| Title: |
Optically Overluminous Tidal Disruption Events: Outflow Properties and Implications for Extremely Relativistic Disruptions |
| Authors: |
Yao, Y; Alexander, KD; Lu, W; Somalwar, JJ; Ravi, V; Chornock, R; Margutti, R; Perley, DA; Miller-Jones, JCA; Beniamini, P; A.J, N; Bloom, JS; Christy, CT; Graham, MJ; Groom, SL; Hammerstein, E; Helou, G; Kasliwal, MM; Kulkarni, SR; Laher, RR; Mahabal, AA; Neveu, JRM; Riddle, R; Smith, R; van Velzen, S |
| Publisher Information: |
American Astronomical Society |
| Publication Year: |
2025 |
| Collection: |
Liverpool John Moores University: LJMU Research Online |
| Subject Terms: |
QB Astronomy; QC Physics |
| Description: |
Recent studies suggest that tidal disruption events (TDEs) with off-axis jets may manifest as optically overluminous events. To search for jet signatures at late times, we conducted radio observations of eight such optically overluminous (Mg,peak < −20.8 mag) TDEs with the Very Large Array. We detect radio counterparts in four events. The observed radio luminosities (L6 GHz ∼ 1038–1039 erg s−1) are two orders of magnitude lower than those of on-axis jetted TDEs, and we find no evidence for off-axis jets within a rest-frame time of 3 yr. Two of them (AT2022hvp and AT2021aeou) exhibit evolving radio emission, consistent with synchrotron emission from non-relativistic outflows launched near the time of first optical light. Two events (AT2020ysg and AT2020qhs) show no statistically significant variability, which can be attributed to either non-relativistic outflows or pre-existing active galactic nuclei. Compared to a control sample of fainter TDEs with Mg,peak > −20.5 mag observed at similar rest-frame timescales (trest ∼ 1.5 yr), our sample shows systematically more luminous radio emission, suggesting that optically overluminous TDEs may launch more powerful prompt non-relativistic outflows. We speculate that strong general relativistic effects near high-mass black holes (MBH ∼ 108 M⊙) may play a key role. These findings motivate further investigation into the nature of relativistic disruptions around massive black holes and the physical conditions necessary for jet formation. |
| Document Type: |
article in journal/newspaper |
| File Description: |
text |
| Language: |
English |
| ISSN: |
0004-637X |
| Relation: |
https://researchonline.ljmu.ac.uk/id/eprint/27567/1/Optically%20Overluminous%20Tidal%20Disruption%20Events%20Outflow%20Properties%20and%20Implications.pdf; Yao, Y, Alexander, KD, Lu, W, Somalwar, JJ, Ravi, V, Chornock, R, Margutti, R, Perley, DA ORCID logoorcid:0000-0001-8472-1996 , Miller-Jones, JCA, Beniamini, P, A.J, N, Bloom, JS, Christy, CT, Graham, MJ, Groom, SL, Hammerstein, E, Helou, G, Kasliwal, MM, Kulkarni, SR, Laher, RR, Mahabal, AA, Neveu, JRM, Riddle, R, Smith, R and van Velzen, S (2025) Optically Overluminous Tidal Disruption Events: Outflow Properties and Implications for Extremely Relativistic Disruptions. The Astrophysical Journal, 993 (198). pp. 1-13. ISSN 0004-637X |
| DOI: |
10.3847/1538-4357/ae08b3 |
| Availability: |
https://researchonline.ljmu.ac.uk/id/eprint/27567/; https://researchonline.ljmu.ac.uk/id/eprint/27567/1/Optically%20Overluminous%20Tidal%20Disruption%20Events%20Outflow%20Properties%20and%20Implications.pdf; https://doi.org/10.3847/1538-4357/ae08b3 |
| Rights: |
cc_by |
| Accession Number: |
edsbas.576D1B08 |
| Database: |
BASE |