENT ASASSN-14li
Discovery of transient infrared emission from dust heated by stellar tidal disruption flares