arXiv subjects

Mathieu Renzo

Publications and source records attributed to Mathieu Renzo.

At least 37 records · Page 2Linked to original sources

arXiv2024

Close Encounters of Wide Binaries Induced by the Galactic Tide: Implications for Stellar Mergers and Gravitational-Wave Sources

A substantial fraction of stars can be found in wide binaries with projected separations between $\sim10^2$ and $10^5\,\rm AU$. In the standard lore of binary physics, these would evolve as effectively single stars that remotely orbit one another on stationary Keplerian ellipses. However, embedded in their Galactic environment their low binding energy makes them exceptionally prone to perturbations from the gravitational potential of the Milky Way and encounters with passing stars. Employing a fully relativistic $N$-body integration scheme, we study the impact of these perturbations on the orbital evolution of wide binaries along their trajectory through the Milky Way. Our analysis reveals that the torques exerted by the Galaxy can cause large-amplitude oscillations of the binary eccentricity to $1-e\lesssim10^{-8}$. As a consequence, the wide binary members pass close to each other at periapsis, which, depending on the type of binary, potentially leads to a mass transfer or collision of stars or to an inspiral and subsequent merger of compact remnants due to gravitational-wave radiation. Based on a simulation of $10^5$ wide binaries across the Galactic field, we find that this mechanism could significantly contribute to the rate of stellar collisions and binary black hole mergers as inferred from observations of Luminous Red Novae and gravitational-wave events by LIGO/Virgo/Kagra. We conclude that the dynamics of wide binaries, despite their large mean separation, can give rise to extreme interactions between stars and compact remnants.

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arXiv2024

The Effects of $r$-Process Enrichment in Hydrogen-Rich Supernovae

Core-collapse supernovae are candidate sites for the rapid neutron capture process ($r$-process). We explore the effects of enrichment from $r$-process nuclei on the light-curves of hydrogen-rich supernovae (SNe IIP) and assess the detectability of these signatures. We modify the radiation transport code $\texttt{SNEC}$ to include the approximate effects of opacity and radioactive heating from $r$-process elements in the SN ejecta. We present models spanning a range of total $r$-process masses $M_{\rm r}$ and their assumed radial distribution within the ejecta, finding that $M_{\rm r} \gtrsim 10^{-2} M_\odot$ is sufficient to induce appreciable differences in their light-curves as compared to ordinary SNe IIP (without any $r$-process elements). The primary photometric signatures of $r$-process enrichment include a shortening of the plateau phase, coinciding with the hydrogen-recombination photosphere retreating to the $r$-process-enriched layers, and a steeper post-plateau decline associated with a reddening of the SN colors. We compare our $r$-process-enriched models to ordinary IIP models and observational data, showing that yields of $M_{\rm r} \gtrsim 10^{-2} M_\odot$ are potentially detectable across several of the metrics used by transient observers, provided that the $r$-process rich layers are mixed $\gtrsim$ halfway to the ejecta surface. This detectability threshold can roughly be reproduced analytically using a two-zone ("kilonova within a supernova") picture. Assuming that a small fraction of SNe produce a detectable $r$-process yield $M_{\rm r} \gtrsim 10^{-2}M_\odot$, and respecting constraints on the total Galactic production rate, we estimate that $\gtrsim 10^{3}-10^4$ SNe need be observed to find one $r$-enriched event, a feat that may become possible with the Vera Rubin Observatory.

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arXiv2024

Constraints on neutrino natal kicks from black-hole binary VFTS 243

The recently reported observation of VFTS 243 is the first example of a massive black-hole binary system with negligible binary interaction following black-hole formation. The black-hole mass ($\approx 10\ M_{\odot}$) and near-circular orbit ($e\approx 0.02$) of VFTS 243 suggest that the progenitor star experienced complete collapse, with energy-momentum being lost predominantly through neutrinos. VFTS 243 enables us to constrain the natal kick and neutrino-emission asymmetry during black-hole formation. At 68% C.L., the natal kick velocity (mass decrement) is $\lesssim 10$ km/s ($\lesssim 1.0\ M_{\odot}$), with a full probability distribution that peaks when $\approx 0.3\ M_{\odot}$ were ejected, presumably in neutrinos, and the black hole experienced a natal kick of $4$ km/s. The neutrino-emission asymmetry is $\lesssim 4$%, with best fit values of $\sim$0-0.2%. Such a small neutrino natal kick accompanying black-hole formation is in agreement with theoretical predictions.

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arXiv2024

The Asteroseismic Imprints of Mass Transfer: A Case Study of a Binary Mass Gainer in the SPB Instability Strip

We present new simulations investigating the impact of mass transfer on the asteroseismic signals of slowly pulsating B stars. We use MESA to simulate the evolution of a binary star system and GYRE to compute the asteroseismic properties of the accretor star. We show that, compared to a single star of the same final mass, a star that has undergone accretion (of non-enriched material) has a significantly different internal structure, evident in both the hydrogen abundance profile and Brunt-Väisälä frequency profile. These differences result in significant changes in the observed period spacing patterns, implying that one may use this as a diagnostic to test whether a star's core has been rejuvenated as a result of accretion. We show that it is essential to consider the full multimodal posterior distributions when fitting stellar properties of mass-gainers to avoid drawing misleading conclusions. Even with these considerations, stellar ages will be significantly underestimated when assuming single star evolution for a mass-gainer. We find that future detectors with improved uncertainties would rule out single star models with the correct mass and central hydrogen fraction. Our proof of principle analysis demonstrates the need to further investigate the impact of binary interactions on stellar asteroseismic signals for a wide range of parameters, such as initial mass, amount of mass transferred and the age of the accretor star at the onset of mass transfer.

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arXiv2023

Modelling time-dependent convective penetration in 1D stellar evolution

1D stellar evolution calculations produce uncertain predictions for quantities like the age, core mass, core compactness, and nucleo-synthetic yields; a key source of uncertainty is the modeling of interfaces between regions that are convectively stable and those that are not. Theoretical and numerical work has demonstrated that there should be numerous processes adjacent to the convective boundary that induce chemical and angular momentum transport, as well as modify the thermal structure of the star. One such process is called convective penetration, wherein vigorous convection extends beyond the nominal convective boundary and alters both the composition and thermal structure. In this work, we incorporate the process of convective penetration in stellar evolution calculations using the stellar evolution software instrument mesa. We implement convective penetration according to the description presented by Anders et al. (2022a) to calculate a grid of models from the pre main sequence to He core depletion. The extent of the convective penetration zone is self-consistently calculated at each time step without introducing new free parameters. We find both a substantial penetration zone in all models with a convective core and observable differences to global stellar properties such as the luminosity and radius. We preset how the predicted radial extent of the penetration zone scales with the total stellar mass, age and the metallicity of the star. We discuss our results in the context of existing numerical and observational studies.

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arXiv2022

Resolving The Peak Of The Black Hole Mass Spectrum

Gravitational wave (GW) detections of binary black hole (BH) mergers have begun to sample the cosmic BH mass distribution. The evolution of single stellar cores predicts a gap in the BH mass distribution due to pair-instability supernova (PISN). Determining the upper and lower edges of the BH mass gap can be useful for interpreting GW detections from merging BHs. We use \MESA\ to evolve single, non-rotating, massive helium cores with a metallicity of $Z = 10^{-5}$ until they either collapse to form a BH or explode as a PISN without leaving a compact remnant. We calculate the boundaries of the lower BH mass gap for S-factors in the range S(300 keV) = (77,203) keV b, corresponding to the $\pm 3σ$ uncertainty in our high resolution tabulated $^{12}$C($α$,$γ$)$^{16}$O reaction rate probability distribution function. We extensively test the temporal and mass resolution to resolve the theoretical peak of the BH mass spectrum across the BH mass gap. We explore the convergence with respect to convective mixing and nuclear burning, finding that significant time resolution is needed to achieve convergence. We also test adopting a minimum diffusion coefficient to help lower resolution models reach convergence. We establish a new lower edge of the upper mass gap as M\textsubscript{lower} $\simeq$\,60$^{+32}_{-14}$\,\Msun\ from the $\pm 3σ$ uncertainty in the $^{12}\text{C}(α, γ) ^{16}\text{O}$ rate. We explore the effect of a larger 3-$α$ rate on the lower edge of the upper mass gap, finding M\textsubscript{lower} $\simeq$\,69$^{+34}_{-18}$\,\Msun. We compare our results with BHs reported in the Gravitational-Wave Transient Catalog.

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arXiv2022

Successful Common Envelope Ejection and Binary Neutron Star Formation in 3D Hydrodynamics

A binary neutron star merger has been observed in a multi-messenger detection of gravitational wave (GW) and electromagnetic (EM) radiation. Binary neutron stars that merge within a Hubble time, as well as many other compact binaries, are expected to form via common envelope evolution. Yet five decades of research on common envelope evolution have not yet resulted in a satisfactory understanding of the multi-spatial multi-timescale evolution for the systems that lead to compact binaries. In this paper, we report on the first successful simulations of common envelope ejection leading to binary neutron star formation in 3D hydrodynamics. We simulate the dynamical inspiral phase of the interaction between a 12$M_\odot$ red supergiant and a 1.4$M_\odot$ neutron star for different initial separations and initial conditions. For all of our simulations, we find complete envelope ejection and final orbital separations of $a_{\rm f} \approx 1.3$-$5.1 R_\odot$ depending on the simulation and criterion, leading to binary neutron stars that can merge within a Hubble time. We find $α_{\rm CE}$-equivalent efficiencies of $\approx 0.1$-$2.7$ depending on the simulation and criterion, but this may be specific for these extended progenitors. We fully resolve the core of the star to $\lesssim 0.005 R_\odot$ and our 3D hydrodynamics simulations are informed by an adjusted 1D analytic energy formalism and a 2D kinematics study in order to overcome the prohibitive computational cost of simulating these systems. The framework we develop in this paper can be used to simulate a wide variety of interactions between stars, from stellar mergers to common envelope episodes leading to GW sources.

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arXiv2022

Dissecting the microphysics behind the metallicity-dependence of massive stars radii

Understanding the radii of massive stars throughout their evolution is important to answering numerous questions about stellar physics, from binary interactions on the main sequence to the pre-supernova radii. One important factor determining a star's radius is the fraction of its mass in elements heavier than Helium (metallicity, $Z$). However, the metallicity enters stellar evolution through several distinct microphysical processes, and which dominates can change throughout stellar evolution and with the overall magnitude of $Z$. We perform a series of numerical experiments with 15M$_{\odot}$ MESA models computed doubling separately the metallicity entering the radiative opacity, the equation of state, and the nuclear reaction network to isolate the impact of each on stellar radii. We explore separately models centered around two metallicity values: one near solar $Z=0.02$ and another sub-solar $Z\sim10^{-3}$, and consider several key epochs from the end of the main sequence to core carbon depletion. We find that the metallicity entering the opacity dominates at most epochs for the solar metallicity models, contributing to on average $\sim$60 - 90% of the total change in stellar radius. Nuclear reactions have a larger impact ($\sim$50 - 70%) during most epochs in the subsolar $Z$ models. The methodology introduced here can be employed more generally to propagate known microphysics errors into uncertainties on macrophysical observables including stellar radii.

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arXiv2022

SNR G292.0+1.8: A Remnant of a Low-Mass Progenitor Stripped-Envelope Supernova

We present a study of the Galactic supernova remnant (SNR) G292.0+1.8, a classic example of a core-collapse SNR that contains oxygen-rich ejecta, circumstellar material, a rapidly moving pulsar, and a pulsar wind nebula (PWN). We use hydrodynamic simulations of the remnant evolution to show that the SNR reverse shock is interacting with the PWN and has most likely shocked the majority of supernova ejecta. In our models, such a scenario requires a total ejecta mass of $\lesssim 3\: \rm M_{\odot}$ and implies that there is no significant quantity of cold ejecta in the interior of the reverse shock. In light of these results, we compare the estimated elemental masses and abundance ratios in the reverse-shocked ejecta to nucleosynthesis models and find that they are consistent with a progenitor star with an initial mass of 12-16 $\: \rm M_{\odot}$. We conclude that the progenitor of G292.0+1.8 was likely a relatively low mass star that experienced significant mass loss through a binary interaction and would have produced a stripped-envelope supernova explosion. We also argue that the region known as the "spur" in G292.0+1.8 arises as a result of the pulsar's motion through the supernova ejecta and that its dynamical properties may suggest a line-of-sight component to the pulsar's velocity, leading to a total space velocity of $\sim 600\: \rm km\:s^{-1}$ and implying a significant natal kick. Finally, we discuss binary mass loss scenarios relevant to G292.0+1.8 and their implications for the binary companion properties and future searches.

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arXiv2021

Searching for Anomalies in the ZTF Catalog of Periodic Variable Stars

Periodic variables illuminate the physical processes of stars throughout their lifetime. Wide-field surveys continue to increase our discovery rates of periodic variable stars. Automated approaches are essential to identify interesting periodic variable stars for multi-wavelength and spectroscopic follow-up. Here, we present a novel unsupervised machine learning approach to hunt for anomalous periodic variables using phase-folded light curves presented in the Zwicky Transient Facility Catalogue of Periodic Variable Stars by \citet{Chen_2020}. We use a convolutional variational autoencoder to learn a low dimensional latent representation, and we search for anomalies within this latent dimension via an isolation forest. We identify anomalies with irregular variability. Most of the top anomalies are likely highly variable Red Giants or Asymptotic Giant Branch stars concentrated in the Milky Way galactic disk; a fraction of the identified anomalies are more consistent with Young Stellar Objects. Detailed spectroscopic follow-up observations are encouraged to reveal the nature of these anomalies.

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arXiv2021

"Super-Kilonovae" from Massive Collapsars as Signatures of Black-Hole Birth in the Pair-instability Mass Gap

The core collapse of rapidly rotating massive ~10 Msun stars ("collapsars"), and resulting formation of hyper-accreting black holes, are a leading model for the central engines of long-duration gamma-ray bursts (GRB) and promising sources of r-process nucleosynthesis. Here, we explore the signatures of collapsars from progenitors with extremely massive helium cores >130 Msun above the pair-instability mass gap. While rapid collapse to a black hole likely precludes a prompt explosion in these systems, we demonstrate that disk outflows can generate a large quantity (up to >50 Msun) of ejecta, comprised of >5-10 Msun in r-process elements and ~0.1-1 Msun of $^{56}$Ni, expanding at velocities ~0.1c. Radioactive heating of the disk-wind ejecta powers an optical/infrared transient, with a characteristic luminosity $\sim 10^{42}$ erg s$^{-1}$ and spectral peak in the near-infrared (due to the high optical/UV opacities of lanthanide elements) similar to kilonovae from neutron star mergers, but with longer durations $\gtrsim$ 1 month. These "super-kilonovae" (superKNe) herald the birth of massive black holes >60 Msun, which, as a result of disk wind mass-loss, can populate the pair-instability mass gap 'from above' and could potentially create the binary components of GW190521. SuperKNe could be discovered via wide-field surveys such as those planned with the Roman Space Telescope or via late-time infrared follow-up observations of extremely energetic GRBs. Gravitational waves of frequency ~0.1-50 Hz from non-axisymmetric instabilities in self-gravitating massive collapsar disks are potentially detectable by proposed third-generation intermediate and high-frequency observatories at distances up to hundreds of Mpc; in contrast to the "chirp" from binary mergers, the collapsar gravitational-wave signal decreases in frequency as the disk radius grows ("sad trombone").

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arXiv2021

Confirming NGC 6231 as the parent cluster of the runaway high-mass X-ray binary HD 153919/4U 1700-37 with Gaia DR2

A significant fraction of the most massive stars move through space with a high velocity. One of the possible physical explanations is that a supernova in a compact binary system results in a high recoil velocity of the system. If the system remains bound, it can be subsequently observed as a spectroscopic binary (SB1), a high-mass X-ray binary, a compact binary, and finally a gravitational-wave event. If such a system is traced back to its parent cluster, binary evolution models can be tested in great detail. The Gaia proper motions and parallaxes are used to demonstrate that the high-mass X-ray binary HD153919/4U 1700-37 originates from NGC6231, the nucleus of the OB association Sco OB1. The O supergiant and its compact companion, of which the physical nature (a neutron star or a black hole) is unknown, move with a space velocity of 63 km/s with respect to NGC6231. The kinematical age of the system is 2.2 Myr. The parallaxes and accurate proper motions in Gaia DR2 were used to perform a membership analysis of NGC 6231. The distance to NGC6231 is 1.63 kpc. Isochrone fitting results in an age of 4.7 Myr. With the identification of NGC6231 as the parent cluster, the upper limit on the age of the progenitor of 4U1700-37 at the moment of the supernova explosion is 3.0 Myr. With these constraints, the evolutionary history of the system can be reconstructed with an initial mass of the progenitor of the compact object >60 Msun. Given its current high space velocity and the derived evolutionary history, the compact object in the system is more likely to have received a large natal kick, which suggests that it is more likely a neutron star than a black hole. HD153919/4U1700-37 might be a prototype in the Milky Way for the progenitor of gravitational wave events such as GW190412

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arXiv2021

Periodic Fast Radio Bursts from Luminous X-ray Binaries

The discovery of periodicity in the arrival times of the fast radio bursts (FRBs) poses a challenge to the oft-studied magnetar scenarios. However, models that postulate that FRBs result from magnetized shocks or magnetic reconnection in a relativistic outflow are not specific to magnetar engines; instead, they require only the impulsive injection of relativistic energy into a dense magnetized medium. Motivated thus, we outline a new scenario in which FRBs are powered by short-lived relativistic outflows (``flares'') from accreting black holes or neutron stars, which propagate into the cavity of the pre-existing (``quiescent'') jet. In order to reproduce FRB luminosities and rates, we are driven to consider binaries of stellar-mass compact objects undergoing super-Eddington mass-transfer, similar to ultraluminous X-ray (ULX) sources. Indeed, the host galaxies of FRBs, and their spatial offsets within their hosts, show broad similarities with ULXs. Periodicity on timescales of days to years could be attributed to precession (e.g., Lens-Thirring) of the polar accretion funnel, along which the FRB emission is geometrically and relativistically beamed, which sweeps across the observer line of sight. Accounting for the most luminous FRBs via accretion power may require a population of binaries undergoing brief-lived phases of unstable (dynamical-timescale) mass-transfer. This will lead to secular evolution in the properties of some repeating FRBs on timescales of months to years, followed by a transient optical/IR counterpart akin to a luminous red nova, or a more luminous accretion-powered optical/X-ray transient. We encourage targeted FRB searches of known ULX sources.

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arXiv2021

Binary-Stripped Stars as Core-Collapse Supernovae Progenitors

Most massive stars experience binary interactions in their lifetimes that can alter both the surface and core structure of the stripped star with significant effects on their ultimate fate as core-collapse supernovae. However, core-collapse supernovae simulations to date have focused almost exclusively on the evolution of single stars. We present a systematic simulation study of single and binary-stripped stars with the same initial mass as candidates for core-collapse supernovae (11 - 21 M$_{\odot}$). Generally, we find that binary-stripped stars core tend to be less compact, with a more prominent, deeper silicon/oxygen interface, and explode preferentially to the corresponding single stars of the same initial mass. Such a dichotomy of behavior between these two modes of evolution would have important implications for supernovae statistics, including the final neutron star masses, explosion energies, and nucleosynthetic yields. Binary-stripped remnants are also well poised to populate the possible mass gap between the heaviest neutron stars and the lightest black holes. Our work presents an improvement along two fronts, as we self-consistently account for the pre-collapse stellar evolution and the subsequent explosion outcome. Even so, our results emphasize the need for more detailed stellar evolutionary models to capture the sensitive nature of explosion outcome.

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arXiv2020

Effect of binary evolution on the inferred initial and final core masses of hydrogen-rich, Type~II supernova progenitors

The majority of massive stars, the progenitors of core-collapse supernovae (SNe), are found in close binary systems. Zapartas et al. (2019) modeled the fraction of hydrogen-rich, Type II SN progenitors which have their evolution affected by mass exchange with their companion, finding this to be between 1/3 and 1/2 for most assumptions. Here we study in more depth the impact of this binary history of Type II SN progenitors on their final pre-SN core mass distribution, using population synthesis simulations. We find that binary star progenitors of Type II SNe typically end their life with a larger core mass than they would have had if they had lived in isolation, because they gained mass or merged with a companion before explosion. The combination of the diverse binary evolutionary paths typically lead to a marginally shallower final core mass distribution. Discussing our results in the context of the red supergiant problem, i.e., the reported lack of detected high luminosity progenitors, we conclude that binary evolution does not seem to significantly affect the issue. This conclusion is quite robust against our variations in the assumptions of binary physics. We also predict that inferring the initial masses of Type II SN progenitors from "age-dating" its surrounding environment systematically yields lower masses compared to methods that probe the pre-SN core mass or luminosity. A robust discrepancy between the inferred initial masses of a SN progenitor from those different techniques could indicate an evolutionary history of binary mass accretion or merging.

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arXiv2020

Constraints from gravitational wave detections of binary black hole mergers on the $^{12}\rm{C}\left(α,γ\right)^{16}\!\rm{O}$ rate

Gravitational wave detections are starting to allow us to probe the physical processes in the evolution of very massive stars through the imprints they leave on their final remnants. Stellar evolution theory predicts the existence of a gap in the black hole mass distribution at high mass due to the effects of pair-instability. Previously, we showed that the location of the gap is robust against model uncertainties, but it does depend sensitively on the uncertain $^{12}\rm{C}\left(α,γ\right)^{16}\!\rm{O}$ rate. This rate is of great astrophysical significance and governs the production of oxygen at the expense of carbon. We use the open source MESA stellar evolution code to evolve massive helium stars to probe the location of the mass gap. We find that the maximum black hole mass below the gap varies between $40\rm{M}_\odot$ to $90\rm{M}_\odot$, depending on the strength of the uncertain $^{12}\rm{C}\left(α,γ\right)^{16}\!\rm{O}$ reaction rate. With the first ten gravitational-wave detections of black holes, we constrain the astrophysical S-factor for $^{12}\rm{C}\left(α,γ\right)^{16}\!\rm{O}$, at $300\rm{keV}$, to $S_{300}>175\rm{\,keV\, barns}$ at 68% confidence. With $\mathcal{O}(50)$ detected binary black hole mergers, we expect to constrain the S-factor to within $\pm10$-$30\rm{\,keV\, barns}$. We also highlight a role for independent constraints from electromagnetic transient surveys. The unambiguous detection of pulsational pair instability supernovae would imply that $S_{300}>79\rm{\,keV\, barns}$. Degeneracies with other model uncertainties need to be investigated further, but probing nuclear stellar astrophysics poses a promising science case for the future gravitational wave detectors.

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arXiv2020

Core-Collapse Supernovae in Binaries as the Origin of Galactic Hyper-Runaway Stars

Several stars detected moving at velocities near to or exceeding the Galactic escape speed likely originated in the Milky Way disc. We quantitatively explore the `binary supernova scenario' hypothesis, wherein these `hyper-runaway' stars are ejected at large peculiar velocities when their close, massive binary companions undergo a core-collapse supernova and the binary is disrupted. We perform an extensive suite of binary population synthesis simulations evolving massive systems to determine the assumptions and parameters which most impact the ejection rate of fast stars. In a simulation tailored to eject fast stars, we find the most likely hyper-runaway star progenitor binary is composed of a massive ($\sim$$30\,\mathrm{M_{\odot}}$) primary and a $\sim$$3-4\,\mathrm{M_{\odot}}$ companion on an orbital period that shrinks to $\lesssim$1 day prior to the core collapse following a common envelope phase. The black hole remnant formed from the primary must receive a natal kick $\gtrsim$1000 $\mathrm{km\ s^{-1}}$ to disrupt the binary and eject the companion at a large velocity. We compare the fast stars produced in these simulations to a contemporary census of early-type Milky Way hyper-runaway star candidates. We find that these rare objects may be produced in sufficient number only when poorly-constrained binary evolution parameters related to the strength of post-core collapse remnant natal kicks and common envelope efficiency are adjusted to values currently unsupported -- but not excluded -- by the literature. We discuss observational implications that may constrain the existence of these putative progenitor systems.

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arXiv2020

Pulsational pair-instability supernovae in very close binaries

Pair-instability and pulsational pair-instability supernovae (PPISN) have not been unambiguously observed so far. They are, however, promising candidates for the progenitors of the heaviest binary black hole (BBH) mergers detected. If these BBHs are the product of binary evolution, then PPISNe could occur in very close binaries. Motivated by this, we discuss the implications of a PPISN happening with a close binary companion, and what impact these events have on the formation of merging BBHs through binary evolution. For this, we have computed a set of models of metal-poor ($Z_\odot/10$) single helium stars using the \texttt{MESA} software instrument. For PPISN progenitors with pre-pulse masses $>50M_\odot$ we find that, after a pulse, heat deposited throughout the layers of the star that remain bound cause it to expand to more than $100R_\odot$ for periods of $10^2-10^4\;$~yrs depending on the mass of the progenitor. This results in long-lived phases of Roche-lobe overflow or even common-envelope events if there is a close binary companion, leading to additional electromagnetic transients associated to PPISN eruptions. If we ignore the effect of these interactions, we find that mass loss from PPISNe reduces the final black hole spin by $\sim 30\%$, induces eccentricities below the threshold of detectability of the LISA observatory, and can produce a double-peaked distribution of measured chirp masses in BBH mergers observed by ground-based detectors.

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