| Literature DB >> 26252674 |
S R Taylor1,2, C M F Mingarelli3,4,5, J R Gair2, A Sesana5,6, G Theureau7,8,9, S Babak6, C G Bassa10,11, P Brem6, M Burgay12, R N Caballero4, D J Champion4, I Cognard7,8, G Desvignes4, L Guillemot7,8, J W T Hessels10,13, G H Janssen10,11, R Karuppusamy4, M Kramer4,11, A Lassus4,7, P Lazarus4, L Lentati14, K Liu4, S Osłowski4,15, D Perrodin12, A Petiteau16, A Possenti12, M B Purver11, P A Rosado17,18, S A Sanidas11,13, R Smits10, B Stappers11, C Tiburzi12,19, R van Haasteren1, A Vecchio5, J P W Verbiest4,15.
Abstract
The paucity of observed supermassive black hole binaries (SMBHBs) may imply that the gravitational wave background (GWB) from this population is anisotropic, rendering existing analyses suboptimal. We present the first constraints on the angular distribution of a nanohertz stochastic GWB from circular, inspiral-driven SMBHBs using the 2015 European Pulsar Timing Array data. Our analysis of the GWB in the ~2-90 nHz band shows consistency with isotropy, with the strain amplitude in l>0 spherical harmonic multipoles ≲40% of the monopole value. We expect that these more general techniques will become standard tools to probe the angular distribution of source populations.Entities:
Year: 2015 PMID： 26252674 DOI： 10.1103/PhysRevLett.115.041101
Source DB: PubMed Journal: Phys Rev Lett ISSN： 0031-9007 Impact factor: 9.161