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20142026
most citedThe NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background

1.5k citations · 5.2k across the 63 of their papers we have counts for

collaborators

68 papers

astro-ph.HE2026

Constraints on Supermassive Black Hole Binaries from the Lack of Resolvable Sources in the NANOGrav 15-yr Dataset

Emiko C. Gardiner, Kayhan Gültekin, Philippe Turgeon +116

Pulsar timing arrays (PTAs) have found evidence of a gravitational wave background (GWB) consistent with a population of supermassive black hole binaries (SMBHBs), but have not yet…

astro-ph.IM2026

Pulsar Timing Array Sensitivity to Anisotropy: Empirical Sensitivity Curves, Scaling Relations, and the Multi-Resolution Pixel Basis

Taha T. Moursy, Nihan S. Pol, Gabriella Agazie +115

We quantify pulsar timing array (PTA) sensitivity to anisotropy in the gravitational wave background using the cross-correlation based Fisher information matrix in the pixel and sp…

astro-ph.HE2026

QuickGWecc: Fast Bayesian pipeline for searching eccentric binaries in pulsar timing array data

Lankeswar Dey, Bence Bécsy, Abhimanyu Susobhanan +1

Recent pulsar timing array (PTA) results have provided evidence for the presence of a nanohertz gravitational wave (GW) background, most likely originating from a population of sup…

astro-ph.CO2026

The NANOGrav 15 yr Data Set: Impacts of Customized Chromatic Noise Models on Gravitational Wave Analyses

Nikita Agarwal, Gabriella Agazie, Alessandra Amosso +120

We report updated nHz gravitational wave (GW) significance, characterization, and interpretations using the customized chromatic-noise models (CNMs) developed in Larsen, Baier et a…

astro-ph.GA2026

Prospects of resolving and localising individual supermassive black hole binaries with pulsar timing arrays: the host ranking challenge

Niccolò Veronesi, Maria Charisi, Polina Petrov +5

Pulsar Timing Arrays (PTAs) are soon expected to detect individually resolved supermassive black hole (SMBH) binaries, opening the possibility for multi-messenger discoveries. The…

astro-ph.HE2026★ 1 cited

Searching for unresolved massive black hole pairs through AGN photometric variability

Lorenzo Bertassi, Maria Charisi, Fabio Rigamonti +2

Since their discovery, AGN light curves are known to be intrinsically variable. In the optical/UV band, this variability is consistent with correlated or red noise and is particula…

astro-ph.HE2026

Gravitational Wave Measurement of the - Intrinsic Scatter at High Redshift

Cayenne Matt, Kayhan Gültekin, Gabriella Agazie +109

The observed GWB spectrum is higher in amplitude than model predictions by a factor of 2-3. Using a semi-analytic model, we evaluate the effect of a high-scatter supermassive black…

astro-ph.HE2026

The NANOGrav 15 yr Data Set: Piecewise Power-Law Reconstruction of the Gravitational-Wave Background

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald +108

The NANOGrav 15-year (NG15) data set provides evidence for a gravitational-wave background (GWB) signal at nanohertz frequencies, which is expected to originate either from a cosmi…

astro-ph.GA2025

Identification of periodicities with arbitrary shapes in AGN light curves

Lorenzo Bertassi, Maria Charisi, Riccardo Buscicchio +3

Massive black hole binaries are expected to be observable as periodic AGN in time-domain photometric surveys. Periodicities may originate from different physical processes, includi…

astro-ph.GA2025

Multi-messenger Analysis of Supermassive Black Hole Binaries: The Joint-likelihood Approach

Maria Charisi, Stephen Taylor, Jessie Runnoe +2

Supermassive black hole binaries (SMBHBs) formed in galaxy mergers are promising multi-messenger sources. They can be identified as quasars with periodic variability in electromagn…

astro-ph.IM2025

Expectations for the first supermassive black-hole binary resolved by PTAs I: Model efficacy

Levi Schult, Polina Petrov, Stephen R. Taylor +4

One of the most promising targets for Pulsar Timing Arrays (PTAs) is identifying an individual supermassive black hole binary (SMBHB) out of the population of binaries theorized to…

astro-ph.IM2025★ 1 cited

Expectations for the first supermassive black-hole binary resolved by PTAs II: Milestones for binary characterization

Polina Petrov, Levi Schult, Stephen R. Taylor +4

Following the recent evidence for a gravitational wave (GW) background found by pulsar timing array (PTA) experiments, the next major science milestone is resolving individual supe…

astro-ph.HE2025

The Consequences of Rubin Observatory Time-Domain Survey Design and Host-Galaxy Contamination on the Identification of Binary Supermassive Black Holes

Megan C. Davis, Jonathan R. Trump, Maria Charisi +4

Binary supermassive black holes (SMBHs) are consequences of galaxy mergers and dominate the low-frequency gravitational wave background. Finding binary SMBHs in existing time-domai…

astro-ph.HE2025★ 4 cited

Inferring Mbh-Mbulge Evolution from the Gravitational Wave Background

Cayenne Matt, Kayhan Gultekin, Luke Kelley +104

We test the impact of an evolving supermassive black hole (SMBH) mass scaling relation (Mbh-Mbulge) on the predictions for the gravitational wave background (GWB). The observed GWB…

astro-ph.HE2025★ 11 cited

The NANOGrav 15 yr Data Set: Targeted Searches for Supermassive Black Hole Binaries

Nikita Agarwal, Gabriella Agazie, Akash Anumarlapudi +116

We present the first targeted searches for continuous gravitational waves (CWs) from 114 active galactic nuclei (AGN) that may host supermassive black hole binaries, using the NANO…

astro-ph.HE2025★ 1 cited

Lomb-Scargle periodograms struggle with non-sinusoidal supermassive BH binary signatures in quasar lightcurves

Allison Lin, Maria Charisi, Zoltan Haiman

Supermassive black hole binary (SMBHB) systems are expected to form as a consequence of galaxy mergers. At sub-parsec separations, SMBHBs can be identified as quasars with periodic…

astro-ph.HE2025★ 3 cited

The Host Galaxies of PTA Sources: Converting Supermassive BH Binary Parameters into EM Observables

Niccolo Veronesi, Maria Charisi, Stephen R Taylor +2

Pulsar timing arrays (PTAs) are approaching the sensitivity required to resolve gravitational waves (GWs) from individual supermassive black hole (SMBH) binaries. However, the larg…

astro-ph.GA2025

The Tantalizing Case of the Quasar J0950+5128 -- I. Presentation of the Data and Detailed Exploration of the Binary Supermassive Black Hole Scenario

Niana N. Mohammed, Jessie C. Runnoe, Michael Eracleous +8

Spectroscopic observations of the quasar J09505128 spanning 22 years reveal monotonic radial velocity variations in its broad H emission line. Moreover, the line profile beco…

gr-qc2025

The NANOGrav 15-year Data Set: Search for Gravitational Wave Memory

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald +102

We present the results of a search for nonlinear gravitational wave memory in the NANOGrav 15-year data set. We find no significant evidence for memory signals in the dataset, with…

astro-ph.HE2025★ 2 cited

Insights into Supermassive Black Hole Mergers from the Gravitational Wave Background

C. M. F. Mingarelli, L. Blecha, T. Bogdanović +9

At the Kavli Institute for Theoretical Physics, participants of the rapid response workshop on the gravitational wave background explored discrepancies between experimental results…

astro-ph.HE2024

The NANOGrav 15 yr Data Set: Harmonic Analysis of the Pulsar Angular Correlations

Gabriella Agazie, Jeremy G. Baier, Paul T. Baker +86

Pulsar timing array observations have found evidence for an isotropic gravitational wave background with the Hellings-Downs angular correlations, expected from general relativity.…

astro-ph.HE2024

The NANOGrav 15 Yr Data Set: Removing Pulsars One by One from the Pulsar Timing Array

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald +102

Evidence has emerged for a stochastic signal correlated among 67 pulsars within the 15-year pulsar-timing data set compiled by the NANOGrav collaboration. Similar signals have been…

astro-ph.HE2024★ 4 cited

Inference on inner galaxy structure via gravitational waves from supermassive binaries

Yifan Chen, Matthias Daniel, Daniel J. D'Orazio +107

The detection of a stochastic gravitational wave background by pulsar-timing arrays indicates the presence of a population of supermassive black hole binaries. Although the observe…

astro-ph.HE2024

The NANOGrav 15 yr Data Set: Running of the Spectral Index

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald +102

The NANOGrav 15-year data provides compelling evidence for a stochastic gravitational-wave (GW) background at nanohertz frequencies. The simplest model-independent approach to char…