124 citations · 660 across the 50 of their papers we have counts for
53 papers
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…
The October 2022 flare in OJ 287 and the mass of its primary black hole
Mauri J. Valtonen, Staszek Zola, Manpreet Singh +21
The bright blazar OJ~287 has demonstrated a sequence of flares, which are well explained by a quasi-Keplerian orbit model. The flares are associated with the impact of the secondar…
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…
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…
Mitigating the Timing Impact of Anomalous Pulse Profile Shape Variability in PSR J1713+0747 with Gaussian Component Modeling
Shania A. Nichols, Michael T. Lam, Gabriella Agazie +31
The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) achieves sub-microsecond timing precision for several millisecond pulsars in its pulsar timing array (PT…
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…
The NANOGrav 15 yr and 20 yr Datasets: Timing Events and Pulse Shape Changes
Ben Jacobson-Bell, James M. Cordes, Shami Chatterjee +61
The average pulse shape of a pulsar is typically stable over decadal timescales, enabling estimation of pulse times of arrival to better than a small fraction of the pulse width us…
The GMRT High-Resolution Southern Sky Survey for pulsars and transients -- VIII: Orbital Variability and the Evolution of a 1-Day He-WD Millisecond Pulsar J2101-4802
Ankita Ghosh, Bhaswati Bhattacharyya, David L. Kaplan +8
We present timing and orbital phase-resolved polarimetry of the millisecond pulsar (MSP) J21014802, having a spin period of 9.48~ms and dispersion measure (DM) $25.05\ \mathrm{p…
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…
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…
Identifying the secondary jet in the RadioAstron image of OJ~287
Mauri J. Valtonen, Lankeswar Dey, Staszek Zola +26
The 136 year long optical light curve of OJ~287 is explained by a binary black hole model where the secondary is in a 12 year orbit around the primary. Impacts of the secondary on…
Searching for Exotrojans in Pulsar Systems
Jackson D. Taylor, Emmanuel Fonseca, Lankeswar Dey +50
Trojan asteroids are found in the equilateral triangle Lagrange points of the Sun-Jupiter system in great number, though they also exist less prolifically in other parts of the Sol…
Revealing a ribbon-like jet in OJ 287 with RadioAstron
E. Traianou, J. L. Gomez, I. Cho +17
We present space-based very long baseline interferometry observations of the BL Lac type object OJ 287 taken with RadioAstron at 22 GHz on April 25, 2016, in conjunction with a gro…
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…
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…
The NANOGrav 15-year Data Set: Search for Gravitational Scattering of Pulsars by Free-Floating Objects in Interstellar Space
Lankeswar Dey, Ross J. Jennings, Jackson D. Taylor +48
Free-floating objects (FFOs) in interstellar spacerogue planets, brown dwarfs, and large asteroids that are not gravitationally bound to any starare expected to be ubiquitous…
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…
Pulse Profile Variability of PSR J1022+1001 in NANOGrav Data
William Fiore, Maura A. McLaughlin, Gabriella Agazie +46
Pulse profile stability is a central assumption of standard pulsar timing methods. Thus, it is important for pulsar timing array experiments such as the North American Nanohertz Ob…
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.…
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…
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…
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…
The NANOGrav 15 yr data set: Posterior predictive checks for gravitational-wave detection with pulsar timing arrays
Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald +99
Pulsar-timing-array experiments have reported evidence for a stochastic background of nanohertz gravitational waves consistent with the signal expected from a population of superma…
Exploring pulsar timing precision: A comparative study of polarization calibration methods for NANOGrav data from the Green Bank Telescope
Lankeswar Dey, Maura A. McLaughlin, Haley M. Wahl +32
Pulsar timing array experiments have recently uncovered evidence for a nanohertz gravitational wave background by precisely timing an ensemble of millisecond pulsars. The next sign…