Seeing Double: The Theory Defying Twin Flares of TDE 2022dbl
Abstract
Partial tidal disruption events, in which a star survives a close passage by a supermassive black hole and may be disrupted again on a subsequent encounter, provide a unique probe of supermassive black hole properties and accretion physics. We examine TDE 2022dbl, a partial tidal disruption event candidate that exhibits two separate UV/optical flares, using 11 new optical spectra, updated UV/optical photometry, and a Keck-II/ESI host-galaxy spectrum. We trace the evolution of the prominent blended N III + He II feature across both flares and find that the blend evolves from N III-dominated to He II-dominated emission, which may reflect changing ionization conditions and a declining efficiency of Bowen fluorescence. The two flares show similar thermal evolution and spectral features, supporting a partial-disruption scenario. The second flare exhibits a broader, plateau-like peak, a longer decline timescale, and less extreme line velocities than the first flare. We suggest that these differences arise from the interaction between debris from the second disruption and an accretion disk formed during the first flare. From the host-galaxy velocity dispersion, we infer a black hole mass of log10(MBH/M⊙)=6.01±0.45. No third flare has been detected at the expected recurrence epoch, leading us to propose a new interpretation in which a positive-energy kick during ballistic core reformation delays the return of the surviving remnant.
Related
- Fast Radio Bursts from Monster Shocks and Flares of Inspiraling Binary Neutron Stars: A Kinetic Model for Double Pulsar
- Recurrent double-peaked γ-ray sub-flares in PKS 1424-418
- Seeing in the Dark: Gravitational Waves from Resonant Production of Dark Photon Dark Matter
- Is DESI Seeing Dynamical Dark Energy, or a Cosmic Glitch in Gravity?
- Probabilistic Machine Learning for Short-Term Atmospheric Seeing Forecasting
BibTeX
@misc{guo2026seeing,
title = {{Seeing Double: The Theory Defying Twin Flares of TDE 2022dbl}},
author = {Xinze Guo and Ryan Chornock and Raffaella Margutti and Yuhan Yao and Erica Hammerstein and Natalie LeBaron and S. Bradley Cenko and Matthew J. Graham and Dina Ibrahimzade and Itai Sfaradi and Jean Somalwar and Robert Stein and Eli Wiston and Joahan Castaneda Jaimes and Mansi M. Kasliwal and Russ R. Laher},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.18840},
eprint = {2610.18840},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.18840},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Seeing Double: The Theory Defying Twin Flares of TDE 2022dbl
AU - Xinze Guo
AU - Ryan Chornock
AU - Raffaella Margutti
AU - Yuhan Yao
AU - Erica Hammerstein
AU - Natalie LeBaron
AU - S. Bradley Cenko
AU - Matthew J. Graham
AU - Dina Ibrahimzade
AU - Itai Sfaradi
AU - Jean Somalwar
AU - Robert Stein
AU - Eli Wiston
AU - Joahan Castaneda Jaimes
AU - Mansi M. Kasliwal
AU - Russ R. Laher
PY - 2026
DA - 2026/10/13
PB - arXiv
DO - 10.48550/arxiv.2610.18840
UR - https://arxiv.org/abs/2610.18840
AB - Partial tidal disruption events, in which a star survives a close passage by a supermassive black hole and may be disrupted again on a subsequent encounter, provide a unique probe of supermassive black hole properties and accretion physics. We examine TDE 2022dbl, a partial tidal disruption event candidate that exhibits two separate UV/optical flares, using 11 new optical spectra, updated UV/optical photometry, and a Keck-II/ESI host-galaxy spectrum. We trace the evolution of the prominent blended N III + He II feature across both flares and find that the blend evolves from N III-dominated to He II-dominated emission, which may reflect changing ionization conditions and a declining efficiency of Bowen fluorescence. The two flares show similar thermal evolution and spectral features, supporting a partial-disruption scenario. The second flare exhibits a broader, plateau-like peak, a longer decline timescale, and less extreme line velocities than the first flare. We suggest that these differences arise from the interaction between debris from the second disruption and an accretion disk formed during the first flare. From the host-galaxy velocity dispersion, we infer a black hole mass of log_10(M_BH/M_⊙)=6.01±0.45. No third flare has been detected at the expected recurrence epoch, leading us to propose a new interpretation in which a positive-energy kick during ballistic core reformation delays the return of the surviving remnant.
ER -