arXiv subjects

Sjoert van Velzen

Publications and source records attributed to Sjoert van Velzen.

At least 37 records · Page 2Linked to original sources

arXiv2025

Disentangling transients and their host galaxies with Scarlet2: A framework to forward model multi-epoch imaging

Many science cases for wide-field time-domain surveys rely on accurate identification and characterization of the galaxies hosting transient and variable objects. In the era of the Legacy Survey of Space and Time (LSST) at the Vera C. Rubin Observatory the number of known transient and variable sources will grow by orders of magnitude, and many of these sources will be blended with their host galaxies and neighboring galaxies. A diverse range of applications - including the classification of nuclear and non-nuclear sources, identification of potential host galaxies, extraction of host galaxy SEDs without requiring a transient-free reference image, and combined analysis of photometry from multiple surveys - will benefit from a flexible framework to model time-domain imaging of transients. We describe a time-domain extension of the Scarlet2 scene modeling code for multi-epoch, multi-band, and multi-resolution imaging data to extract simultaneous transient and host galaxy models. Scarlet2 leverages the benefits of data-driven priors on galaxy morphology, is fully GPU compatible, and can jointly model multi-resolution data from ground and space-based surveys. We demonstrate the method on simulated LSST-like supernova imaging, low-resolution Zwicky Transient Facility imaging of tidal disruption events, and Hyper Suprime Cam imaging of variable AGN out to z = 4 in the COSMOS fields. We show that Scarlet2 models provide accurate transient and host galaxy models as well as accurate measurement of host-transient spatial offsets, and demonstrate future applications to the search for 'wandering' massive black holes.

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arXiv2025

AGN flares as counterparts to LIGO/Virgo mergers: No confident causal connection in spatial correlation analysis

The primary formation channel for the stellar-mass Binary Black Holes which have been detected merging by the LIGO-Virgo- KAGRA (LVK) collaboration is yet to be discerned. One of the main reason is that the detection of an Electromagnetic counterpart to such Gravitational Wave (GW) events, which could signpost their formation site, has so far been elusive. Recently, 20 Active Galactic Nuclei flaring activities detected by the Zwicky Transient Facility have been investigated as potential counterparts of GW events by Graham et al. (2023). We present the results of a spatial correlation analysis that involves such events and uses the up-to-date posterior samples of 78 mergers, detected during the third observing run of the LVK collaboration. We apply a likelihood method which takes into account the exact position of the flares within the 3D sky map of the GW events. We place an upper limit of 0.155 at a 90 per cent credibility level on the fraction of the detected coalescences that are physically related to an observed flare, whose posterior probability distribution peaks at a null value. Finally, we show that the typically larger values of the masses of the GW-events, which host at least one flare in their localisation volume, are also consistent with the no-connection hypothesis. This is because of a positive correlation between binary masses and the size of the localisation uncertainties.

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arXiv2024

Counting the Unseen II: Tidal Disruption Event Rates in Nearby Galaxies with REPTiDE

Tidal disruption events (TDEs) are a class of transients that occur when a star is destroyed by the tides of a massive black hole (MBH). Their rates encode valuable MBH demographic information, but this can only be extracted if accurate TDE rate predictions are available for comparisons with observed rates. In this work, we present a new, observer-friendly Python package called REPTiDE, which implements a standard loss cone model for computing TDE rates given a stellar density distribution and an MBH mass. We apply this software to a representative sample of 91 nearby galaxies over a wide range of stellar masses with high-resolution nuclear density measurements from arXiv:2407.10911. We measure per-galaxy TDE rates ranging between 10$^{-7.7}$ and 10$^{-2.9}$ per year and find that the sample-averaged rates agree well with observations. We find a turnover in the TDE rate as a function of both galaxy stellar mass and black hole mass, with the peak rates being observed in galaxies at a galaxy mass of $10^{9.5}$ M$_\odot$ and a black hole mass of $10^{6.5}$ M$_\odot$. Despite the lower TDE rates inferred for intermediate-mass black holes, we find that they have gained a higher fraction of their mass through TDEs when compared to higher mass black holes. This growth of lower mass black holes through TDEs can enable us to place interesting constraints on their spins; we find maximum spins of $a_\bullet \approx 0.9$ for black holes with masses below $\sim10^{5.5}$ M$_\odot$.

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arXiv2024

Constraining the AGN formation channel for detected black hole binary mergers up to z=1.5 with the Quaia catalogue

Statistical analyses based on the spatial correlation between the sky maps of Gravitational Wave (GW) events and the positions of potential host environments are a powerful tool to infer the origin of the black hole binary mergers that have been detected by the LIGO, Virgo, and KAGRA instruments. In this paper, we tighten our previous constraints on the fraction of detected GW events that may have originated from Active Galactic Nuclei (AGN). We consider 159 mergers detected not later than June 1st, 2024, and the all-sky quasar catalogue Quaia. We increase by a factor of 5.3 and 114 the number of considered GW sources and AGN respectively, also extending our analysis from redshift $0.3$ to $1.5$. This is possible thanks to the uniformity of the AGN catalogue and its high level of completeness, which we estimate as a function of redshift and luminosity. We find at a 95 per cent credibility level that un-obscured AGN with a bolometric luminosity higher than $10^{44.5}{\rm erg\ s}^{-1}$ ($10^{45}{\rm erg\ s}^{-1}$) do not contribute to more than the 21 (11) per cent of the detected GW events.

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arXiv2024

The optical, UV-plateau and X-ray tidal disruption event luminosity functions reproduced from first principles

We reproduce the luminosity functions of the early-time peak optical luminosity, the late-time UV plateau luminosity, and the peak X-ray luminosity of tidal disruption events, using an entirely first-principles theoretical approach. We do this by first fitting three free parameters of the tidal disruption event black hole mass distribution using the observed distribution of late time UV plateau luminosities, using a time-dependent relativistic accretion model. Using this black hole mass distribution we are then, with no further free parameters of the theory, able to reproduce exactly the peak X-ray luminosity distribution of the tidal disruption event population. This proves that the X-ray luminosity of tidal disruption events are sourced from the same accretion flows which produce the late time UV plateau. Using an empirical scaling relationship between peak optical luminosities and black hole masses, itself calibrated using the same relativistic accretion theory, we are able to reproduce the observed peak optical luminosity function, again with no additional free parameters. Implications of these results include that there is no tidal disruption event "missing energy problem", that the optical and X-ray selected tidal disruption event populations are drawn from the same black hole mass distribution, that the early time optical luminosity in tidal disruption events is somewhat simple, at least on the population level, and that future LSST observations will be able to constrain the black hole mass function at low masses.

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arXiv2024

Counting the Unseen I: Nuclear Density Scaling Relations for Nucleated Galaxies

The volumetric rate of tidal disruption events (TDEs) encodes information on the still-unknown demographics of central massive black holes (MBHs) in low-mass galaxies ($\lesssim 10^9$~M$_\odot$). Theoretical TDE rates from model galaxy samples can extract this information, but this requires accurately defining the nuclear stellar density structures. This region is typically dominated by nuclear star clusters (NSCs), which have been shown to increase TDE rates by orders of magnitude. Thus, we assemble the largest available sample of pc-scale 3-D density profiles that include NSC components. We deproject the PSF-deconvolved surface brightness profiles of 91 nearby galaxies of varying morphology and combine these with nuclear mass-to-light ratios estimated from measured colors or spectral synthesis to create 3-D mass density profiles. We fit the inner 3-D density profile to find the best-fit power-law density profile in each galaxy. We compile this information as a function of galaxy stellar mass to fit new empirical density scaling relations. These fits reveal positive correlations between galaxy stellar mass and central stellar density in both early- and late-type galaxies. We find that early-type galaxies have somewhat higher densities and shallower profiles relative to late-type galaxies at the same mass. We also use the density profiles to estimate the influence radius of each galaxy's MBH and find that the sphere of influence was likely resolved in most cases. These new relations will be used in future works to build mock galaxy samples for dynamical TDE rate calculations, with the aim of constraining MBH demographics in low-mass galaxies.

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arXiv2024

Flaires: A Comprehensive Catalog of Dust-Echo-like Infrared Flares

Context: Observations of transient emission from extreme accretion events onto supermassive black holes can reveal conditions in the center of galaxies and the black hole itself. Most recently, they have been suggested to be emitters of high-energy neutrinos. If it is suddenly rejuvenated accretion or a tidal disruption event (TDE) is not clear in most cases. Aims: We expanded on existing samples of infrared flares to compile the largest and most complete list available. A large sample size is necessary to provide high enough statistics for far away and faint objects to estimate their rate. Our catalog is large enough to facilitate a preliminary study of the rate evolution with redshift for the first time. Methods: We compiled a sample of 40 million galaxies, and, using a custom, publicly available pipeline, analyzed the WISE light curves for these 40 million objects using the Bayesian Blocks algorithm. We selected promising candidates for dust echos of transient accretion events and inferred the luminosity, extension, and temperature of the hot dust by fitting a blackbody spectrum. Results: We established a clean sample of 823 dust-echo-like infrared flares, of which we can estimate the dust properties for 568. After removing 70 objects with possible contribution by synchrotron emission, the luminosity, extension, and temperature are consistent with dust echos. Estimating the dust extension from the light curve shape revealed that the duration of the incident flare is broadly compatible with the duration of TDEs. The resulting rate per galaxy is consistent with the latest measurements of infrared-detected TDEs and appears to decline at increasing redshift. Conclusions: Although systematic uncertainties may impact the calculation of the rate evolution, this catalog will enable further research in phenomena related to dust-echos from TDEs and extreme accretion flares.

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arXiv2024

The Peculiar Radio Evolution of the Tidal Disruption Event ASASSN-19bt

We present detailed radio observations of the tidal disruption event (TDE) ASASSN-19bt/AT2019ahk, obtained with the Australia Telescope Compact Array (ATCA), the Atacama Large Millimeter/submillimeter Array (ALMA), and the MeerKAT radio telescopes, spanning 40 to 1464 days after the onset of the optical flare. We find that ASASSN-19bt displays unusual radio evolution compared to other TDEs, as the peak brightness of its radio emission increases rapidly until 457 days post-optical discovery and then plateaus. Using a generalized approach to standard equipartition techniques, we estimate the energy and corresponding physical parameters for two possible emission geometries: a non-relativistic spherical outflow and a relativistic outflow observed from an arbitrary viewing angle. We find that the non-relativistic solution implies a continuous energy rise in the outflow from $E\sim10^{46}$ erg to $E\sim10^{49}$ erg with $β\approx 0.05$, while the off-axis relativistic jet solution instead suggests $E\approx10^{52}$ erg with $Γ\sim10$ erg at late times in the maximally off-axis case. We find that neither model provides a holistic explanation for the origin and evolution of the radio emission, emphasizing the need for more complex models. ASASSN-19bt joins the population of TDEs that display unusual radio emission at late times. Conducting long-term radio observations of these TDEs, especially during the later phases, will be crucial for understanding how these types of radio emission in TDEs are produced.

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arXiv2024

A systematic analysis of the X-ray emission in optically selected tidal disruption events: observational evidence for the unification of the optically and X-ray selected populations

We present a systematic analysis of the X-ray emission of a sample of 17 optically selected, X-ray-detected tidal disruption events (TDEs) discovered between 2014 and 2021. The X-ray light curves show a diverse range of temporal behaviors, with most sources not following the expected power-law decline. The X-ray spectra are mostly extremely soft and consistent with thermal emission from the innermost region of an accretion disk, which cools as the accretion rate decreases. Three sources show formation of a hard X-ray corona, at late-times. The spectral energy distribution shape, probed by the ratio ($L_{\rm\,BB}/L_{\rm\,X}$) between the UV/optical and X-ray, shows a wide range $L_{\rm BB}/L_{\rm X}\,\in\,(0.5,\,3000)$ at early-times, and converges to disk-like values $L_{\rm\,BB}/L_{\rm\,X}\,\in\,(0.5,\,10)$ at late-times. We estimate the fraction of optically discovered TDEs with $L_{\rm\,X}\,\geq 10^{42}~\rm{erg}~\rm{s}^{-1} $ to be at least $40\%$, and show that X-ray loudness is independent of black hole mass. We argue that distinct disk formation time scales are unlikely to fully explain the diverse range of X-ray evolutions. We combine our sample with X-ray discovered ones to construct an X-ray luminosity function, best fitted by a broken power-law, with a break at $L_{\rm\,X} \approx 10^{44}~\rm{erg}~\rm{s}^{-1} $. We show that there is no dichotomy between optically and X-ray selected TDEs, instead there is a continuum of early time $L_{\rm\,BB}/L_{\rm\,X}$, at least as wide as $L_{\rm\,BB}/L_{\rm\,X}\,\in\,(0.1,\,3000)$, with optical/X-ray surveys selecting preferentially, but not exclusively, from the higher/lower end of the distribution. Our findings are consistent with unification models for the overall TDE population.

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arXiv2024

Neutrino follow-up with the Zwicky Transient Facility: Results from the first 24 campaigns

The Zwicky Transient Facility (ZTF) performs a systematic neutrino follow-up program, searching for optical counterparts to high-energy neutrinos with dedicated Target-of-Opportunity (ToO) observations. Since first light in March 2018, ZTF has taken prompt observations for 24 high-quality neutrino alerts from the IceCube Neutrino Observatory, with a median latency of 12.2 hours from initial neutrino detection. From two of these campaigns, we have already reported tidal disruption event (TDE) AT 2019dsg and likely TDE AT 2019fdr as probable counterparts, suggesting that TDEs contribute >7.8% of the astrophysical neutrino flux. We here present the full results of our program through to December 2021. No additional candidate neutrino sources were identified by our program, allowing us to place the first constraints on the underlying optical luminosity function of astrophysical neutrino sources. Transients with optical absolutes magnitudes brighter that $-21$ can contribute no more than 87% of the total, while transients brighter than $-22$ can contribute no more than 58% of the total, neglecting the effect of extinction and assuming they follow the star formation rate. These are the first observational constraints on the neutrino emission of bright populations such as superluminous supernovae. None of the neutrinos were coincident with bright optical AGN flares comparable to that observed for TXS 0506+056/IC170922A, with such optical blazar flares producing no more than 26% of the total neutrino flux. We highlight the outlook for electromagnetic neutrino follow-up programs, including the expected potential for the Rubin Observatory.

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arXiv2024

$\texttt{tdescore}$: An Accurate Photometric Classifier for Tidal Disruption Events

Optical surveys have become increasingly adept at identifying candidate Tidal Disruption Events (TDEs) in large numbers, but classifying these generally requires extensive spectroscopic resources. Here we present $\texttt{tdescore}$, a simple binary photometric classifier that is trained using a systematic census of $\sim$3000 nuclear transients from the Zwicky Transient Facility (ZTF). The sample is highly imbalanced, with TDEs representing $\sim$2% of the total. $\texttt{tdescore}$ is nonetheless able to reject non-TDEs with 99.6% accuracy, yielding a sample of probable TDEs with recall of 77.5% for a precision of 80.2%. $\texttt{tdescore}$ is thus substantially better than any available TDE photometric classifier scheme in the literature, with performance not far from spectroscopy as a method for classifying ZTF nuclear transients, despite relying solely on ZTF data and multi-wavelength catalogue cross-matching. In a novel extension, we use `SHapley Additive exPlanations' ($\texttt{SHAP}$) to provide a human-readable justification for each individual $\texttt{tdescore}$ classification, enabling users to understand and form opinions about the underlying classifier reasoning. $\texttt{tdescore}$ can serve as a model for photometric identification of TDEs with time-domain surveys, such as the upcoming Rubin observatory.

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arXiv2024

Establishing accretion flares from massive black holes as a source of high-energy neutrinos

The origin of cosmic high-energy neutrinos remains largely unexplained. For high-energy neutrino alerts from IceCube, a coincidence with time-variable emission has been seen for three different types of accreting black holes: (1) a gamma-ray flare from a blazar (TXS 0506+056), (2) an optical transient following a stellar tidal disruption event (TDE; AT2019dsg), and (3) an optical outburst from an active galactic nucleus (AGN; AT2019fdr). For the latter two sources, infrared follow-up observations revealed a powerful reverberation signal due to dust heated by the flare. This discovery motivates a systematic study of neutrino emission from all supermassive black hole with similar dust echoes. Because dust reprocessing is agnostic to the origin of the outburst, our work unifies TDEs and high-amplitude flares from AGN into a population that we dub accretion flares. Besides the two known events, we uncover a third flare that is coincident with a PeV-scale neutrino (AT2019aalc). Based solely on the optical and infrared properties, we estimate a significance of 3.6$σ$ for this association of high-energy neutrinos with three accretion flares. Our results imply that at least ~10% of the IceCube high-energy neutrino alerts could be due to accretion flares. This is surprising because the sum of the fluence of these flares is at least three orders of magnitude lower compared to the total fluence of normal AGN. It thus appears that the efficiency of high-energy neutrino production in accretion flares is increased compared to non-flaring AGN. We speculate that this can be explained by the high Eddington ratio of the flares.

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arXiv2024

A Case for a Binary Black Hole System Revealed via Quasi-Periodic Outflows

Binaries containing a compact object orbiting a supermassive black hole are thought to be precursors of gravitational wave events, but their identification has been extremely challenging. Here, we report quasi-periodic variability in X-ray absorption which we interpret as quasi-periodic outflows (QPOuts) from a previously low-luminosity active galactic nucleus after an outburst, likely caused by a stellar tidal disruption. We rule out several models based on observed properties and instead show using general relativistic magnetohydrodynamic simulations that QPOuts, separated by roughly 8.3 days, can be explained with an intermediate-mass black hole secondary on a mildly eccentric orbit at a mean distance of about 100 gravitational radii from the primary. Our work suggests that QPOuts could be a new way to identify intermediate/extreme-mass ratio binary candidates.

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arXiv2024

X-ray eruptions every 22 days from the nucleus of a nearby galaxy

Galactic nuclei showing recurrent phases of activity and quiescence have recently been discovered, with recurrence times as short as a few hours to a day -- known as quasi-periodic X-ray eruption (QPE) sources -- to as long as hundreds to a thousand days for repeating nuclear transients (RNTs). Here we present a multi-wavelength overview of Swift J023017.0+283603 (hereafter Swift J0230+28), a source that exhibits repeating and quasi-periodic X-ray flares from the nucleus of a previously unremarkable galaxy at $\sim$ 165 Mpc, with a recurrence time of approximately 22 days, an intermediary timescale between known RNTs and QPE sources. The source also shows transient radio emission, likely associated with the X-ray emission. Such recurrent soft X-ray eruptions, with no accompanying UV/optical emission, are strikingly similar to QPE sources. However, in addition to having a recurrence time that is $\sim 25$ times longer than the longest-known QPE source, Swift J0230+28's eruptions exhibit somewhat distinct shapes and temperature evolution than the known QPE sources. Scenarios involving extreme mass ratio inspirals are favored over disk instability models. The source reveals an unexplored timescale for repeating extragalactic transients and highlights the need for a wide-field, time-domain X-ray mission to explore the parameter space of recurring X-ray transients.

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arXiv2024

Panic at the ISCO: time-varying double-peaked broad lines from evolving accretion disks are common amongst optically variable AGN

About 3-10\% of Type I active galactic nuclei (AGN) have double-peaked broad Balmer lines in their optical spectra originating from the motion of gas in their accretion disk. Double-peaked profiles arise not only in AGN, but occasionally appear during optical flares from tidal disruption events and changing-state AGN. In this paper we identify 250 double-peaked emitters (DPEs) amongst a parent sample of optically variable broad-line AGN in the Zwicky Transient Facility (ZTF) survey, corresponding to a DPE fraction of 19\%. We model spectra of the broad H$α$ emission line regions and provide a catalog of the fitted accretion disk properties for the 250 DPEs. Analysis of power spectra derived from the 5 year ZTF light curves finds that DPE light curves have similar amplitudes and power law indices to other broad-line AGN. Follow-up spectroscopy of 12 DPEs reveals that $\sim$50\% display significant changes in the relative strengths of their red and blue peaks over long $10-20$ year timescales, indicating that broad-line profile changes arising from spiral arm or hotspot rotation are common amongst optically variable DPEs. Analysis of the accretion disk parameters derived from spectroscopic modeling provides evidence that DPEs are not in a special accretion state, but are simply normal broad-line AGN viewed under the right conditions for the accretion disk to be easily visible. We include inspiraling SMBH binary candidate SDSSJ1430+2303 in our analysis, and discuss how its photometric and spectroscopic variability is consistent with the disk-emitting AGN population in ZTF.

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arXiv2024

A New Population of Mid-Infrared-Selected Tidal Disruption Events: Implications for Tidal Disruption Event Rates and Host Galaxy Properties

Most tidal disruption events (TDEs) are currently found in time-domain optical and soft X-ray surveys, both of which are prone to significant obscuration. The infrared (IR), however, is a powerful probe of dust-enshrouded environments, and hence, we recently performed a systematic search of NEOWISE mid-IR data for nearby, obscured TDEs within roughly 200 Mpc. We identified 18 TDE candidates in galactic nuclei, using difference imaging to uncover nuclear variability amongst significant host galaxy emission. These candidates were selected based on the following IR light curve properties: (1) $L_\mathrm{W2}\gtrsim10^{42}$ erg s$^{-1}$ at peak, (2) fast rise, followed by a slow, monotonic decline, (3) no significant prior variability, and (4) no evidence for AGN activity in WISE colors. The majority of these sources showed no variable optical counterpart, suggesting that optical surveys indeed miss numerous obscured TDEs. Using narrow line ionization levels and variability arguments, we identified 6 sources as possible underlying AGN, yielding a total of 12 TDEs in our gold sample. This gold sample yields a lower limit on the IR-selected TDE rate of $2.0\pm0.3\times10^{-5}$ galaxy$^{-1}$ year$^{-1}$ ($1.3\pm0.2\times10^{-7}$ Mpc$^{-3}$ year$^{-1}$), which is comparable to optical and X-ray TDE rates. The IR-selected TDE host galaxies do not show a green valley overdensity nor a preference for quiescent, Balmer strong galaxies, which are both overrepresented in optical and X-ray TDE samples. This IR-selected sample represents a new population of dusty TDEs that have historically been missed by optical and X-ray surveys and helps alleviate tensions between observed and theoretical TDE rates and the so-called missing energy problem.

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arXiv2023

The most luminous AGN do not produce the majority of the detected stellar-mass black hole binary mergers in the local Universe

Despite the increasing number of Gravitational Wave (GW) detections, the astrophysical origin of Binary Black Hole (BBH) mergers remains elusive. A promising formation channel for BBHs is inside accretion discs around supermassive black holes, that power Active Galactic Nuclei (AGN). In this paper, we test for the first time the spatial correlation between observed GW events and AGN. To this end, we assemble all sky catalogues with 1,412 (242) AGN with a bolometric luminosity greater than $10^{45.5} {\rm erg\ s}^{-1}$ ($10^{46}\,{\rm erg\,s}^{-1}$) with spectroscopic redshift of $z\leq0.3$ from the Milliquas catalogue, version 7.7b. These AGN are cross-matched with localisation volumes of BBH mergers observed in the same redshift range by the LIGO and Virgo interferometers during their first three observing runs. We find that the fraction of the detected mergers originated in AGN brighter than $10^{45.5}\,{\rm erg\,s}^{-1}$ ($10^{46}\,{\rm erg\,s}^{-1}$) cannot be higher than $0.49$ ($0.17$) at a 95 per cent credibility level. Our upper limits imply a limited BBH merger production efficiency of the brightest AGN, while most or all GW events may still come from lower luminosity ones. Alternatively, the AGN formation path for merging stellar-mass BBHs may be actually overall subdominant in the local Universe. To our knowledge, ours are the first observational constraints on the fractional contribution of the AGN channel to the observed BBH mergers.

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arXiv2023

Fundamental scaling relationships revealed in the optical light curves of tidal disruption events

We present fundamental scaling relationships between properties of the optical/UV light curves of tidal disruption events (TDEs) and the mass of the black hole that disrupted the star. We have uncovered these relations from the late-time emission of TDEs. Using a sample of 63 optically-selected TDEs, the latest catalog to date, we observed flattening of the early-time emission into a near-constant late-time plateau for at least two-thirds of our sources. Compared to other properties of the TDE lightcurves (e.g., peak luminosity or decay rate) the plateau luminosity shows the tightest correlation with the total mass of host galaxy ($p$-value of $2 \times 10^{-6}$, with a residual scatter of 0.3 dex). Physically this plateau stems from the presence of an accretion flow. We demonstrate theoretically and numerically that the amplitude of this plateau emission is strongly correlated with black hole mass. By simulating a large population of TDEs, we determine a plateau luminosity-black hole mass scaling relationship well described by $ \log_{10} \left(M_{\bullet}/M_{\odot} \right) = 1.50 \log_{10} \left( L_{\rm plat}/10^{43} {\rm erg \, s^{-1}} \right) + 9.0 $. The observed plateau luminosities of TDEs and black hole masses in our large sample are in excellent agreement with this simulation. Using the black hole mass predicted from the observed TDE plateau luminosity, we reproduce the well-known scaling relations between black hole mass and galaxy velocity dispersion. The large black hole masses of 10 of the TDEs in our sample allow us to provide constraints on their black hole spins, favouring rapidly rotating black holes. We add 49 (34) black hole masses to the galaxy mass (velocity dispersion) scaling relationships, updating and extending these correlations into the low black hole mass regime.

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