--- _id: '17529' abstract: - lang: eng text: The astrophysical origin of gravitational wave (GW) events is one of the most timely problems in the wake of the LIGO/Virgo discoveries. In active galactic nuclei (AGN), binaries form and evolve efficiently by dynamical interactions and gaseous dissipation. Previous studies have suggested that binary black hole (BBH) mergers in AGN disks can contribute significantly to BBH mergers observed by GW interferometers. Here we examine the distribution of the effective spin parameter χeff of this GW source population. We extend our semi-analytical model of binary formation and evolution in AGN disks by following the evolution of the binary orbital angular momenta and black hole (BH) spins. BH spins change due to gas accretion and BH mergers, while the binary orbital angular momenta evolve due to gas accretion and binary-single interactions. We find that the distribution of χeff predicted by our AGN model is similar to the distribution observed during LIGO/Virgo O1 and O2. On the other hand, if radial migration of BHs is inefficient, χeff is skewed toward higher values compared with the observed distribution, because of the paucity of scattering events that would randomize spin directions relative to the orbital plane. We suggest that high binary masses and the positive correlation between binary mass and the standard deviation of χeff for chirp masses up to ≈20 M⊙, can be possible signatures for mergers originating in AGN disks. Finally, hierarchical mergers in AGN disks naturally produce properties of the recent GW event GW190412, including a low mass ratio, a high primary BH spin, and a significant spin component in the orbital plane. article_number: '26' article_processing_charge: No article_type: original author: - first_name: Hiromichi full_name: Tagawa, Hiromichi last_name: Tagawa - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Imre full_name: Bartos, Imre last_name: Bartos - first_name: Bence full_name: Kocsis, Bence last_name: Kocsis citation: ama: Tagawa H, Haiman Z, Bartos I, Kocsis B. Spin evolution of stellar-mass black hole binaries in active galactic nuclei. The Astrophysical Journal. 2020;899(1). doi:10.3847/1538-4357/aba2cc apa: Tagawa, H., Haiman, Z., Bartos, I., & Kocsis, B. (2020). Spin evolution of stellar-mass black hole binaries in active galactic nuclei. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/aba2cc chicago: Tagawa, Hiromichi, Zoltán Haiman, Imre Bartos, and Bence Kocsis. “Spin Evolution of Stellar-Mass Black Hole Binaries in Active Galactic Nuclei.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/aba2cc. ieee: H. Tagawa, Z. Haiman, I. Bartos, and B. Kocsis, “Spin evolution of stellar-mass black hole binaries in active galactic nuclei,” The Astrophysical Journal, vol. 899, no. 1. American Astronomical Society, 2020. ista: Tagawa H, Haiman Z, Bartos I, Kocsis B. 2020. Spin evolution of stellar-mass black hole binaries in active galactic nuclei. The Astrophysical Journal. 899(1), 26. mla: Tagawa, Hiromichi, et al. “Spin Evolution of Stellar-Mass Black Hole Binaries in Active Galactic Nuclei.” The Astrophysical Journal, vol. 899, no. 1, 26, American Astronomical Society, 2020, doi:10.3847/1538-4357/aba2cc. short: H. Tagawa, Z. Haiman, I. Bartos, B. Kocsis, The Astrophysical Journal 899 (2020). date_created: 2024-09-05T09:36:37Z date_published: 2020-08-10T00:00:00Z date_updated: 2024-09-11T09:11:55Z day: '10' doi: 10.3847/1538-4357/aba2cc extern: '1' intvolume: ' 899' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3847/1538-4357/aba2cc month: '08' oa: 1 oa_version: Published Version publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Spin evolution of stellar-mass black hole binaries in active galactic nuclei type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 899 year: '2020' ... --- _id: '17537' abstract: - lang: eng text: The recent gravitational wave merger event, GW190521, has challenged our understanding of the stellar-mass black hole (BH) formation. The primary and secondary BH are both inferred to fall inside the pair-instability (PI) mass gap. Here we propose that the formation of such binaries is possible through gas accretion onto the BH remnants of Population III (Pop~III) stars born in high-redshift (z>10) minihalos. Once the parent halo has grown to the atomic-cooling limit, even brief episodes of gas accretion in the dense central regions of the halo can increase the masses of Pop~III remnant BHs above the PI limit. Starting with a BBH with an initial mass of O(100) M⊙ we find that it would only need to spend about 100~Myr in the inner few pc of an atomic-cooling halo to accrete about 50~M⊙ of material and resemble a system similar to GW190521. The dynamical friction timescale for the binary to sink to the dense inner region of its parent halo is comparable or shorter than the accretion timescale required to increase their mass above the PI limit. Once in the core of the halo, the binary can enter a phase of hyper-Eddington accretion, where it would only take a few thousand years to exceed the PI limit through accretion. Even more massive BBHs could form through this channel, and be detectable by detectors with improved low-frequency sensitivity. Single Pop~III BH remnants would also grow through accretion and could later form binaries dynamically. As little as a few percent of Pop~III BH remnants may be sufficient to match the rate of massive BBH mergers inferred from GW190521 of 0.13+0.3−0.11Gpc−3yr−1. article_number: L21 article_processing_charge: No article_type: original author: - first_name: Mohammadtaher full_name: Safarzadeh, Mohammadtaher last_name: Safarzadeh - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Safarzadeh M, Haiman Z. Formation of GW190521 via gas accretion onto population III stellar black hole remnants born in high-redshift minihalos. The Astrophysical Journal Letters. 2020;903(1). doi:10.3847/2041-8213/abc253 apa: Safarzadeh, M., & Haiman, Z. (2020). Formation of GW190521 via gas accretion onto population III stellar black hole remnants born in high-redshift minihalos. The Astrophysical Journal Letters. American Astronomical Society. https://doi.org/10.3847/2041-8213/abc253 chicago: Safarzadeh, Mohammadtaher, and Zoltán Haiman. “Formation of GW190521 via Gas Accretion onto Population III Stellar Black Hole Remnants Born in High-Redshift Minihalos.” The Astrophysical Journal Letters. American Astronomical Society, 2020. https://doi.org/10.3847/2041-8213/abc253. ieee: M. Safarzadeh and Z. Haiman, “Formation of GW190521 via gas accretion onto population III stellar black hole remnants born in high-redshift minihalos,” The Astrophysical Journal Letters, vol. 903, no. 1. American Astronomical Society, 2020. ista: Safarzadeh M, Haiman Z. 2020. Formation of GW190521 via gas accretion onto population III stellar black hole remnants born in high-redshift minihalos. The Astrophysical Journal Letters. 903(1), L21. mla: Safarzadeh, Mohammadtaher, and Zoltán Haiman. “Formation of GW190521 via Gas Accretion onto Population III Stellar Black Hole Remnants Born in High-Redshift Minihalos.” The Astrophysical Journal Letters, vol. 903, no. 1, L21, American Astronomical Society, 2020, doi:10.3847/2041-8213/abc253. short: M. Safarzadeh, Z. Haiman, The Astrophysical Journal Letters 903 (2020). date_created: 2024-09-05T09:50:29Z date_published: 2020-11-02T00:00:00Z date_updated: 2024-09-12T09:33:05Z day: '02' doi: 10.3847/2041-8213/abc253 extern: '1' intvolume: ' 903' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3847/2041-8213/abc253 month: '11' oa: 1 oa_version: Published Version publication: The Astrophysical Journal Letters publication_identifier: issn: - 2041-8205 - 2041-8213 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Formation of GW190521 via gas accretion onto population III stellar black hole remnants born in high-redshift minihalos type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 903 year: '2020' ... --- _id: '17538' abstract: - lang: eng text: Recent three-dimensional cosmological simulations of protogalaxy formation have suggested that supermassive stars (SMSs) can form in gas clouds in which H2 cooling is suppressed by dynamical heating prior to the activation of atomic cooling (Wise et al. 2019), but they stopped short of the following growth of a central protostar. Here we examine whether accretion on the protostellar core in this cloud is sufficiently rapid, in the face of the radiation feedback, to produce a SMS. We perform one-dimensional radiation-hydrodynamical simulations of the hot collapsing cloud with non-equilibrium chemical reactions directly adopting the cloud properties from Wise et al. (2019) as an initial condition. We find that the stellar Lyman-Werner (LW) radiation from the SMS dissociates H2 in the inner regions of the gas flow, increasing gas temperature and thermal pressure, and temporarily stopping the accretion. However, this negative feedback ceases when the self-gravity and inward ram pressure force on larger scales push the gas inward. The central protostar is unable to expand an HII region due to the high density, and grows to a mass of ≳105M⊙. Our results suggests the successful formation of SMSs, and resulting massive (∼105M⊙) remnant black holes in the clouds, but need to be confirmed in two- or three-dimensional simulations. article_processing_charge: No article_type: original author: - first_name: Yuya full_name: Sakurai, Yuya last_name: Sakurai - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Kohei full_name: Inayoshi, Kohei last_name: Inayoshi citation: ama: Sakurai Y, Haiman Z, Inayoshi K. Radiative feedback for supermassive star formation in a massive cloud with H2 molecules in an atomic-cooling halo. Monthly Notices of the Royal Astronomical Society. 2020;499(4):5960-5971. doi:10.1093/mnras/staa3227 apa: Sakurai, Y., Haiman, Z., & Inayoshi, K. (2020). Radiative feedback for supermassive star formation in a massive cloud with H2 molecules in an atomic-cooling halo. Monthly Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/staa3227 chicago: Sakurai, Yuya, Zoltán Haiman, and Kohei Inayoshi. “Radiative Feedback for Supermassive Star Formation in a Massive Cloud with H2 Molecules in an Atomic-Cooling Halo.” Monthly Notices of the Royal Astronomical Society. Oxford University Press, 2020. https://doi.org/10.1093/mnras/staa3227. ieee: Y. Sakurai, Z. Haiman, and K. Inayoshi, “Radiative feedback for supermassive star formation in a massive cloud with H2 molecules in an atomic-cooling halo,” Monthly Notices of the Royal Astronomical Society, vol. 499, no. 4. Oxford University Press, pp. 5960–5971, 2020. ista: Sakurai Y, Haiman Z, Inayoshi K. 2020. Radiative feedback for supermassive star formation in a massive cloud with H2 molecules in an atomic-cooling halo. Monthly Notices of the Royal Astronomical Society. 499(4), 5960–5971. mla: Sakurai, Yuya, et al. “Radiative Feedback for Supermassive Star Formation in a Massive Cloud with H2 Molecules in an Atomic-Cooling Halo.” Monthly Notices of the Royal Astronomical Society, vol. 499, no. 4, Oxford University Press, 2020, pp. 5960–71, doi:10.1093/mnras/staa3227. short: Y. Sakurai, Z. Haiman, K. Inayoshi, Monthly Notices of the Royal Astronomical Society 499 (2020) 5960–5971. date_created: 2024-09-05T09:51:17Z date_published: 2020-10-17T00:00:00Z date_updated: 2024-09-12T09:39:27Z day: '17' doi: 10.1093/mnras/staa3227 extern: '1' intvolume: ' 499' issue: '4' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1093/mnras/staa3227 month: '10' oa: 1 oa_version: Published Version page: 5960-5971 publication: Monthly Notices of the Royal Astronomical Society publication_identifier: issn: - 0035-8711 - 1365-2966 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: Radiative feedback for supermassive star formation in a massive cloud with H2 molecules in an atomic-cooling halo type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 499 year: '2020' ... --- _id: '17540' abstract: - lang: eng text: Among the potential milliHz gravitational wave (GW) sources for the upcoming space-based interferometer LISA are extreme- or intermediate-mass ratio inspirals (EMRI/IMRIs). These events involve the coalescence of supermassive black holes in the mass range 105M⊙≲M≲107M⊙ with companion BHs of much lower masses. A subset of E/IMRIs are expected to occur in the accretion discs of active galactic nuclei (AGN), where torques exerted by the disc can interfere with the inspiral and cause a phase shift in the GW waveform. Here we use a suite of two-dimensional hydrodynamical simulations with the moving-mesh code DISCO to present a systematic study of disc torques. We measure torques on an inspiraling BH and compute the corresponding waveform deviations as a function of the binary mass ratio q≡M2/M1, the disc viscosity (α), and gas temperature (or equivalently Mach number; M). We find that the absolute value of the gas torques is within an order of magnitude of previously determined planetary migration torques, but their precise value and sign depends non-trivially on the combination of these parameters. The gas imprint is detectable by LISA for binaries embedded in AGN discs with surface densities above Σ0≥104−6gcm−2, depending on q, α and M. Deviations are most pronounced in discs with higher viscosities, and for E/IMRIs detected at frequencies where LISA is most sensitive. Torques in colder discs exhibit a noticeable dependence on the GW-driven inspiral rate as well as strong fluctuations at late stages of the inspiral. Our results further suggest that LISA may be able to place constraints on AGN disc parameters and the physics of disc-satellite interaction. article_processing_charge: No article_type: original author: - first_name: A full_name: Derdzinski, A last_name: Derdzinski - first_name: D full_name: D’Orazio, D last_name: D’Orazio - first_name: P full_name: Duffell, P last_name: Duffell - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: A full_name: MacFadyen, A last_name: MacFadyen citation: ama: Derdzinski A, D’Orazio D, Duffell P, Haiman Z, MacFadyen A. Evolution of gas disc–embedded intermediate mass ratio inspirals in the LISA band. Monthly Notices of the Royal Astronomical Society. 2020;501(3):3540-3557. doi:10.1093/mnras/staa3976 apa: Derdzinski, A., D’Orazio, D., Duffell, P., Haiman, Z., & MacFadyen, A. (2020). Evolution of gas disc–embedded intermediate mass ratio inspirals in the LISA band. Monthly Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/staa3976 chicago: Derdzinski, A, D D’Orazio, P Duffell, Zoltán Haiman, and A MacFadyen. “Evolution of Gas Disc–Embedded Intermediate Mass Ratio Inspirals in the LISA Band.” Monthly Notices of the Royal Astronomical Society. Oxford University Press, 2020. https://doi.org/10.1093/mnras/staa3976. ieee: A. Derdzinski, D. D’Orazio, P. Duffell, Z. Haiman, and A. MacFadyen, “Evolution of gas disc–embedded intermediate mass ratio inspirals in the LISA band,” Monthly Notices of the Royal Astronomical Society, vol. 501, no. 3. Oxford University Press, pp. 3540–3557, 2020. ista: Derdzinski A, D’Orazio D, Duffell P, Haiman Z, MacFadyen A. 2020. Evolution of gas disc–embedded intermediate mass ratio inspirals in the LISA band. Monthly Notices of the Royal Astronomical Society. 501(3), 3540–3557. mla: Derdzinski, A., et al. “Evolution of Gas Disc–Embedded Intermediate Mass Ratio Inspirals in the LISA Band.” Monthly Notices of the Royal Astronomical Society, vol. 501, no. 3, Oxford University Press, 2020, pp. 3540–57, doi:10.1093/mnras/staa3976. short: A. Derdzinski, D. D’Orazio, P. Duffell, Z. Haiman, A. MacFadyen, Monthly Notices of the Royal Astronomical Society 501 (2020) 3540–3557. date_created: 2024-09-05T09:55:24Z date_published: 2020-12-29T00:00:00Z date_updated: 2024-09-12T09:54:26Z day: '29' doi: 10.1093/mnras/staa3976 extern: '1' intvolume: ' 501' issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1093/mnras/staa3976 month: '12' oa: 1 oa_version: Published Version page: 3540-3557 publication: Monthly Notices of the Royal Astronomical Society publication_identifier: issn: - 0035-8711 - 1365-2966 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: Evolution of gas disc–embedded intermediate mass ratio inspirals in the LISA band type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 501 year: '2020' ... --- _id: '17542' abstract: - lang: eng text: 'We present a new semianalytic model of the formation of the first stars. Our method takes dark matter halo merger trees (including three-dimensional spatial information) from cosmological N-body simulations as input and applies analytic prescriptions to compute both the Population III and metal-enriched star formation histories. We have developed a novel method to accurately compute the major feedback processes affecting Population III star formation: H2 photodissociation from Lyman–Werner (LW) radiation, suppression of star formation due to inhomogeneous reionization, and metal enrichment via supernova winds. Our method utilizes a grid-based approach relying on fast Fourier transforms to rapidly track the LW intensity, ionization fraction, and metallicity in three dimensions throughout the simulation box. We present simulations for a wide range of astrophysical model parameters from z ≈ 30 to 6. Initially long-range LW feedback and local metal enrichment and reionization feedback dominate. However, for z ≲ 15 we find that the star formation rate density (SFRD) of Population III stars is impacted by the combination of external metal enrichment (metals from one halo polluting other pristine halos) and inhomogeneous reionization. We find that the interplay of these processes is particularly important for the Population III SFRD at z ≲ 10. Reionization feedback delays star formation long enough for metal bubbles to reach halos that would otherwise form Population III stars. Including these effects can lead to more than an order-of-magnitude decrease in the Population III SFRD at z = 6 compared to LW feedback alone.' article_number: '95' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Eli full_name: Visbal, Eli last_name: Visbal - first_name: Greg L. full_name: Bryan, Greg L. last_name: Bryan - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Visbal E, Bryan GL, Haiman Z. Self-consistent semianalytic modeling of feedback during primordial star formation and reionization. The Astrophysical Journal. 2020;897(1). doi:10.3847/1538-4357/ab994e apa: Visbal, E., Bryan, G. L., & Haiman, Z. (2020). Self-consistent semianalytic modeling of feedback during primordial star formation and reionization. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/ab994e chicago: Visbal, Eli, Greg L. Bryan, and Zoltán Haiman. “Self-Consistent Semianalytic Modeling of Feedback during Primordial Star Formation and Reionization.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/ab994e. ieee: E. Visbal, G. L. Bryan, and Z. Haiman, “Self-consistent semianalytic modeling of feedback during primordial star formation and reionization,” The Astrophysical Journal, vol. 897, no. 1. American Astronomical Society, 2020. ista: Visbal E, Bryan GL, Haiman Z. 2020. Self-consistent semianalytic modeling of feedback during primordial star formation and reionization. The Astrophysical Journal. 897(1), 95. mla: Visbal, Eli, et al. “Self-Consistent Semianalytic Modeling of Feedback during Primordial Star Formation and Reionization.” The Astrophysical Journal, vol. 897, no. 1, 95, American Astronomical Society, 2020, doi:10.3847/1538-4357/ab994e. short: E. Visbal, G.L. Bryan, Z. Haiman, The Astrophysical Journal 897 (2020). date_created: 2024-09-05T09:58:26Z date_published: 2020-07-07T00:00:00Z date_updated: 2024-09-12T13:28:25Z day: '07' doi: 10.3847/1538-4357/ab994e extern: '1' external_id: arxiv: - '2001.11118' intvolume: ' 897' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2001.11118' month: '07' oa: 1 oa_version: Preprint publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Self-consistent semianalytic modeling of feedback during primordial star formation and reionization type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 897 year: '2020' ... --- _id: '17552' abstract: - lang: eng text: 'We examine the light curves of two quasars, motivated by recent suggestions that a supermassive black hole binary (SMBHB) can exhibit sharp lensing spikes. We model the variability of each light curve as due to a combination of two relativistic effects: the orbital relativistic Doppler boost and gravitational binary self-lensing. In order to model each system we extend previous Doppler plus self-lensing models to include eccentricity. The first quasar is identified in optical data as a binary candidate with a 20-yr period (Ark 120), and shows a prominent spike. For this source, we rule out the lensing hypothesis and disfavor the Doppler-boost hypothesis due to discrepancies in the measured vs. recovered values of the binary mass and optical spectral slope. The second source, which we nickname Spikey, is the rare case of an active galactic nucleus (AGN) identified in Kepler''s high-quality, high-cadence photometric data. For this source, we find a model, consisting of a combination of a Doppler modulation and a narrow symmetric lensing spike, consistent with an eccentric SMBHB with a total mass of approximately 30 million solar masses, rest-frame orbital period T=418 days, eccentricity e=0.5, and seen at an inclination of 8 degrees from edge-on. This interpretation can be tested by monitoring Spikey for periodic behavior and recurring flares in the next few years. In preparation for such monitoring we present the first X-ray observations of this object taken by the Neil Gehrels Swift observatory.' article_processing_charge: No article_type: original author: - first_name: Betty X full_name: Hu, Betty X last_name: Hu - first_name: Daniel J full_name: D’Orazio, Daniel J last_name: D’Orazio - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Krista Lynne full_name: Smith, Krista Lynne last_name: Smith - first_name: Bradford full_name: Snios, Bradford last_name: Snios - first_name: Maria full_name: Charisi, Maria last_name: Charisi - first_name: Rosanne full_name: Di Stefano, Rosanne last_name: Di Stefano citation: ama: 'Hu BX, D’Orazio DJ, Haiman Z, et al. Spikey: self-lensing flares from eccentric SMBH binaries. Monthly Notices of the Royal Astronomical Society. 2020;495(4):4061-4070. doi:10.1093/mnras/staa1312' apa: 'Hu, B. X., D’Orazio, D. J., Haiman, Z., Smith, K. L., Snios, B., Charisi, M., & Di Stefano, R. (2020). Spikey: self-lensing flares from eccentric SMBH binaries. Monthly Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/staa1312' chicago: 'Hu, Betty X, Daniel J D’Orazio, Zoltán Haiman, Krista Lynne Smith, Bradford Snios, Maria Charisi, and Rosanne Di Stefano. “Spikey: Self-Lensing Flares from Eccentric SMBH Binaries.” Monthly Notices of the Royal Astronomical Society. Oxford University Press, 2020. https://doi.org/10.1093/mnras/staa1312.' ieee: 'B. X. Hu et al., “Spikey: self-lensing flares from eccentric SMBH binaries,” Monthly Notices of the Royal Astronomical Society, vol. 495, no. 4. Oxford University Press, pp. 4061–4070, 2020.' ista: 'Hu BX, D’Orazio DJ, Haiman Z, Smith KL, Snios B, Charisi M, Di Stefano R. 2020. Spikey: self-lensing flares from eccentric SMBH binaries. Monthly Notices of the Royal Astronomical Society. 495(4), 4061–4070.' mla: 'Hu, Betty X., et al. “Spikey: Self-Lensing Flares from Eccentric SMBH Binaries.” Monthly Notices of the Royal Astronomical Society, vol. 495, no. 4, Oxford University Press, 2020, pp. 4061–70, doi:10.1093/mnras/staa1312.' short: B.X. Hu, D.J. D’Orazio, Z. Haiman, K.L. Smith, B. Snios, M. Charisi, R. Di Stefano, Monthly Notices of the Royal Astronomical Society 495 (2020) 4061–4070. date_created: 2024-09-05T10:16:03Z date_published: 2020-05-11T00:00:00Z date_updated: 2024-09-18T10:14:15Z day: '11' doi: 10.1093/mnras/staa1312 extern: '1' intvolume: ' 495' issue: '4' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1093/mnras/staa1312 month: '05' oa: 1 oa_version: Published Version page: 4061-4070 publication: Monthly Notices of the Royal Astronomical Society publication_identifier: issn: - 0035-8711 - 1365-2966 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: 'Spikey: self-lensing flares from eccentric SMBH binaries' type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 495 year: '2020' ... --- _id: '17554' abstract: - lang: eng text: The bright quasar PG1302-102 has been identified as a candidate supermassive black hole binary from its near-sinusoidal optical variability. While the significance of its optical periodicity has been debated due to the stochastic variability of quasars, its multiwavelength variability in the ultraviolet (UV) and optical bands is consistent with relativistic Doppler boost caused by the orbital motion in a binary. However, this conclusion was based previously on sparse UV data that were not taken simultaneously with the optical data. Here, we report simultaneous follow-up observations of PG1302-102 with the Ultraviolet Optical Telescope on the Neil Gehrels Swift Observatory in six optical + UV bands. The additional nine Swift observations produce light curves roughly consistent with the trend under the Doppler boost hypothesis, which predicts that UV variability should track the optical, but with a ∼2.2 times higher amplitude. We perform a statistical analysis to quantitatively test this hypothesis. We find that the data are consistent with the Doppler boost hypothesis when we compare the the amplitudes in optical B-band and UV light curves. However, the ratio of UV to V-band variability is larger than expected and is consistent with the Doppler model, only if either the UV/optical spectral slopes vary, the stochastic variability makes a large contribution in the UV, or the sparse new optical data underestimate the true optical variability. We have evidence for the latter from comparison with the optical light curve from All-Sky Automated Survey for Supernovae. Additionally, the simultaneous analysis of all four bands strongly disfavours the Doppler boost model whenever Swift V band is involved. Additional, simultaneous optical + UV observations tracing out another cycle of the 5.2-yr proposed periodicity should lead to a definitive conclusion. article_processing_charge: No article_type: original author: - first_name: Chengcheng full_name: Xin, Chengcheng last_name: Xin - first_name: Maria full_name: Charisi, Maria last_name: Charisi - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: David full_name: Schiminovich, David last_name: Schiminovich - first_name: Matthew J full_name: Graham, Matthew J last_name: Graham - first_name: Daniel full_name: Stern, Daniel last_name: Stern - first_name: Daniel J full_name: D’Orazio, Daniel J last_name: D’Orazio citation: ama: Xin C, Charisi M, Haiman Z, et al. Testing the relativistic Doppler boost hypothesis for the binary candidate quasar PG1302-102 with multiband Swift data. Monthly Notices of the Royal Astronomical Society. 2020;496(2):1683-1696. doi:10.1093/mnras/staa1643 apa: Xin, C., Charisi, M., Haiman, Z., Schiminovich, D., Graham, M. J., Stern, D., & D’Orazio, D. J. (2020). Testing the relativistic Doppler boost hypothesis for the binary candidate quasar PG1302-102 with multiband Swift data. Monthly Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/staa1643 chicago: Xin, Chengcheng, Maria Charisi, Zoltán Haiman, David Schiminovich, Matthew J Graham, Daniel Stern, and Daniel J D’Orazio. “Testing the Relativistic Doppler Boost Hypothesis for the Binary Candidate Quasar PG1302-102 with Multiband Swift Data.” Monthly Notices of the Royal Astronomical Society. Oxford University Press, 2020. https://doi.org/10.1093/mnras/staa1643. ieee: C. Xin et al., “Testing the relativistic Doppler boost hypothesis for the binary candidate quasar PG1302-102 with multiband Swift data,” Monthly Notices of the Royal Astronomical Society, vol. 496, no. 2. Oxford University Press, pp. 1683–1696, 2020. ista: Xin C, Charisi M, Haiman Z, Schiminovich D, Graham MJ, Stern D, D’Orazio DJ. 2020. Testing the relativistic Doppler boost hypothesis for the binary candidate quasar PG1302-102 with multiband Swift data. Monthly Notices of the Royal Astronomical Society. 496(2), 1683–1696. mla: Xin, Chengcheng, et al. “Testing the Relativistic Doppler Boost Hypothesis for the Binary Candidate Quasar PG1302-102 with Multiband Swift Data.” Monthly Notices of the Royal Astronomical Society, vol. 496, no. 2, Oxford University Press, 2020, pp. 1683–96, doi:10.1093/mnras/staa1643. short: C. Xin, M. Charisi, Z. Haiman, D. Schiminovich, M.J. Graham, D. Stern, D.J. D’Orazio, Monthly Notices of the Royal Astronomical Society 496 (2020) 1683–1696. date_created: 2024-09-05T10:22:00Z date_published: 2020-06-10T00:00:00Z date_updated: 2024-09-18T10:23:02Z day: '10' doi: 10.1093/mnras/staa1643 extern: '1' intvolume: ' 496' issue: '2' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1093/mnras/staa1643 month: '06' oa: 1 oa_version: Published Version page: 1683-1696 publication: Monthly Notices of the Royal Astronomical Society publication_identifier: issn: - 0035-8711 - 1365-2966 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: Testing the relativistic Doppler boost hypothesis for the binary candidate quasar PG1302-102 with multiband Swift data type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 496 year: '2020' ... --- _id: '17564' abstract: - lang: eng text: 'The existence of ≈10^9 Msun supermassive black holes (SMBHs) within the first billion year of the universe has stimulated numerous ideas for the prompt formation and rapid growth of BHs in the early universe. Here we review ways in which the seeds of massive BHs may have first assembled, how they may have subsequently grown as massive as ≈10^9 Msun, and how multi-messenger observations could distinguish between different SMBH assembly scenarios. We conclude the following: (1) The ultra-rare ≈10^9 Msun SMBHs represent only the tip of the iceberg. Early BHs likely fill a continuum from stellar-mass (approx. 10 Msun) to the super-massive (≈10^9 Msun) regime, reflecting a range of initial masses and growth histories. (2) Stellar-mass BHs were likely left behind by the first generation of stars at redshifts as high as z=30, but their initial growth was typically stunted due to the shallow potential wells of their host galaxies. (3) Conditions in some larger, metal-poor galaxies soon became conducive to the rapid formation and growth of massive `seed'' holes, via gas accretion and by mergers in dense stellar clusters. (4) BH masses depend on the environment (such as the number and properties of nearby radiation sources and the local baryonic streaming velocity), and on the metal enrichment and assembly history of the host galaxy. (5) Distinguishing between assembly mechanisms will be difficult, but a combination of observations by LISA (probing massive BH growth via mergers) and by deep multi-wavelength electromagnetic observations (probing growth via gas accretion) is particularly promising.' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Kohei full_name: Inayoshi, Kohei last_name: Inayoshi - first_name: Eli full_name: Visbal, Eli last_name: Visbal - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Inayoshi K, Visbal E, Haiman Z. The Assembly of the First Massive Black Holes. Annual Review of Astronomy and Astrophysics. 2020;58(1):27-97. doi:10.1146/annurev-astro-120419-014455 apa: Inayoshi, K., Visbal, E., & Haiman, Z. (2020). The Assembly of the First Massive Black Holes. Annual Review of Astronomy and Astrophysics. Annual Reviews. https://doi.org/10.1146/annurev-astro-120419-014455 chicago: Inayoshi, Kohei, Eli Visbal, and Zoltán Haiman. “The Assembly of the First Massive Black Holes.” Annual Review of Astronomy and Astrophysics. Annual Reviews, 2020. https://doi.org/10.1146/annurev-astro-120419-014455. ieee: K. Inayoshi, E. Visbal, and Z. Haiman, “The Assembly of the First Massive Black Holes,” Annual Review of Astronomy and Astrophysics, vol. 58, no. 1. Annual Reviews, pp. 27–97, 2020. ista: Inayoshi K, Visbal E, Haiman Z. 2020. The Assembly of the First Massive Black Holes. Annual Review of Astronomy and Astrophysics. 58(1), 27–97. mla: Inayoshi, Kohei, et al. “The Assembly of the First Massive Black Holes.” Annual Review of Astronomy and Astrophysics, vol. 58, no. 1, Annual Reviews, 2020, pp. 27–97, doi:10.1146/annurev-astro-120419-014455. short: K. Inayoshi, E. Visbal, Z. Haiman, Annual Review of Astronomy and Astrophysics 58 (2020) 27–97. date_created: 2024-09-05T12:04:49Z date_published: 2020-03-30T00:00:00Z date_updated: 2024-09-18T13:06:37Z day: '30' doi: 10.1146/annurev-astro-120419-014455 extern: '1' external_id: arxiv: - '1911.05791' intvolume: ' 58' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.1911.05791' month: '03' oa: 1 oa_version: Preprint page: 27-97 publication: Annual Review of Astronomy and Astrophysics publication_identifier: issn: - 0066-4146 - 1545-4282 publication_status: published publisher: Annual Reviews quality_controlled: '1' scopus_import: '1' status: public title: The Assembly of the First Massive Black Holes type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 58 year: '2020' ... --- _id: '17566' abstract: - lang: eng text: The formation of supermassive stars has generally been studied under the assumption of rapid accretion of pristine metal-free gas. Recently it was found, however, that gas enriched to metallicities up to Z∼10−3 Z⊙ can also facilitate supermassive star formation, as long as the total mass infall rate onto the protostar remains sufficiently high. We extend the analysis further by examining how the abundance of supermassive star candidate haloes would be affected if all haloes with super-critical infall rates, regardless of metallicity were included. We investigate this scenario by identifying all atomic cooling haloes in the Renaissance simulations with central mass infall rates exceeding a fixed threshold. We find that among these haloes with central mass infall rates above 0.1 M⊙ yr−1 approximately two-thirds of these haloes have metallicities of Z>10−3 Z⊙. If metal mixing within these haloes is inefficient early in their assembly and pockets of metal-poor gas can remain then the number of haloes hosting supermassive stars can be increased by at least a factor of four. Additionally the centres of these high infall-rate haloes provide ideal environments in which to grow pre-existing black holes. Further research into the (supermassive) star formation dynamics of rapidly collapsing haloes, with inhomogeneous metal distributions, is required to gain more insight into both supermassive star formation in early galaxies as well as early black hole growth. article_processing_charge: No article_type: original author: - first_name: John A. full_name: Regan, John A. last_name: Regan - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: John H. full_name: Wise, John H. last_name: Wise - first_name: Brian W. full_name: O'Shea, Brian W. last_name: O'Shea - first_name: Michael L. full_name: Norman, Michael L. last_name: Norman citation: ama: Regan JA, Haiman Z, Wise JH, O’Shea BW, Norman ML. Massive star formation in metal-enriched haloes at high redshift. The Open Journal of Astrophysics. 2020;3(1). doi:10.21105/astro.2006.14625 apa: Regan, J. A., Haiman, Z., Wise, J. H., O’Shea, B. W., & Norman, M. L. (2020). Massive star formation in metal-enriched haloes at high redshift. The Open Journal of Astrophysics. Maynooth University. https://doi.org/10.21105/astro.2006.14625 chicago: Regan, John A., Zoltán Haiman, John H. Wise, Brian W. O’Shea, and Michael L. Norman. “Massive Star Formation in Metal-Enriched Haloes at High Redshift.” The Open Journal of Astrophysics. Maynooth University, 2020. https://doi.org/10.21105/astro.2006.14625. ieee: J. A. Regan, Z. Haiman, J. H. Wise, B. W. O’Shea, and M. L. Norman, “Massive star formation in metal-enriched haloes at high redshift,” The Open Journal of Astrophysics, vol. 3, no. 1. Maynooth University, 2020. ista: Regan JA, Haiman Z, Wise JH, O’Shea BW, Norman ML. 2020. Massive star formation in metal-enriched haloes at high redshift. The Open Journal of Astrophysics. 3(1). mla: Regan, John A., et al. “Massive Star Formation in Metal-Enriched Haloes at High Redshift.” The Open Journal of Astrophysics, vol. 3, no. 1, Maynooth University, 2020, doi:10.21105/astro.2006.14625. short: J.A. Regan, Z. Haiman, J.H. Wise, B.W. O’Shea, M.L. Norman, The Open Journal of Astrophysics 3 (2020). date_created: 2024-09-05T12:07:42Z date_published: 2020-08-24T00:00:00Z date_updated: 2024-09-18T13:17:51Z day: '24' doi: 10.21105/astro.2006.14625 extern: '1' intvolume: ' 3' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.21105/astro.2006.14625 month: '08' oa: 1 oa_version: Published Version publication: The Open Journal of Astrophysics publication_identifier: issn: - 2565-6120 publication_status: published publisher: Maynooth University quality_controlled: '1' scopus_import: '1' status: public title: Massive star formation in metal-enriched haloes at high redshift type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 3 year: '2020' ... --- _id: '17579' abstract: - lang: eng text: Approximately 200 supermassive black holes (SMBHs) have been discovered within the first ∼gigayear after the Big Bang. One pathway for the formation of SMBHs is through the collapse of supermassive stars (SMSs). A possible obstacle to this scenario is that the collapsing gas fragments and forms a cluster of main-sequence stars. Here, we raise the possibility that stellar collisions may be sufficiently frequent and energetic to inhibit the contraction of the massive protostar, avoiding strong UV radiation driven outflows, and allowing it to continue growing into an SMS. We investigate this scenario with semianalytic models incorporating star formation; gas accretion; dynamical friction from stars and gas; stellar collisions; and gas ejection. We find that when the collapsing gas fragments at a density of ≲3 × 1010 cm−3, the central protostar contracts due to infrequent stellar mergers, and in turn photoevaporates the remaining collapsing gas, resulting in the formation of a ≲104 M⊙ object. On the other hand, when the collapsing gas fragments at higher densities (expected for a metal-poor cloud with Z ≲ 10−5 Z⊙ with suppressed H2 abundance) the central protostar avoids contraction and keeps growing via frequent stellar mergers, reaching masses as high as ∼105–106 M⊙. We conclude that frequent stellar mergers represent a possible pathway to form massive BHs in the early universe. article_number: '36' article_processing_charge: No article_type: original author: - first_name: Hiromichi full_name: Tagawa, Hiromichi last_name: Tagawa - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Bence full_name: Kocsis, Bence last_name: Kocsis citation: ama: Tagawa H, Haiman Z, Kocsis B. Making a supermassive star by stellar bombardment. The Astrophysical Journal. 2020;892(1). doi:10.3847/1538-4357/ab7922 apa: Tagawa, H., Haiman, Z., & Kocsis, B. (2020). Making a supermassive star by stellar bombardment. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/ab7922 chicago: Tagawa, Hiromichi, Zoltán Haiman, and Bence Kocsis. “Making a Supermassive Star by Stellar Bombardment.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/ab7922. ieee: H. Tagawa, Z. Haiman, and B. Kocsis, “Making a supermassive star by stellar bombardment,” The Astrophysical Journal, vol. 892, no. 1. American Astronomical Society, 2020. ista: Tagawa H, Haiman Z, Kocsis B. 2020. Making a supermassive star by stellar bombardment. The Astrophysical Journal. 892(1), 36. mla: Tagawa, Hiromichi, et al. “Making a Supermassive Star by Stellar Bombardment.” The Astrophysical Journal, vol. 892, no. 1, 36, American Astronomical Society, 2020, doi:10.3847/1538-4357/ab7922. short: H. Tagawa, Z. Haiman, B. Kocsis, The Astrophysical Journal 892 (2020). date_created: 2024-09-05T12:22:41Z date_published: 2020-03-24T00:00:00Z date_updated: 2024-09-19T11:21:17Z day: '24' doi: 10.3847/1538-4357/ab7922 extern: '1' intvolume: ' 892' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3847/1538-4357/ab7922 month: '03' oa: 1 oa_version: Published Version publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Making a supermassive star by stellar bombardment type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 892 year: '2020' ... --- _id: '17581' abstract: - lang: eng text: We present analysis of Chandra X-ray observations of seven quasars that were identified as candidate subparsec binary supermassive black hole (SMBH) systems in the Catalina Real-Time Transient Survey based on the apparent periodicity in their optical light curves. Simulations predict that close-separation accreting SMBH binaries will have different X-ray spectra than single accreting SMBHs, including harder or softer X-ray spectra, ripple-like profiles in the Fe K-α line, and distinct peaks in the spectrum due to the separation of the accretion disk into a circumbinary disk and mini disks around each SMBH. We obtained Chandra observations to test these models and assess whether these quasars could contain binary SMBHs. We instead find that the quasar spectra are all well fit by simple absorbed power-law models, with the rest-frame 2–10 keV photon indices, Γ, and the X-ray-to-optical power slopes, αOX, indistinguishable from those of the larger quasar population. This may indicate that these seven quasars are not truly subparsec binary SMBH systems, or it may simply reflect that our sample size was too small to robustly detect any differences. Alternatively, the X-ray spectral changes might only be evident at energies higher than probed by Chandra. Given the available models and current data, no firm conclusions are drawn. These observations will help motivate and direct further work on theoretical models of binary SMBH systems, such as modeling systems with thinner accretion disks and larger binary separations. article_number: '148' article_processing_charge: No article_type: original author: - first_name: M. Lynne full_name: Saade, M. Lynne last_name: Saade - first_name: Daniel full_name: Stern, Daniel last_name: Stern - first_name: Murray full_name: Brightman, Murray last_name: Brightman - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: S. G. full_name: Djorgovski, S. G. last_name: Djorgovski - first_name: Daniel full_name: D’Orazio, Daniel last_name: D’Orazio - first_name: K. E. S. full_name: Ford, K. E. S. last_name: Ford - first_name: Matthew J. full_name: Graham, Matthew J. last_name: Graham - first_name: Hyunsung D. full_name: Jun, Hyunsung D. last_name: Jun - first_name: Ralph P. full_name: Kraft, Ralph P. last_name: Kraft - first_name: Barry full_name: McKernan, Barry last_name: McKernan - first_name: Alexei full_name: Vikhlinin, Alexei last_name: Vikhlinin - first_name: Dominic J. full_name: Walton, Dominic J. last_name: Walton citation: ama: Saade ML, Stern D, Brightman M, et al. Chandra observations of candidate subparsec binary supermassive black holes. The Astrophysical Journal. 2020;900(2). doi:10.3847/1538-4357/abad31 apa: Saade, M. L., Stern, D., Brightman, M., Haiman, Z., Djorgovski, S. G., D’Orazio, D., … Walton, D. J. (2020). Chandra observations of candidate subparsec binary supermassive black holes. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/abad31 chicago: Saade, M. Lynne, Daniel Stern, Murray Brightman, Zoltán Haiman, S. G. Djorgovski, Daniel D’Orazio, K. E. S. Ford, et al. “Chandra Observations of Candidate Subparsec Binary Supermassive Black Holes.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/abad31. ieee: M. L. Saade et al., “Chandra observations of candidate subparsec binary supermassive black holes,” The Astrophysical Journal, vol. 900, no. 2. American Astronomical Society, 2020. ista: Saade ML, Stern D, Brightman M, Haiman Z, Djorgovski SG, D’Orazio D, Ford KES, Graham MJ, Jun HD, Kraft RP, McKernan B, Vikhlinin A, Walton DJ. 2020. Chandra observations of candidate subparsec binary supermassive black holes. The Astrophysical Journal. 900(2), 148. mla: Saade, M. Lynne, et al. “Chandra Observations of Candidate Subparsec Binary Supermassive Black Holes.” The Astrophysical Journal, vol. 900, no. 2, 148, American Astronomical Society, 2020, doi:10.3847/1538-4357/abad31. short: M.L. Saade, D. Stern, M. Brightman, Z. Haiman, S.G. Djorgovski, D. D’Orazio, K.E.S. Ford, M.J. Graham, H.D. Jun, R.P. Kraft, B. McKernan, A. Vikhlinin, D.J. Walton, The Astrophysical Journal 900 (2020). date_created: 2024-09-05T12:25:06Z date_published: 2020-09-11T00:00:00Z date_updated: 2024-09-19T11:29:46Z day: '11' doi: 10.3847/1538-4357/abad31 extern: '1' intvolume: ' 900' issue: '2' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3847/1538-4357/abad31 month: '09' oa: 1 oa_version: Published Version publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Chandra observations of candidate subparsec binary supermassive black holes type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 900 year: '2020' ... --- _id: '17587' abstract: - lang: eng text: 'The astrophysical origin of gravitational wave (GW) events discovered by LIGO/VIRGO remains an outstanding puzzle. In active galactic nuclei (AGNs), compact-object binaries form, evolve, and interact with a dense star cluster and a gas disk. An important question is whether and how binaries merge in these environments. To address this question, we have performed one-dimensional N-body simulations combined with a semianalytical model that includes the formation, disruption, and evolution of binaries self-consistently. We point out that binaries can form in single–single interactions through the dissipation of kinetic energy in a gaseous medium. This "gas-capture" binary formation channel contributes up to 97% of gas-driven mergers and leads to a high merger rate in AGN disks even without preexisting binaries. We find the merger rate to be in the range of ∼0.02–60 Gpc−3 yr−1. The results are insensitive to the assumptions on the gaseous hardening processes: we find that once they are formed, binaries merge efficiently via binary–single interactions even if these gaseous processes are ignored. We find that the average number of mergers per black hole (BH) is 0.4, and the probability for repeated mergers in 30 Myr is ∼0.21–0.45. High BH masses due to repeated mergers, high eccentricities, and a significant Doppler drift of GWs are promising signatures that distinguish this merger channel from others. Furthermore, we find that gas-capture binaries reproduce the distribution of low-mass X-ray binaries in the Galactic center, including an outer cutoff at ∼1 pc due to the competition between migration and hardening by gas torques.' article_number: '25' article_processing_charge: No article_type: original author: - first_name: Hiromichi full_name: Tagawa, Hiromichi last_name: Tagawa - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Bence full_name: Kocsis, Bence last_name: Kocsis citation: ama: Tagawa H, Haiman Z, Kocsis B. Formation and evolution of compact-object binaries in AGN disks. The Astrophysical Journal. 2020;898(1). doi:10.3847/1538-4357/ab9b8c apa: Tagawa, H., Haiman, Z., & Kocsis, B. (2020). Formation and evolution of compact-object binaries in AGN disks. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/ab9b8c chicago: Tagawa, Hiromichi, Zoltán Haiman, and Bence Kocsis. “Formation and Evolution of Compact-Object Binaries in AGN Disks.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/ab9b8c. ieee: H. Tagawa, Z. Haiman, and B. Kocsis, “Formation and evolution of compact-object binaries in AGN disks,” The Astrophysical Journal, vol. 898, no. 1. American Astronomical Society, 2020. ista: Tagawa H, Haiman Z, Kocsis B. 2020. Formation and evolution of compact-object binaries in AGN disks. The Astrophysical Journal. 898(1), 25. mla: Tagawa, Hiromichi, et al. “Formation and Evolution of Compact-Object Binaries in AGN Disks.” The Astrophysical Journal, vol. 898, no. 1, 25, American Astronomical Society, 2020, doi:10.3847/1538-4357/ab9b8c. short: H. Tagawa, Z. Haiman, B. Kocsis, The Astrophysical Journal 898 (2020). date_created: 2024-09-05T12:33:11Z date_published: 2020-07-20T00:00:00Z date_updated: 2024-09-19T11:59:23Z day: '20' doi: 10.3847/1538-4357/ab9b8c extern: '1' intvolume: ' 898' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3847/1538-4357/ab9b8c month: '07' oa: 1 oa_version: Published Version publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Formation and evolution of compact-object binaries in AGN disks type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 898 year: '2020' ... --- _id: '17591' abstract: - lang: eng text: "The rotational kinematic Sunyaev-Zeldovich (rkSZ) signal, imprinted on the cosmic microwave background (CMB) by the gaseous halos (spinning “atmospheres”) of foreground galaxies, would be a novel probe of galaxy formation. Although the signal is too weak to detect in individual galaxies, we analyze the feasibility of its statistical detection via stacking CMB data on many galaxies for which the spin orientation can be estimated spectroscopically. We use an “optimistic” model, in which fully ionized atmospheres contain the cosmic baryon fraction and spin at the halo’s circular velocity \U0001D463circ, and a more realistic model, based on hydrodynamical simulations, with multiphase atmospheres spinning at a fraction of \U0001D463circ. We incorporate realistic noise estimates into our analysis. Using low-redshift galaxy properties from the MaNGA spectroscopic survey (with median halo mass of 6.6×1011  \U0001D440⊙), and CMB data quality from Planck, we find that a 3⁢\U0001D70E detection would require a few×104 galaxies, even in the optimistic model. This is too high for current surveys, but upcoming higher-angular resolution CMB experiments will significantly reduce the requirements: stacking CMB data on galaxy spins in a ∼10 deg2 can rule out the optimistic models, and ≈350  deg2 will suffice for a 3⁢\U0001D70E detection with ACT. As a proof-of-concept, we stacked Planck data on the position of ≈2,000 MaNGA galaxies, aligned with the galaxies’ projected spin, and scaled to their halos’ angular size. We rule out average temperature dipoles larger than ≈1.9  \U0001D707⁢K around field spiral galaxies." article_number: '083016' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: José Manuel Zorrilla full_name: Matilla, José Manuel Zorrilla last_name: Matilla - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Matilla JMZ, Haiman Z. Probing gaseous galactic halos through the rotational kinematic Sunyaev-Zeldovich effect. Physical Review D. 2020;101(8). doi:10.1103/physrevd.101.083016 apa: Matilla, J. M. Z., & Haiman, Z. (2020). Probing gaseous galactic halos through the rotational kinematic Sunyaev-Zeldovich effect. Physical Review D. American Physical Society. https://doi.org/10.1103/physrevd.101.083016 chicago: Matilla, José Manuel Zorrilla, and Zoltán Haiman. “Probing Gaseous Galactic Halos through the Rotational Kinematic Sunyaev-Zeldovich Effect.” Physical Review D. American Physical Society, 2020. https://doi.org/10.1103/physrevd.101.083016. ieee: J. M. Z. Matilla and Z. Haiman, “Probing gaseous galactic halos through the rotational kinematic Sunyaev-Zeldovich effect,” Physical Review D, vol. 101, no. 8. American Physical Society, 2020. ista: Matilla JMZ, Haiman Z. 2020. Probing gaseous galactic halos through the rotational kinematic Sunyaev-Zeldovich effect. Physical Review D. 101(8), 083016. mla: Matilla, José Manuel Zorrilla, and Zoltán Haiman. “Probing Gaseous Galactic Halos through the Rotational Kinematic Sunyaev-Zeldovich Effect.” Physical Review D, vol. 101, no. 8, 083016, American Physical Society, 2020, doi:10.1103/physrevd.101.083016. short: J.M.Z. Matilla, Z. Haiman, Physical Review D 101 (2020). date_created: 2024-09-05T12:37:26Z date_published: 2020-04-10T00:00:00Z date_updated: 2024-09-19T12:26:58Z day: '10' doi: 10.1103/physrevd.101.083016 extern: '1' external_id: arxiv: - '1909.04690' intvolume: ' 101' issue: '8' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.1909.04690' month: '04' oa: 1 oa_version: Preprint publication: Physical Review D publication_identifier: issn: - 2470-0010 - 2470-0029 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Probing gaseous galactic halos through the rotational kinematic Sunyaev-Zeldovich effect type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 101 year: '2020' ... --- _id: '17595' abstract: - lang: eng text: We study the thermal evolution of UV-irradiated atomic cooling haloes using high-resolution three-dimensional hydrodynamic simulations. We consider the effect of H− photodetachment by Lyα cooling radiation trapped in the optically-thick cores of three such haloes, a process that has not been included in previous simulations. Because H− is a precursor of molecular hydrogen, its destruction can diminish the H2 abundance and cooling. We find that the critical UV flux for suppressing H2-cooling is decreased by ∼15–50 per cent in our fiducial models. Previous one-zone modelling found a larger effect, with Jcrit reduced by a factor of a few; we show that adopting a constant halo mass to determine the trapped Lyα energy density, as is done in the one-zone models, yields a larger reduction in Jcrit, consistent with their findings. Our results nevertheless suggest that Lyα radiation may have an important effect on the thermal evolution of UV-irradiated haloes, and therefore on the potential for massive black hole formation. article_processing_charge: No article_type: original author: - first_name: Jemma full_name: Wolcott-Green, Jemma last_name: Wolcott-Green - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Greg L full_name: Bryan, Greg L last_name: Bryan citation: ama: Wolcott-Green J, Haiman Z, Bryan GL. Suppression of H2 cooling in protogalaxies aided by trapped Lyα cooling radiation. Monthly Notices of the Royal Astronomical Society. 2020;500(1):138-144. doi:10.1093/mnras/staa3057 apa: Wolcott-Green, J., Haiman, Z., & Bryan, G. L. (2020). Suppression of H2 cooling in protogalaxies aided by trapped Lyα cooling radiation. Monthly Notices of the Royal Astronomical Society. Oxford University Press. https://doi.org/10.1093/mnras/staa3057 chicago: Wolcott-Green, Jemma, Zoltán Haiman, and Greg L Bryan. “Suppression of H2 Cooling in Protogalaxies Aided by Trapped Lyα Cooling Radiation.” Monthly Notices of the Royal Astronomical Society. Oxford University Press, 2020. https://doi.org/10.1093/mnras/staa3057. ieee: J. Wolcott-Green, Z. Haiman, and G. L. Bryan, “Suppression of H2 cooling in protogalaxies aided by trapped Lyα cooling radiation,” Monthly Notices of the Royal Astronomical Society, vol. 500, no. 1. Oxford University Press, pp. 138–144, 2020. ista: Wolcott-Green J, Haiman Z, Bryan GL. 2020. Suppression of H2 cooling in protogalaxies aided by trapped Lyα cooling radiation. Monthly Notices of the Royal Astronomical Society. 500(1), 138–144. mla: Wolcott-Green, Jemma, et al. “Suppression of H2 Cooling in Protogalaxies Aided by Trapped Lyα Cooling Radiation.” Monthly Notices of the Royal Astronomical Society, vol. 500, no. 1, Oxford University Press, 2020, pp. 138–44, doi:10.1093/mnras/staa3057. short: J. Wolcott-Green, Z. Haiman, G.L. Bryan, Monthly Notices of the Royal Astronomical Society 500 (2020) 138–144. date_created: 2024-09-05T12:42:37Z date_published: 2020-10-09T00:00:00Z date_updated: 2024-09-23T12:42:07Z day: '09' doi: 10.1093/mnras/staa3057 extern: '1' intvolume: ' 500' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1093/mnras/staa3057 month: '10' oa: 1 oa_version: Published Version page: 138-144 publication: Monthly Notices of the Royal Astronomical Society publication_identifier: issn: - 0035-8711 - 1365-2966 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: Suppression of H2 cooling in protogalaxies aided by trapped Lyα cooling radiation type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 500 year: '2020' ... --- _id: '17596' abstract: - lang: eng text: Binary black hole mergers encode information about their environment and the astrophysical processes that led to their formation. Measuring the redshift dependence of their merger rate will help probe the formation and evolution of galaxies and the evolution of the star formation rate. Here we compute the cosmic evolution of the merger rate for stellar-mass binaries in the disks of active galactic nuclei (AGNs). We focus on recent evolution out to redshift z = 2, covering the accessible range of current Earth-based gravitational-wave observatories. On this scale, the AGN population density is the main contributor to redshift dependence. We find that the AGN-assisted merger rate varies by less than a factor of two in the range 0 < z ≤ 2, comparable to the expected level of evolution for globular clusters, but much smaller than the order-of-magnitude evolution for field binaries. article_number: '138' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Y. full_name: Yang, Y. last_name: Yang - first_name: I. full_name: Bartos, I. last_name: Bartos - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: B. full_name: Kocsis, B. last_name: Kocsis - first_name: S. full_name: Márka, S. last_name: Márka - first_name: H. full_name: Tagawa, H. last_name: Tagawa citation: ama: Yang Y, Bartos I, Haiman Z, Kocsis B, Márka S, Tagawa H. Cosmic evolution of stellar-mass black hole merger rate in active galactic nuclei. The Astrophysical Journal. 2020;896(2). doi:10.3847/1538-4357/ab91b4 apa: Yang, Y., Bartos, I., Haiman, Z., Kocsis, B., Márka, S., & Tagawa, H. (2020). Cosmic evolution of stellar-mass black hole merger rate in active galactic nuclei. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/ab91b4 chicago: Yang, Y., I. Bartos, Zoltán Haiman, B. Kocsis, S. Márka, and H. Tagawa. “Cosmic Evolution of Stellar-Mass Black Hole Merger Rate in Active Galactic Nuclei.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/ab91b4. ieee: Y. Yang, I. Bartos, Z. Haiman, B. Kocsis, S. Márka, and H. Tagawa, “Cosmic evolution of stellar-mass black hole merger rate in active galactic nuclei,” The Astrophysical Journal, vol. 896, no. 2. American Astronomical Society, 2020. ista: Yang Y, Bartos I, Haiman Z, Kocsis B, Márka S, Tagawa H. 2020. Cosmic evolution of stellar-mass black hole merger rate in active galactic nuclei. The Astrophysical Journal. 896(2), 138. mla: Yang, Y., et al. “Cosmic Evolution of Stellar-Mass Black Hole Merger Rate in Active Galactic Nuclei.” The Astrophysical Journal, vol. 896, no. 2, 138, American Astronomical Society, 2020, doi:10.3847/1538-4357/ab91b4. short: Y. Yang, I. Bartos, Z. Haiman, B. Kocsis, S. Márka, H. Tagawa, The Astrophysical Journal 896 (2020). date_created: 2024-09-05T12:43:28Z date_published: 2020-06-22T00:00:00Z date_updated: 2024-09-23T12:59:52Z day: '22' doi: 10.3847/1538-4357/ab91b4 extern: '1' external_id: arxiv: - '2003.08564' intvolume: ' 896' issue: '2' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2003.08564' month: '06' oa: 1 oa_version: Preprint publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Cosmic evolution of stellar-mass black hole merger rate in active galactic nuclei type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 896 year: '2020' ... --- _id: '17597' abstract: - lang: eng text: Deep Neural Networks (DNNs) are powerful algorithms that have been proven capable of extracting non-Gaussian information from weak lensing (WL) data sets. Understanding which features in the data determine the output of these nested, non-linear algorithms is an important but challenging task. We analyze a DNN that has been found in previous work to accurately recover cosmological parameters in simulated maps of the WL convergence (κ). We derive constraints on the cosmological parameter pair (Ωm,σ8) from a combination of three commonly used WL statistics (power spectrum, lensing peaks, and Minkowski functionals), using ray-traced simulated κ maps. We show that the network can improve the inferred parameter constraints relative to this combination by 20% even in the presence of realistic levels of shape noise. We apply a series of well established saliency methods to interpret the DNN and find that the most relevant pixels are those with extreme κ values. For noiseless maps, regions with negative κ account for 86−69% of the attribution of the DNN output, defined as the square of the saliency in input space. In the presence of shape nose, the attribution concentrates in high convergence regions, with 36−68% of the attribution in regions with κ>3σκ. article_number: '123506' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: José Manuel Zorrilla full_name: Matilla, José Manuel Zorrilla last_name: Matilla - first_name: Manasi full_name: Sharma, Manasi last_name: Sharma - first_name: Daniel full_name: Hsu, Daniel last_name: Hsu - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Matilla JMZ, Sharma M, Hsu D, Haiman Z. Interpreting deep learning models for weak lensing. Physical Review D. 2020;102(12). doi:10.1103/physrevd.102.123506 apa: Matilla, J. M. Z., Sharma, M., Hsu, D., & Haiman, Z. (2020). Interpreting deep learning models for weak lensing. Physical Review D. American Physical Society. https://doi.org/10.1103/physrevd.102.123506 chicago: Matilla, José Manuel Zorrilla, Manasi Sharma, Daniel Hsu, and Zoltán Haiman. “Interpreting Deep Learning Models for Weak Lensing.” Physical Review D. American Physical Society, 2020. https://doi.org/10.1103/physrevd.102.123506. ieee: J. M. Z. Matilla, M. Sharma, D. Hsu, and Z. Haiman, “Interpreting deep learning models for weak lensing,” Physical Review D, vol. 102, no. 12. American Physical Society, 2020. ista: Matilla JMZ, Sharma M, Hsu D, Haiman Z. 2020. Interpreting deep learning models for weak lensing. Physical Review D. 102(12), 123506. mla: Matilla, José Manuel Zorrilla, et al. “Interpreting Deep Learning Models for Weak Lensing.” Physical Review D, vol. 102, no. 12, 123506, American Physical Society, 2020, doi:10.1103/physrevd.102.123506. short: J.M.Z. Matilla, M. Sharma, D. Hsu, Z. Haiman, Physical Review D 102 (2020). date_created: 2024-09-05T12:44:45Z date_published: 2020-07-09T00:00:00Z date_updated: 2024-09-23T13:04:36Z day: '09' doi: 10.1103/physrevd.102.123506 extern: '1' external_id: arxiv: - '2007.06529' intvolume: ' 102' issue: '12' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2007.06529' month: '07' oa: 1 oa_version: Preprint publication: Physical Review D publication_identifier: issn: - 2470-0010 - 2470-0029 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Interpreting deep learning models for weak lensing type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 102 year: '2020' ... --- _id: '17600' abstract: - lang: eng text: The quest for binary and dual supermassive black holes (SMBHs) at the dawn of the multi-messenger era is compelling. Detecting dual active galactic nuclei (AGN) – active SMBHs at projected separations larger than several parsecs – and binary AGN – probing the scale where SMBHs are bound in a Keplerian binary – is an observational challenge. The study of AGN pairs (either dual or binary) also represents an overarching theoretical problem in cosmology and astrophysics. The AGN triggering calls for detailed knowledge of the hydrodynamical conditions of gas in the imminent surroundings of the SMBHs and, at the same time, their duality calls for detailed knowledge on how galaxies assemble through major and minor mergers and grow fed by matter along the filaments of the cosmic web. This review describes the techniques used across the electromagnetic spectrum to detect dual and binary AGN candidates and proposes new avenues for their search. The current observational status is compared with the state-of-the-art numerical simulations and models for formation of dual and binary AGN. Binary SMBHs are among the loudest sources of gravitational waves (GWs) in the Universe. The search for a background of GWs at nHz frequencies from inspiralling SMBHs at low redshifts, and the direct detection of signals from their coalescence by the Laser Interferometer Space Antenna in the next decade, make this a theme of major interest for multi-messenger astrophysics. This review discusses the future facilities and observational strategies that are likely to significantly advance this fascinating field. article_number: '101525' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Alessandra full_name: De Rosa, Alessandra last_name: De Rosa - first_name: Cristian full_name: Vignali, Cristian last_name: Vignali - first_name: Tamara full_name: Bogdanović, Tamara last_name: Bogdanović - first_name: Pedro R. full_name: Capelo, Pedro R. last_name: Capelo - first_name: Maria full_name: Charisi, Maria last_name: Charisi - first_name: Massimo full_name: Dotti, Massimo last_name: Dotti - first_name: Bernd full_name: Husemann, Bernd last_name: Husemann - first_name: Elisabeta full_name: Lusso, Elisabeta last_name: Lusso - first_name: Lucio full_name: Mayer, Lucio last_name: Mayer - first_name: Zsolt full_name: Paragi, Zsolt last_name: Paragi - first_name: Jessie full_name: Runnoe, Jessie last_name: Runnoe - first_name: Alberto full_name: Sesana, Alberto last_name: Sesana - first_name: Lisa full_name: Steinborn, Lisa last_name: Steinborn - first_name: Stefano full_name: Bianchi, Stefano last_name: Bianchi - first_name: Monica full_name: Colpi, Monica last_name: Colpi - first_name: Luciano full_name: del Valle, Luciano last_name: del Valle - first_name: Sándor full_name: Frey, Sándor last_name: Frey - first_name: Krisztina É. full_name: Gabányi, Krisztina É. last_name: Gabányi - first_name: Margherita full_name: Giustini, Margherita last_name: Giustini - first_name: Matteo full_name: Guainazzi, Matteo last_name: Guainazzi - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Noelia full_name: Herrera Ruiz, Noelia last_name: Herrera Ruiz - first_name: Rubén full_name: Herrero-Illana, Rubén last_name: Herrero-Illana - first_name: Kazushi full_name: Iwasawa, Kazushi last_name: Iwasawa - first_name: S. full_name: Komossa, S. last_name: Komossa - first_name: Davide full_name: Lena, Davide last_name: Lena - first_name: Nora full_name: Loiseau, Nora last_name: Loiseau - first_name: Miguel full_name: Perez-Torres, Miguel last_name: Perez-Torres - first_name: Enrico full_name: Piconcelli, Enrico last_name: Piconcelli - first_name: Marta full_name: Volonteri, Marta last_name: Volonteri citation: ama: 'De Rosa A, Vignali C, Bogdanović T, et al. The quest for dual and binary supermassive black holes: A multi-messenger view. New Astronomy Reviews. 2020;86. doi:10.1016/j.newar.2020.101525' apa: 'De Rosa, A., Vignali, C., Bogdanović, T., Capelo, P. R., Charisi, M., Dotti, M., … Volonteri, M. (2020). The quest for dual and binary supermassive black holes: A multi-messenger view. New Astronomy Reviews. Elsevier BV. https://doi.org/10.1016/j.newar.2020.101525' chicago: 'De Rosa, Alessandra, Cristian Vignali, Tamara Bogdanović, Pedro R. Capelo, Maria Charisi, Massimo Dotti, Bernd Husemann, et al. “The Quest for Dual and Binary Supermassive Black Holes: A Multi-Messenger View.” New Astronomy Reviews. Elsevier BV, 2020. https://doi.org/10.1016/j.newar.2020.101525.' ieee: 'A. De Rosa et al., “The quest for dual and binary supermassive black holes: A multi-messenger view,” New Astronomy Reviews, vol. 86. Elsevier BV, 2020.' ista: 'De Rosa A, Vignali C, Bogdanović T, Capelo PR, Charisi M, Dotti M, Husemann B, Lusso E, Mayer L, Paragi Z, Runnoe J, Sesana A, Steinborn L, Bianchi S, Colpi M, del Valle L, Frey S, Gabányi KÉ, Giustini M, Guainazzi M, Haiman Z, Herrera Ruiz N, Herrero-Illana R, Iwasawa K, Komossa S, Lena D, Loiseau N, Perez-Torres M, Piconcelli E, Volonteri M. 2020. The quest for dual and binary supermassive black holes: A multi-messenger view. New Astronomy Reviews. 86, 101525.' mla: 'De Rosa, Alessandra, et al. “The Quest for Dual and Binary Supermassive Black Holes: A Multi-Messenger View.” New Astronomy Reviews, vol. 86, 101525, Elsevier BV, 2020, doi:10.1016/j.newar.2020.101525.' short: A. De Rosa, C. Vignali, T. Bogdanović, P.R. Capelo, M. Charisi, M. Dotti, B. Husemann, E. Lusso, L. Mayer, Z. Paragi, J. Runnoe, A. Sesana, L. Steinborn, S. Bianchi, M. Colpi, L. del Valle, S. Frey, K.É. Gabányi, M. Giustini, M. Guainazzi, Z. Haiman, N. Herrera Ruiz, R. Herrero-Illana, K. Iwasawa, S. Komossa, D. Lena, N. Loiseau, M. Perez-Torres, E. Piconcelli, M. Volonteri, New Astronomy Reviews 86 (2020). date_created: 2024-09-05T13:07:32Z date_published: 2020-01-17T00:00:00Z date_updated: 2024-09-23T13:34:58Z day: '17' doi: 10.1016/j.newar.2020.101525 extern: '1' external_id: arxiv: - '2001.06293' intvolume: ' 86' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2001.06293' month: '01' oa: 1 oa_version: Preprint publication: New Astronomy Reviews publication_identifier: issn: - 1387-6473 publication_status: published publisher: Elsevier BV quality_controlled: '1' scopus_import: '1' status: public title: 'The quest for dual and binary supermassive black holes: A multi-messenger view' type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 86 year: '2020' ... --- _id: '17601' abstract: - lang: eng text: Using numerical hydrodynamics calculations and a novel method for densely sampling parameter space, we measure the accretion and torque on a binary system from a circumbinary disk. In agreement with some earlier studies, we find that the net torque on the binary is positive for mass ratios close to unity, and that accretion always drives the binary toward equal mass. Accretion variability depends sensitively on the numerical sink prescription, but the torque and relative accretion onto each component do not depend on the sink timescale. Positive torque and highly variable accretion occurs only for mass ratios greater than around 0.05. This means that for mass ratios below 0.05, the binary would migrate inward until the secondary accreted sufficient mass, after which it would execute a U-turn and migrate outward. We explore a range of viscosities, from α = 0.03 to α = 0.15, and find that this outward torque is proportional to the viscous torque, so that torque per unit accreted mass is independent of α. Dependence of accretion and torque on mass ratio is explored in detail, densely sampling mass ratios between 0.01 and unity. For mass ratio q > 0.2, accretion variability is found to exhibit a distinct sawtooth pattern, typically with a five-orbit cycle that provides a smoking gun prediction for variable quasars observed over long periods, as a potential means to confirm the presence of a binary. article_number: '25' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Paul C. full_name: Duffell, Paul C. last_name: Duffell - first_name: Daniel full_name: D’Orazio, Daniel last_name: D’Orazio - first_name: Andrea full_name: Derdzinski, Andrea last_name: Derdzinski - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: Andrew full_name: MacFadyen, Andrew last_name: MacFadyen - first_name: Anna L. full_name: Rosen, Anna L. last_name: Rosen - first_name: Jonathan full_name: Zrake, Jonathan last_name: Zrake citation: ama: 'Duffell PC, D’Orazio D, Derdzinski A, et al. Circumbinary disks: Accretion and torque as a function of mass ratio and disk viscosity. The Astrophysical Journal. 2020;901(1). doi:10.3847/1538-4357/abab95' apa: 'Duffell, P. C., D’Orazio, D., Derdzinski, A., Haiman, Z., MacFadyen, A., Rosen, A. L., & Zrake, J. (2020). Circumbinary disks: Accretion and torque as a function of mass ratio and disk viscosity. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/abab95' chicago: 'Duffell, Paul C., Daniel D’Orazio, Andrea Derdzinski, Zoltán Haiman, Andrew MacFadyen, Anna L. Rosen, and Jonathan Zrake. “Circumbinary Disks: Accretion and Torque as a Function of Mass Ratio and Disk Viscosity.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/abab95.' ieee: 'P. C. Duffell et al., “Circumbinary disks: Accretion and torque as a function of mass ratio and disk viscosity,” The Astrophysical Journal, vol. 901, no. 1. American Astronomical Society, 2020.' ista: 'Duffell PC, D’Orazio D, Derdzinski A, Haiman Z, MacFadyen A, Rosen AL, Zrake J. 2020. Circumbinary disks: Accretion and torque as a function of mass ratio and disk viscosity. The Astrophysical Journal. 901(1), 25.' mla: 'Duffell, Paul C., et al. “Circumbinary Disks: Accretion and Torque as a Function of Mass Ratio and Disk Viscosity.” The Astrophysical Journal, vol. 901, no. 1, 25, American Astronomical Society, 2020, doi:10.3847/1538-4357/abab95.' short: P.C. Duffell, D. D’Orazio, A. Derdzinski, Z. Haiman, A. MacFadyen, A.L. Rosen, J. Zrake, The Astrophysical Journal 901 (2020). date_created: 2024-09-05T13:08:20Z date_published: 2020-09-17T00:00:00Z date_updated: 2024-09-23T13:39:03Z day: '17' doi: 10.3847/1538-4357/abab95 extern: '1' external_id: arxiv: - '1911.05506' intvolume: ' 901' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.1911.05506' month: '09' oa: 1 oa_version: Preprint publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: 'Circumbinary disks: Accretion and torque as a function of mass ratio and disk viscosity' type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 901 year: '2020' ... --- _id: '17604' abstract: - lang: eng text: 'Numerical studies of gas accretion onto supermassive black hole binaries (SMBHBs) have generally been limited to conditions where the circumbinary disk (CBD) is 10-100 times thicker than expected for disks in active galactic nuclei (AGN). This discrepancy arises from technical limitations, and also from publication bias toward replicating fiducial numerical models. Here we present the first systematic study of how the binary''s orbital evolution varies with disk scale height. We report three key results: (1) Binary orbital evolution switches from outspiralling for warm disks (aspect ratio ~0.1), to inspiralling for more realistic cooler, thinner disks at a critical aspect ratio ~0.04, corresponding to orbital Mach number ~25. (2) The net torque on the binary arises from a competition between positive torque from gas orbiting close to the black holes, and negative torque from the inner edge of the CBD, which is denser for thinner disks. This leads to increasingly negative net torques on the binary for increasingly thin disks. (3) The accretion rate is modestly suppressed with increasing Mach number. We discuss how our results may influence modeling of the nano-Hz gravitational wave background, as well as estimates of the LISA merger event rate.' article_number: '43' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Christopher full_name: Tiede, Christopher last_name: Tiede - first_name: Jonathan full_name: Zrake, Jonathan last_name: Zrake - first_name: Andrew full_name: MacFadyen, Andrew last_name: MacFadyen - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman citation: ama: Tiede C, Zrake J, MacFadyen A, Haiman Z. Gas-driven inspiral of binaries in thin accretion disks. The Astrophysical Journal. 2020;900(1). doi:10.3847/1538-4357/aba432 apa: Tiede, C., Zrake, J., MacFadyen, A., & Haiman, Z. (2020). Gas-driven inspiral of binaries in thin accretion disks. The Astrophysical Journal. American Astronomical Society. https://doi.org/10.3847/1538-4357/aba432 chicago: Tiede, Christopher, Jonathan Zrake, Andrew MacFadyen, and Zoltán Haiman. “Gas-Driven Inspiral of Binaries in Thin Accretion Disks.” The Astrophysical Journal. American Astronomical Society, 2020. https://doi.org/10.3847/1538-4357/aba432. ieee: C. Tiede, J. Zrake, A. MacFadyen, and Z. Haiman, “Gas-driven inspiral of binaries in thin accretion disks,” The Astrophysical Journal, vol. 900, no. 1. American Astronomical Society, 2020. ista: Tiede C, Zrake J, MacFadyen A, Haiman Z. 2020. Gas-driven inspiral of binaries in thin accretion disks. The Astrophysical Journal. 900(1), 43. mla: Tiede, Christopher, et al. “Gas-Driven Inspiral of Binaries in Thin Accretion Disks.” The Astrophysical Journal, vol. 900, no. 1, 43, American Astronomical Society, 2020, doi:10.3847/1538-4357/aba432. short: C. Tiede, J. Zrake, A. MacFadyen, Z. Haiman, The Astrophysical Journal 900 (2020). date_created: 2024-09-05T13:12:20Z date_published: 2020-08-28T00:00:00Z date_updated: 2024-09-23T13:59:30Z day: '28' doi: 10.3847/1538-4357/aba432 extern: '1' external_id: arxiv: - '2005.09555' intvolume: ' 900' issue: '1' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2005.09555' month: '08' oa: 1 oa_version: Preprint publication: The Astrophysical Journal publication_identifier: issn: - 0004-637X - 1538-4357 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: Gas-driven inspiral of binaries in thin accretion disks type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 900 year: '2020' ... --- _id: '17605' abstract: - lang: eng text: Despite the rapidly growing number of stellar-mass binary black hole mergers discovered through gravitational waves, the origin of these binaries is still not known. In galactic centers, black holes can be brought to each others' proximity by dynamical processes, resulting in mergers. It is also possible that black holes formed in previous mergers encounter new black holes, resulting in so-called hierarchical mergers. Hierarchical events carry signatures such as higher-than-usual black hole mass and spin. Here we show that the recently reported gravitational-wave candidate, GW170817A, could be the result of such a hierarchical merger. In particular, its chirp mass ∼40 M⊙ and effective spin of χeff ∼ 0.5 are the typically expected values from hierarchical mergers within the disks of active galactic nuclei. We find that the reconstructed parameters of GW170817A strongly favor a hierarchical merger origin over having been produced by an isolated binary origin (with an odds ratio of > 10^3). article_number: L20 article_processing_charge: No article_type: original arxiv: 1 author: - first_name: V. full_name: Gayathri, V. last_name: Gayathri - first_name: I. full_name: Bartos, I. last_name: Bartos - first_name: Zoltán full_name: Haiman, Zoltán id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36 last_name: Haiman - first_name: S. full_name: Klimenko, S. last_name: Klimenko - first_name: B. full_name: Kocsis, B. last_name: Kocsis - first_name: S. full_name: Márka, S. last_name: Márka - first_name: Y. full_name: Yang, Y. last_name: Yang citation: ama: Gayathri V, Bartos I, Haiman Z, et al. GW170817A as a hierarchical black hole merger. The Astrophysical Journal Letters. 2020;890(2). doi:10.3847/2041-8213/ab745d apa: Gayathri, V., Bartos, I., Haiman, Z., Klimenko, S., Kocsis, B., Márka, S., & Yang, Y. (2020). GW170817A as a hierarchical black hole merger. The Astrophysical Journal Letters. American Astronomical Society. https://doi.org/10.3847/2041-8213/ab745d chicago: Gayathri, V., I. Bartos, Zoltán Haiman, S. Klimenko, B. Kocsis, S. Márka, and Y. Yang. “GW170817A as a Hierarchical Black Hole Merger.” The Astrophysical Journal Letters. American Astronomical Society, 2020. https://doi.org/10.3847/2041-8213/ab745d. ieee: V. Gayathri et al., “GW170817A as a hierarchical black hole merger,” The Astrophysical Journal Letters, vol. 890, no. 2. American Astronomical Society, 2020. ista: Gayathri V, Bartos I, Haiman Z, Klimenko S, Kocsis B, Márka S, Yang Y. 2020. GW170817A as a hierarchical black hole merger. The Astrophysical Journal Letters. 890(2), L20. mla: Gayathri, V., et al. “GW170817A as a Hierarchical Black Hole Merger.” The Astrophysical Journal Letters, vol. 890, no. 2, L20, American Astronomical Society, 2020, doi:10.3847/2041-8213/ab745d. short: V. Gayathri, I. Bartos, Z. Haiman, S. Klimenko, B. Kocsis, S. Márka, Y. Yang, The Astrophysical Journal Letters 890 (2020). date_created: 2024-09-05T13:13:33Z date_published: 2020-02-18T00:00:00Z date_updated: 2024-09-23T14:04:29Z day: '18' doi: 10.3847/2041-8213/ab745d extern: '1' external_id: arxiv: - '1911.11142' intvolume: ' 890' issue: '2' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.1911.11142' month: '02' oa: 1 oa_version: Preprint publication: The Astrophysical Journal Letters publication_identifier: issn: - 2041-8205 - 2041-8213 publication_status: published publisher: American Astronomical Society quality_controlled: '1' scopus_import: '1' status: public title: GW170817A as a hierarchical black hole merger type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 890 year: '2020' ...