--- _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' fulldoi: https://doi.org/10.1146/annurev-astro-120419-014455 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' fulldoi: https://doi.org/10.21105/astro.2006.14625 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' fulldoi: https://doi.org/10.3847/1538-4357/ab7922 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' fulldoi: https://doi.org/10.3847/1538-4357/abad31 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' fulldoi: https://doi.org/10.3847/1538-4357/ab9b8c 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' fulldoi: https://doi.org/10.1103/physrevd.101.083016 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' fulldoi: https://doi.org/10.1093/mnras/staa3057 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' fulldoi: https://doi.org/10.3847/1538-4357/ab91b4 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' fulldoi: https://doi.org/10.1103/physrevd.102.123506 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' fulldoi: https://doi.org/10.1016/j.newar.2020.101525 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' fulldoi: https://doi.org/10.3847/1538-4357/abab95 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' fulldoi: https://doi.org/10.3847/1538-4357/aba432 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' fulldoi: https://doi.org/10.3847/2041-8213/ab745d 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' ... --- _id: '17607' abstract: - lang: eng text: The heaviest neutron stars and lightest black holes expected to be produced by stellar evolution leave the mass-range 2.2 M⊙≲m≲5 M⊙ largely unpopulated. Objects found in this so-called lower mass gap likely originate from a distinct astrophysical process. Such an object, with mass 2.6 M⊙ was recently detected in the binary merger GW190814 through gravitational waves by LIGO/Virgo. Here we show that black holes in the mass gap are naturally assembled through mergers and accretion in AGN disks, and can subsequently participate in additional mergers. We compute the properties of AGN-assisted mergers involving neutron stars and black holes, accounting for accretion. We find that mergers in which one of the objects is in the lower mass gap represent up to 4% of AGN-assisted mergers detectable by LIGO/Virgo. The lighter object of GW190814, with mass 2.6 M⊙, could have grown in an AGN disk through accretion. We find that the unexpectedly high total mass of 3.4 M⊙ observed in the neutron star merger GW190425 may also be due to accretion in an AGN disk. article_number: L34 article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Y. full_name: Yang, Y. last_name: Yang - 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: M. full_name: Safarzadeh, M. last_name: Safarzadeh - first_name: H. full_name: Tagawa, H. last_name: Tagawa citation: ama: Yang Y, Gayathri V, Bartos I, Haiman Z, Safarzadeh M, Tagawa H. Black hole formation in the lower mass gap through mergers and accretion in AGN disks. The Astrophysical Journal Letters. 2020;901(2). doi:10.3847/2041-8213/abb940 apa: Yang, Y., Gayathri, V., Bartos, I., Haiman, Z., Safarzadeh, M., & Tagawa, H. (2020). Black hole formation in the lower mass gap through mergers and accretion in AGN disks. The Astrophysical Journal Letters. American Astronomical Society. https://doi.org/10.3847/2041-8213/abb940 chicago: Yang, Y., V. Gayathri, I. Bartos, Zoltán Haiman, M. Safarzadeh, and H. Tagawa. “Black Hole Formation in the Lower Mass Gap through Mergers and Accretion in AGN Disks.” The Astrophysical Journal Letters. American Astronomical Society, 2020. https://doi.org/10.3847/2041-8213/abb940. ieee: Y. Yang, V. Gayathri, I. Bartos, Z. Haiman, M. Safarzadeh, and H. Tagawa, “Black hole formation in the lower mass gap through mergers and accretion in AGN disks,” The Astrophysical Journal Letters, vol. 901, no. 2. American Astronomical Society, 2020. ista: Yang Y, Gayathri V, Bartos I, Haiman Z, Safarzadeh M, Tagawa H. 2020. Black hole formation in the lower mass gap through mergers and accretion in AGN disks. The Astrophysical Journal Letters. 901(2), L34. mla: Yang, Y., et al. “Black Hole Formation in the Lower Mass Gap through Mergers and Accretion in AGN Disks.” The Astrophysical Journal Letters, vol. 901, no. 2, L34, American Astronomical Society, 2020, doi:10.3847/2041-8213/abb940. short: Y. Yang, V. Gayathri, I. Bartos, Z. Haiman, M. Safarzadeh, H. Tagawa, The Astrophysical Journal Letters 901 (2020). date_created: 2024-09-05T13:15:59Z date_published: 2020-10-01T00:00:00Z date_updated: 2024-09-23T14:16:49Z day: '01' doi: 10.3847/2041-8213/abb940 extern: '1' external_id: arxiv: - '2007.04781' fulldoi: https://doi.org/10.3847/2041-8213/abb940 intvolume: ' 901' issue: '2' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2007.04781' month: '10' 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: Black hole formation in the lower mass gap through mergers and accretion in AGN disks type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 901 year: '2020' ... --- OA_type: closed access _id: '17902' abstract: - lang: eng text: Probing structural changes of a molecule induced by charge transfer is important for understanding the physicochemical properties of molecules and developing new electronic devices. Here, we interrogate the structural changes of a single diketopyrrolopyrrole (DPP) molecule induced by charge transport at a high bias using scanning tunneling microscope break junction (STM-BJ) techniques. Specifically, we demonstrate that application of a high bias increases the average nonresonant conductance of single Au–DPP–Au junctions. We infer from the increased conductance that resonant charge transport induces planarization of the molecular backbone. We further show that this conformational planarization is assisted by thermally activated junction reorganization. The planarization only occurs under specific electronic conditions, which we rationalize by ab initio calculations. These results emphasize the need for a comprehensive view of single-molecule junctions which includes both the electronic properties and structure of the molecules and the electrodes when designing electrically driven single-molecule motors. article_processing_charge: No article_type: letter_note author: - first_name: Yaping full_name: Zang, Yaping last_name: Zang - first_name: E-Dean full_name: Fung, E-Dean last_name: Fung - first_name: Tianren full_name: Fu, Tianren last_name: Fu - first_name: Suman full_name: Ray, Suman last_name: Ray - first_name: Marc H. full_name: Garner, Marc H. last_name: Garner - first_name: Anders full_name: Borges, Anders last_name: Borges - first_name: Michael L. full_name: Steigerwald, Michael L. last_name: Steigerwald - first_name: Satish full_name: Patil, Satish last_name: Patil - first_name: Gemma full_name: Solomon, Gemma last_name: Solomon - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 citation: ama: Zang Y, Fung E-D, Fu T, et al. Voltage-induced single-molecule junction planarization. Nano Letters. 2020;21(1):673-679. doi:10.1021/acs.nanolett.0c04260 apa: Zang, Y., Fung, E.-D., Fu, T., Ray, S., Garner, M. H., Borges, A., … Venkataraman, L. (2020). Voltage-induced single-molecule junction planarization. Nano Letters. American Chemical Society. https://doi.org/10.1021/acs.nanolett.0c04260 chicago: Zang, Yaping, E-Dean Fung, Tianren Fu, Suman Ray, Marc H. Garner, Anders Borges, Michael L. Steigerwald, Satish Patil, Gemma Solomon, and Latha Venkataraman. “Voltage-Induced Single-Molecule Junction Planarization.” Nano Letters. American Chemical Society, 2020. https://doi.org/10.1021/acs.nanolett.0c04260. ieee: Y. Zang et al., “Voltage-induced single-molecule junction planarization,” Nano Letters, vol. 21, no. 1. American Chemical Society, pp. 673–679, 2020. ista: Zang Y, Fung E-D, Fu T, Ray S, Garner MH, Borges A, Steigerwald ML, Patil S, Solomon G, Venkataraman L. 2020. Voltage-induced single-molecule junction planarization. Nano Letters. 21(1), 673–679. mla: Zang, Yaping, et al. “Voltage-Induced Single-Molecule Junction Planarization.” Nano Letters, vol. 21, no. 1, American Chemical Society, 2020, pp. 673–79, doi:10.1021/acs.nanolett.0c04260. short: Y. Zang, E.-D. Fung, T. Fu, S. Ray, M.H. Garner, A. Borges, M.L. Steigerwald, S. Patil, G. Solomon, L. Venkataraman, Nano Letters 21 (2020) 673–679. date_created: 2024-09-09T06:48:30Z date_published: 2020-12-18T00:00:00Z date_updated: 2024-12-10T10:26:22Z day: '18' doi: 10.1021/acs.nanolett.0c04260 extern: '1' external_id: pmid: - '33337876' fulldoi: https://doi.org/10.1021/acs.nanolett.0c04260 intvolume: ' 21' issue: '1' language: - iso: eng month: '12' oa_version: None page: 673-679 pmid: 1 publication: Nano Letters publication_identifier: eissn: - 1530-6992 issn: - 1530-6984 publication_status: published publisher: American Chemical Society quality_controlled: '1' scopus_import: '1' status: public title: Voltage-induced single-molecule junction planarization type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 21 year: '2020' ... --- OA_type: closed access _id: '17903' abstract: - lang: eng text: Light emission from tunnel junctions are a potential photon source for nanophotonic applications. Surprisingly, the photons emitted can have energies exceeding the energy supplied to the electrons by the bias. Three mechanisms for generating these so-called overbias photons have been proposed, but the relationship between these mechanisms has not been clarified. In this work, we argue that multielectron processes provide the best framework for understanding overbias light emission in tunnel junctions. Experimentally, we demonstrate for the first time that the superlinear dependence of emission on conductance predicted by this theory is robust to the temperature of the tunnel junction, indicating that tunnel junctions are a promising candidate for electrically driven broadband photon sources. article_processing_charge: No article_type: letter_note author: - first_name: E-Dean full_name: Fung, E-Dean last_name: Fung - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 citation: ama: 'Fung E-D, Venkataraman L. Too cool for blackbody radiation: Overbias photon emission in ambient STM due to multielectron processes. Nano Letters. 2020;20(12):8912-8918. doi:10.1021/acs.nanolett.0c03994' apa: 'Fung, E.-D., & Venkataraman, L. (2020). Too cool for blackbody radiation: Overbias photon emission in ambient STM due to multielectron processes. Nano Letters. American Chemical Society. https://doi.org/10.1021/acs.nanolett.0c03994' chicago: 'Fung, E-Dean, and Latha Venkataraman. “Too Cool for Blackbody Radiation: Overbias Photon Emission in Ambient STM Due to Multielectron Processes.” Nano Letters. American Chemical Society, 2020. https://doi.org/10.1021/acs.nanolett.0c03994.' ieee: 'E.-D. Fung and L. Venkataraman, “Too cool for blackbody radiation: Overbias photon emission in ambient STM due to multielectron processes,” Nano Letters, vol. 20, no. 12. American Chemical Society, pp. 8912–8918, 2020.' ista: 'Fung E-D, Venkataraman L. 2020. Too cool for blackbody radiation: Overbias photon emission in ambient STM due to multielectron processes. Nano Letters. 20(12), 8912–8918.' mla: 'Fung, E. Dean, and Latha Venkataraman. “Too Cool for Blackbody Radiation: Overbias Photon Emission in Ambient STM Due to Multielectron Processes.” Nano Letters, vol. 20, no. 12, American Chemical Society, 2020, pp. 8912–18, doi:10.1021/acs.nanolett.0c03994.' short: E.-D. Fung, L. Venkataraman, Nano Letters 20 (2020) 8912–8918. date_created: 2024-09-09T07:12:19Z date_published: 2020-11-18T00:00:00Z date_updated: 2024-12-10T10:28:52Z day: '18' doi: 10.1021/acs.nanolett.0c03994 extern: '1' external_id: pmid: - '33206534' fulldoi: https://doi.org/10.1021/acs.nanolett.0c03994 intvolume: ' 20' issue: '12' language: - iso: eng month: '11' oa_version: None page: 8912-8918 pmid: 1 publication: Nano Letters publication_identifier: eissn: - 1530-6992 issn: - 1530-6984 publication_status: published publisher: American Chemical Society quality_controlled: '1' scopus_import: '1' status: public title: 'Too cool for blackbody radiation: Overbias photon emission in ambient STM due to multielectron processes' type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 20 year: '2020' ... --- OA_type: closed access _id: '17904' abstract: - lang: eng text: The creation of stable molecular monolayers on metallic surfaces is a fundamental challenge of surface chemistry. N-Heterocyclic carbenes (NHCs) were recently shown to form self-assembled monolayers that are significantly more stable than the traditional thiols on Au system. Here we theoretically and experimentally demonstrate that the smallest cyclic carbene, cyclopropenylidene, binds even more strongly than NHCs to Au surfaces without altering the surface structure. We deposit bis(diisopropylamino)cyclopropenylidene (BAC) on Au(111) using the molecular adduct BAC–CO2 as a precursor and determine the structure, geometry, and behavior of the surface-bound molecules through high-resolution X-ray photoelectron spectroscopy, atomic force microscopy, and scanning tunneling microscopy. Our experiments are supported by density functional theory calculations of the molecular binding energy of BAC on Au(111) and its electronic structure. Our work is the first demonstration of surface modification with a stable carbene other than NHC; more broadly, it drives further exploration of various carbenes on metal surfaces. article_processing_charge: No article_type: letter_note author: - first_name: Evan A. full_name: Doud, Evan A. last_name: Doud - first_name: Rachel L. full_name: Starr, Rachel L. last_name: Starr - first_name: Gregor full_name: Kladnik, Gregor last_name: Kladnik - first_name: Anastasia full_name: Voevodin, Anastasia last_name: Voevodin - first_name: Enrique full_name: Montes, Enrique last_name: Montes - first_name: Narendra P. full_name: Arasu, Narendra P. last_name: Arasu - first_name: Yaping full_name: Zang, Yaping last_name: Zang - first_name: Percy full_name: Zahl, Percy last_name: Zahl - first_name: Alberto full_name: Morgante, Alberto last_name: Morgante - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 - first_name: Héctor full_name: Vázquez, Héctor last_name: Vázquez - first_name: Dean full_name: Cvetko, Dean last_name: Cvetko - first_name: Xavier full_name: Roy, Xavier last_name: Roy citation: ama: Doud EA, Starr RL, Kladnik G, et al. Cyclopropenylidenes as strong carbene anchoring groups on Au surfaces. Journal of the American Chemical Society. 2020;142(47):19902-19906. doi:10.1021/jacs.0c10743 apa: Doud, E. A., Starr, R. L., Kladnik, G., Voevodin, A., Montes, E., Arasu, N. P., … Roy, X. (2020). Cyclopropenylidenes as strong carbene anchoring groups on Au surfaces. Journal of the American Chemical Society. American Chemical Society. https://doi.org/10.1021/jacs.0c10743 chicago: Doud, Evan A., Rachel L. Starr, Gregor Kladnik, Anastasia Voevodin, Enrique Montes, Narendra P. Arasu, Yaping Zang, et al. “Cyclopropenylidenes as Strong Carbene Anchoring Groups on Au Surfaces.” Journal of the American Chemical Society. American Chemical Society, 2020. https://doi.org/10.1021/jacs.0c10743. ieee: E. A. Doud et al., “Cyclopropenylidenes as strong carbene anchoring groups on Au surfaces,” Journal of the American Chemical Society, vol. 142, no. 47. American Chemical Society, pp. 19902–19906, 2020. ista: Doud EA, Starr RL, Kladnik G, Voevodin A, Montes E, Arasu NP, Zang Y, Zahl P, Morgante A, Venkataraman L, Vázquez H, Cvetko D, Roy X. 2020. Cyclopropenylidenes as strong carbene anchoring groups on Au surfaces. Journal of the American Chemical Society. 142(47), 19902–19906. mla: Doud, Evan A., et al. “Cyclopropenylidenes as Strong Carbene Anchoring Groups on Au Surfaces.” Journal of the American Chemical Society, vol. 142, no. 47, American Chemical Society, 2020, pp. 19902–06, doi:10.1021/jacs.0c10743. short: E.A. Doud, R.L. Starr, G. Kladnik, A. Voevodin, E. Montes, N.P. Arasu, Y. Zang, P. Zahl, A. Morgante, L. Venkataraman, H. Vázquez, D. Cvetko, X. Roy, Journal of the American Chemical Society 142 (2020) 19902–19906. date_created: 2024-09-09T07:13:45Z date_published: 2020-11-11T00:00:00Z date_updated: 2024-12-10T10:34:58Z day: '11' doi: 10.1021/jacs.0c10743 extern: '1' external_id: pmid: - '33175526' fulldoi: https://doi.org/10.1021/jacs.0c10743 intvolume: ' 142' issue: '47' language: - iso: eng month: '11' oa_version: None page: 19902-19906 pmid: 1 publication: Journal of the American Chemical Society publication_identifier: eissn: - 1520-5126 issn: - 0002-7863 publication_status: published publisher: American Chemical Society quality_controlled: '1' scopus_import: '1' status: public title: Cyclopropenylidenes as strong carbene anchoring groups on Au surfaces type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 142 year: '2020' ... --- DOAJ_listed: '1' OA_place: publisher OA_type: gold _id: '17905' abstract: - lang: eng text: A series of four oligomers of cyclopentadithiophene-vinylenes end capped with pyridine groups was prepared and their optical and electronic properties studied. Treatment with trifluoroacetic acid (TFA) leads to the bisprotonation of the nitrogens of the pyridine, which has an important impact on the optical properties. Excess treatment with TFA provokes the oxidation of the conjugated core, generating radical cations and dications. The ease of the TFA treatment in solution was extended to protonation in the solid-state where further characterization of the neutral and TFA-treated samples was carried out in electrically active substrates in organic field-effect transistors. Finally, the new molecules were found to be excellent conductors in single-molecule junctions thanks to strong electron delocalization and resonance orbital mediated transport. These studies show the opening of a spectrum of possibilities by suitable terminal substitution of π-cores. article_processing_charge: Yes article_type: original author: - first_name: Fernando G. full_name: Guijarro, Fernando G. last_name: Guijarro - first_name: Samara full_name: Medina Rivero, Samara last_name: Medina Rivero - first_name: Suman full_name: Gunasekaran, Suman last_name: Gunasekaran - first_name: Iratxe full_name: Arretxea, Iratxe last_name: Arretxea - first_name: Rocío full_name: Ponce Ortiz, Rocío last_name: Ponce Ortiz - first_name: Rubén full_name: Caballero, Rubén last_name: Caballero - first_name: Pilar de la full_name: Cruz, Pilar de la last_name: Cruz - first_name: Fernando full_name: Langa, Fernando last_name: Langa - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 - first_name: Juan full_name: Casado, Juan last_name: Casado citation: ama: Guijarro FG, Medina Rivero S, Gunasekaran S, et al. Synthesis and electronic properties of pyridine end-capped cyclopentadithiophene-vinylene oligomers. RSC Advances. 2020;10(68):41264-41271. doi:10.1039/d0ra08220a apa: Guijarro, F. G., Medina Rivero, S., Gunasekaran, S., Arretxea, I., Ponce Ortiz, R., Caballero, R., … Casado, J. (2020). Synthesis and electronic properties of pyridine end-capped cyclopentadithiophene-vinylene oligomers. RSC Advances. Royal Society of Chemistry. https://doi.org/10.1039/d0ra08220a chicago: Guijarro, Fernando G., Samara Medina Rivero, Suman Gunasekaran, Iratxe Arretxea, Rocío Ponce Ortiz, Rubén Caballero, Pilar de la Cruz, Fernando Langa, Latha Venkataraman, and Juan Casado. “Synthesis and Electronic Properties of Pyridine End-Capped Cyclopentadithiophene-Vinylene Oligomers.” RSC Advances. Royal Society of Chemistry, 2020. https://doi.org/10.1039/d0ra08220a. ieee: F. G. Guijarro et al., “Synthesis and electronic properties of pyridine end-capped cyclopentadithiophene-vinylene oligomers,” RSC Advances, vol. 10, no. 68. Royal Society of Chemistry, pp. 41264–41271, 2020. ista: Guijarro FG, Medina Rivero S, Gunasekaran S, Arretxea I, Ponce Ortiz R, Caballero R, Cruz P de la, Langa F, Venkataraman L, Casado J. 2020. Synthesis and electronic properties of pyridine end-capped cyclopentadithiophene-vinylene oligomers. RSC Advances. 10(68), 41264–41271. mla: Guijarro, Fernando G., et al. “Synthesis and Electronic Properties of Pyridine End-Capped Cyclopentadithiophene-Vinylene Oligomers.” RSC Advances, vol. 10, no. 68, Royal Society of Chemistry, 2020, pp. 41264–71, doi:10.1039/d0ra08220a. short: F.G. Guijarro, S. Medina Rivero, S. Gunasekaran, I. Arretxea, R. Ponce Ortiz, R. Caballero, P. de la Cruz, F. Langa, L. Venkataraman, J. Casado, RSC Advances 10 (2020) 41264–41271. date_created: 2024-09-09T07:14:34Z date_published: 2020-11-11T00:00:00Z date_updated: 2024-12-10T10:38:07Z day: '11' doi: 10.1039/d0ra08220a extern: '1' external_id: pmid: - '35516533' fulldoi: https://doi.org/10.1039/d0ra08220a intvolume: ' 10' issue: '68' language: - iso: eng license: https://creativecommons.org/licenses/by-nc/3.0/ month: '11' oa_version: Published Version page: 41264-41271 pmid: 1 publication: RSC Advances publication_identifier: issn: - 2046-2069 publication_status: published publisher: Royal Society of Chemistry quality_controlled: '1' scopus_import: '1' status: public title: Synthesis and electronic properties of pyridine end-capped cyclopentadithiophene-vinylene oligomers tmp: image: /images/cc_by_nc.png legal_code_url: https://creativecommons.org/licenses/by-nc/3.0/legalcode name: Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0) short: CC BY-NC (3.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 10 year: '2020' ... --- OA_type: closed access _id: '17906' abstract: - lang: eng text: One-dimensional sp-hybridized carbon wires, including cumulenes and polyynes, can be regarded as finite versions of carbynes. They are likely to be good candidates for molecular-scale conducting wires as they are predicted to have a high-conductance. In this study, we first characterize the single-molecule conductance of a series of cumulenes and polyynes with a backbone ranging in length from 4 to 8 carbon atoms, including [7]cumulene, the longest cumulenic carbon wire studied to date for molecular electronics. We observe different length dependence of conductance when comparing these two forms of carbon wires. Polyynes exhibit conductance decays with increasing molecular length, while cumulenes show a conductance increase with increasing molecular length. Their distinct conducting behaviors are attributed to their different bond length alternation, which is supported by theoretical calculations. This study confirms the long-standing theoretical predictions on sp-hybridized carbon wires and demonstrates that cumulenes can form highly conducting molecular wires. article_processing_charge: No article_type: letter_note author: - first_name: Yaping full_name: Zang, Yaping last_name: Zang - first_name: Tianren full_name: Fu, Tianren last_name: Fu - first_name: Qi full_name: Zou, Qi last_name: Zou - first_name: Fay full_name: Ng, Fay last_name: Ng - first_name: Hexing full_name: Li, Hexing last_name: Li - first_name: Michael L. full_name: Steigerwald, Michael L. last_name: Steigerwald - first_name: Colin full_name: Nuckolls, Colin last_name: Nuckolls - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 citation: ama: Zang Y, Fu T, Zou Q, et al. Cumulene wires display increasing conductance with increasing length. Nano Letters. 2020;20(11):8415-8419. doi:10.1021/acs.nanolett.0c03794 apa: Zang, Y., Fu, T., Zou, Q., Ng, F., Li, H., Steigerwald, M. L., … Venkataraman, L. (2020). Cumulene wires display increasing conductance with increasing length. Nano Letters. American Chemical Society. https://doi.org/10.1021/acs.nanolett.0c03794 chicago: Zang, Yaping, Tianren Fu, Qi Zou, Fay Ng, Hexing Li, Michael L. Steigerwald, Colin Nuckolls, and Latha Venkataraman. “Cumulene Wires Display Increasing Conductance with Increasing Length.” Nano Letters. American Chemical Society, 2020. https://doi.org/10.1021/acs.nanolett.0c03794. ieee: Y. Zang et al., “Cumulene wires display increasing conductance with increasing length,” Nano Letters, vol. 20, no. 11. American Chemical Society, pp. 8415–8419, 2020. ista: Zang Y, Fu T, Zou Q, Ng F, Li H, Steigerwald ML, Nuckolls C, Venkataraman L. 2020. Cumulene wires display increasing conductance with increasing length. Nano Letters. 20(11), 8415–8419. mla: Zang, Yaping, et al. “Cumulene Wires Display Increasing Conductance with Increasing Length.” Nano Letters, vol. 20, no. 11, American Chemical Society, 2020, pp. 8415–19, doi:10.1021/acs.nanolett.0c03794. short: Y. Zang, T. Fu, Q. Zou, F. Ng, H. Li, M.L. Steigerwald, C. Nuckolls, L. Venkataraman, Nano Letters 20 (2020) 8415–8419. date_created: 2024-09-09T07:16:20Z date_published: 2020-10-23T00:00:00Z date_updated: 2024-12-10T10:41:40Z day: '23' doi: 10.1021/acs.nanolett.0c03794 extern: '1' external_id: pmid: - '33095021' fulldoi: https://doi.org/10.1021/acs.nanolett.0c03794 intvolume: ' 20' issue: '11' language: - iso: eng month: '10' oa_version: None page: 8415-8419 pmid: 1 publication: Nano Letters publication_identifier: eissn: - 1530-6992 issn: - 1530-6984 publication_status: published publisher: American Chemical Society quality_controlled: '1' scopus_import: '1' status: public title: Cumulene wires display increasing conductance with increasing length type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 20 year: '2020' ... --- OA_type: closed access _id: '17907' abstract: - lang: eng text: Carbyne is a linear allotrope of carbon that is composed of a chain of sp-hybridized carbon atoms. Through appropriate engineering of the chain termination, carbyne can harbor helical states where the π-electron delocalization twists along the axis of the chain. Herein, we present a comprehensive analysis of these helical states at the tight-binding level. We demonstrate that, in general, the molecular orbital coefficients of the helical states trace out an ellipse, in analogy to elliptically polarized light. Helical states can be realized in a model, inspired by the structure of cumulene, which considers a chain terminated by sp2-hybridized atoms oriented at a nontrivial dihedral angle. We provide a complete analytic solution for this model. Additionally, we present a variation of the model that yields perfect helical states that trace out a circle as opposed to an ellipse. Our results provide a deeper understanding of helical states and lay a foundation for more advanced levels of theory. article_number: '124304 ' article_processing_charge: No article_type: original author: - first_name: Suman full_name: Gunasekaran, Suman last_name: Gunasekaran - first_name: Latha full_name: Venkataraman, Latha id: 9ebb78a5-cc0d-11ee-8322-fae086a32caf last_name: Venkataraman orcid: 0000-0002-6957-6089 citation: ama: Gunasekaran S, Venkataraman L. Tight-binding analysis of helical states in carbyne. The Journal of Chemical Physics. 2020;153(12). doi:10.1063/5.0021146 apa: Gunasekaran, S., & Venkataraman, L. (2020). Tight-binding analysis of helical states in carbyne. The Journal of Chemical Physics. AIP Publishing. https://doi.org/10.1063/5.0021146 chicago: Gunasekaran, Suman, and Latha Venkataraman. “Tight-Binding Analysis of Helical States in Carbyne.” The Journal of Chemical Physics. AIP Publishing, 2020. https://doi.org/10.1063/5.0021146. ieee: S. Gunasekaran and L. Venkataraman, “Tight-binding analysis of helical states in carbyne,” The Journal of Chemical Physics, vol. 153, no. 12. AIP Publishing, 2020. ista: Gunasekaran S, Venkataraman L. 2020. Tight-binding analysis of helical states in carbyne. The Journal of Chemical Physics. 153(12), 124304. mla: Gunasekaran, Suman, and Latha Venkataraman. “Tight-Binding Analysis of Helical States in Carbyne.” The Journal of Chemical Physics, vol. 153, no. 12, 124304, AIP Publishing, 2020, doi:10.1063/5.0021146. short: S. Gunasekaran, L. Venkataraman, The Journal of Chemical Physics 153 (2020). date_created: 2024-09-09T07:17:20Z date_published: 2020-09-28T00:00:00Z date_updated: 2024-12-10T10:46:25Z day: '28' doi: 10.1063/5.0021146 extern: '1' external_id: pmid: - '33003709' fulldoi: https://doi.org/10.1063/5.0021146 intvolume: ' 153' issue: '12' language: - iso: eng month: '09' oa_version: None pmid: 1 publication: The Journal of Chemical Physics publication_identifier: eissn: - 1089-7690 issn: - 0021-9606 publication_status: published publisher: AIP Publishing quality_controlled: '1' scopus_import: '1' status: public title: Tight-binding analysis of helical states in carbyne type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 153 year: '2020' ...