학술논문

The NANOGrav 15-year Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries
Document Type
Working Paper
Author
Agazie, GabriellaAnumarlapudi, AkashArchibald, Anne M.Arzoumanian, ZavenBaker, Paul T.Bécsy, BenceBlecha, LauraBrazier, AdamBrook, Paul R.Burke-Spolaor, SarahCase, RobinCasey-Clyde, J. AndrewCharisi, MariaChatterjee, ShamiCohen, TylerCordes, James M.Cornish, NeilCrawford, FronefieldCromartie, H. ThankfulCrowter, KathrynDeCesar, MeganDemorest, Paul B.Digman, Matthew C.Dolch, TimothyDrachler, BrendanFerrara, Elizabeth C.Fiore, WilliamFonseca, EmmanuelFreedman, GabrielGarver-Daniels, NathanielGentile, PeterGlaser, JosephGood, DeborahGültekin, KayhanHazboun, JeffreyHourihane, SophieJennings, RossJohnson, Aaron D.Jones, MeganKaiser, Andrew R.Kaplan, DavidKelley, Luke ZoltanKerr, MatthewKey, JoeyLaal, NimaLam, MichaelLamb, William G.Lazio, T. Joseph W.Lewandowska, NataliaLiu, TingtingLorimer, Duncan R.Luo, Jing SantiagoLynch, Ryan S.Ma, Chung-PeiMadison, DustinMcEwen, AlexanderMcKee, James W.McLaughlin, MauraMcMann, NatashaMeyers, Bradley W.Meyers, Patrick M.Mingarelli, Chiara M. F.mitridate, andreanatarajan, priyaNg, CherryNice, DavidOcker, Stella KochOlum, KenPennucci, Timothy T.Perera, BenetgePetrov, PolinaPol, NihanRadovan, Henri A.Ransom, ScottRay, Paul S.Romano, JosephSardesai, Shashwat C.Schmiedekamp, AnnSchmiedekamp, CarlSchmitz, KaiShapiro-Albert, Brent J.Siemens, XavierSimon, JosephSiwek, MagdalenaStairs, IngridStinebring, DanStovall, KevinSusobhanan, AbhimanyuSwiggum, JosephTaylor, JacobTaylor, StephenTurner, Jacob E.Unal, CanerVallisneri, Michelevan Haasteren, RutgerVigeland, Sarah J.Wahl, Haley M.Witt, CaitlinYoung, Olivia
Source
Subject
Astrophysics - High Energy Astrophysical Phenomena
General Relativity and Quantum Cosmology
Language
Abstract
Evidence for a low-frequency stochastic gravitational wave background has recently been reported based on analyses of pulsar timing array data. The most likely source of such a background is a population of supermassive black hole binaries, the loudest of which may be individually detected in these datasets. Here we present the search for individual supermassive black hole binaries in the NANOGrav 15-year dataset. We introduce several new techniques, which enhance the efficiency and modeling accuracy of the analysis. The search uncovered weak evidence for two candidate signals, one with a gravitational-wave frequency of $\sim$4 nHz, and another at $\sim$170 nHz. The significance of the low-frequency candidate was greatly diminished when Hellings-Downs correlations were included in the background model. The high-frequency candidate was discounted due to the lack of a plausible host galaxy, the unlikely astrophysical prior odds of finding such a source, and since most of its support comes from a single pulsar with a commensurate binary period. Finding no compelling evidence for signals from individual binary systems, we place upper limits on the strain amplitude of gravitational waves emitted by such systems.
Comment: 23 pages, 13 figures, 2 tables. Accepted for publication in Astrophysical Journal Letters as part of Focus on NANOGrav's 15-year Data Set and the Gravitational Wave Background. For questions or comments, please email comments@nanograv.org