Period Evolution of Repeating Transients in Galactic Nuclei

Abstract

Wide-field survery have recently detected recurring optical and X-ray sources near galactic nuclei, with period spanning hours to years. These phenomena could result from repeated partial tidal disruptions of stars by supermassive black holes (SMBHs) or by interaction between star and SMBH-accretion discs. We study the physical processes that produce period changes in such sources, highlighting the key role of the interaction between the orbiting star and the accretion disc. We focus on ASASSN-14ko - a repeatedly flaring optical source with a mean period $P_0=115\mathrm{d}$ and a detected period decay $\dot{P}=-2.6\times 10^{-3}$ (Payne et al. 2022). We argue that the system's $\dot{P}$ is most compatible with true orbital decay produced by hydrodynamical drag as a star passes through the accretion disc on an inclined orbit, twice per orbit. The star is likely a sun-like star whose envelope is somewhat inflated, possibly due to tidal heating. Star-disc interaction inevitably leads to drag-induced stripping of mass from the star, which may be the dominant component in powering the observed flares. We discuss ASASSN-14ko's possible formation history and observational tests of our interpretation of the measured $\dot{P}$. Our results imply that partial tidal disruption events manifesting as repeating nuclear transients cannot be modeled without accounting for the cumulative impact of tidal heating over many orbits. We discuss the implications of our results for other repeating transients, and predict that the recurrence time of Quasi-Periodic Eruptions is expected to decay at a rate of order $|\dot{P}|\approx 10^{-6}-10^{-5}$.

arXiv comment13 pages, 4 figures. Accepted for publication in MNRAS

References in corpus (37)

• Elemental Abundances in QSOs: Star Formation and Galactic Nuclear Evolution at High Redshifts
• Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus
• X-ray Quasi-Periodic Eruptions from two previously quiescent galaxies
• X-ray quasi-periodic eruptions from the galactic nucleus of RX J1301.9+2747
• Self-intersection of the Fallback Stream in Tidal Disruption Events
• The metallicity of the most distant quasars
• Nonlinear Tides in Close Binary Systems
• ASASSN-14ko is a Periodic Nuclear Transient in ESO 253-G003
• Quasi-periodic eruptions from impacts between the secondary and a rigidly precessing accretion disc in an extreme mass-ratio inspiral system
• GSN 069 -- A Tidal Disruption Near-Miss
• Rates of Stellar Tidal Disruption
• X-ray Quasi-periodic Eruptions driven by Star-Disc Collisions : Application to GSN069 and Probing the Spin of Massive Black Holes
• Repeating tidal disruptions in GSN 069: Long-term evolution and constraints on quasi-periodic eruptions' models
• Pre-explosion spiral mass loss of a binary star merger
• Stellar transits across a magnetized accretion torus as a mechanism for plasmoid ejection
• Quasi-periodic eruptions from mildly eccentric unstable mass transfer in galactic nuclei
• Nonlinear Damping of Oscillations in Tidal-Capture Binaries
• Quasi--Periodic Eruptions from Galaxy Nuclei
• The Effect of Star--Disk Interactions on Highly Eccentric Stellar Orbits in Active Galactic Nuclei: A Disk Loss Cone and Implications for Stellar Tidal Disruption Events
• Deciphering the extreme X-ray variability of the nuclear transient eRASSt J045650.3-203750: A likely repeating partial tidal disruption event
• Quasi-periodic Eruptions from Helium Envelope of Hydrogen-deficient Stars Stripped by Supermassive Black Holes
• Unstable Mass Transfer from a Main-Sequence Star to a Supermassive Black Hole and Quasi-Periodic Eruptions
• Turbovelocity Stars: Kicks Resulting From the Tidal Disruption of Solitary Stars
• X-ray flares from Sgr A*: star-disk interactions?
• Alive and kicking: A new QPE phase in GSN 069 revealing a quiescent luminosity threshold for QPEs
• The interaction of core-collapse supernova ejecta with a companion star
• The rebrightening of a ROSAT-selected tidal disruption event: repeated weak partial disruption flares from a quiescent galaxy?
• Ejection and Capture Dynamics in Restricted Three-Body Encounters
• Stellar dynamics in a galactic centre surrounded by a massive accretion disc. I. Newtonian description
• Tidal disruptions of main sequence stars -- IV. Relativistic effects and dependence on black hole mass
• Capture of stars into gaseous discs around massive black holes: Alignment, circularization and growth
• Tidal disruption events from eccentric orbits and lessons learned from the noteworthy ASASSN-14ko
• An Amusing Look at the Host of the Periodic Nuclear Transient ASASSN-14ko Reveals a Second AGN
• Tidal capture of stars by supermassive black holes: implications for periodic nuclear transients and quasi-periodic eruptions
• Stellar capture by an accretion disc
• Angular Momentum Transfer in QPEs from Galaxy Nuclei
• Stellar/BH Population in AGN Disks: Direct Binary Formation from Capture Objects in Nuclei Clusters

Cited by in corpus (15)

• Probing orbits of stellar mass objects deep in galactic nuclei with quasi-periodic eruptions
• Rapid evolution of the recurrence time in the repeating partial tidal disruption event eRASSt J045650.3-203750
• Ticking away: the long-term X-ray timing and spectral evolution of eRO-QPE2
• QPEs from EMRI Debris Streams Impacting Accretion Disks in Galactic Nuclei
• Eppur si muove: Evidence of disc precession or a sub-milliparsec SMBH binary in the QPE-emitting galaxy GSN 069
• Fate of the remnant in tidal stripping event: repeating and non-repeating
• The orbital evolution of the tidally stripped star and disk-driven stable mass transfer for QPEs in GSN 069
• Dynamical Measurement of Supermassive Black Hole Masses: QPE Timing Method
• NICER observations reveal doubled timescales in Ansky's quasi-periodic eruptions (QPEs)
• Unveiling the Cosmic Dance of Repeated Nuclear Transient ASASSN-14ko: Insights from Multiwavelength Observations
• Testing the Shock-cooling Emission Model from Star-Disk Collisions for Quasiperiodic Eruptions
• Hubble constant measurement from QPEs as electromagnetic counterparts to extreme mass ratio inspirals
• MUSE IFU observations of galaxies hosting Tidal Disruption Events
• Irregular Repeating Tidal Disruption Events due to Diffusive Tides
• Repeating Nuclear Transients from Repeating Partial Tidal Disruption Events