| | |
| | |
Stat |
Members: 3643 Articles: 2'487'895 Articles rated: 2609
29 March 2024 |
|
| | | |
|
Article overview
| |
|
European Pulsar Timing Array Limits On An Isotropic Stochastic Gravitational-Wave Background | Lindley Lentati
; Stephen R. Taylor
; Chiara M. F. Mingarelli
; Alberto Sesana
; Sotiris A. Sanidas
; Alberto Vecchio
; R. Nicolas Caballero
; K. J. Lee
; Rutger van Haasteren
; Stanislav Babak
; Cees G. Bassa
; Patrick Brem
; Marta Burgay
; David J. Champion
; Ismael Cognard
; Gregory Desvignes
; Jonathon R. Gair
; Lucas Guillemot
; Jason W. T. Hessels
; Gemma H. Janssen
; Ramesh Karuppusamy
; Michael Kramer
; Antoine Lassus
; Patrick Lazarus
; Kuo Liu
; Stefan Osłowski
; Delphine Perrodin
; Antoine Petiteau
; Andrea Possenti
; Mark B. Purver
; Pablo A. Rosado
; Roy Smits
; Ben Stappers
; Gilles Theureau
; Caterina Tiburzi
; Joris P. W. Verbiest
; | Date: |
14 Apr 2015 | Abstract: | We present new limits on an isotropic stochastic gravitational-wave
background (GWB) using a six pulsar dataset spanning 18 yr of observations from
the 2015 European Pulsar Timing Array data release (Desvignes et al. in prep.).
Performing a Bayesian analysis, we fit simultaneously for the intrinsic noise
parameters for each pulsar in this dataset, along with common correlated
signals including clock, and Solar System ephemeris errors to obtain a robust
95$\%$ upper limit on the dimensionless strain amplitude $A$ of the background
of $A<3.0 imes 10^{-15}$ at a reference frequency of $1mathrm{yr^{-1}}$ and a
spectral index of $13/3$, corresponding to a background from inspiralling
super-massive black hole binaries, constraining the GW energy density to
$Omega_mathrm{gw}(f)h^2 < 3.6 imes10^{-10}$ at 2.8 nHz. We show that
performing such an analysis when fixing the intrinsic noise parameters for the
individual pulsars leads to an erroneously stringent upper limit, by a factor
$sim 1.7$. We obtain a difference in the logarithm of the Bayesian evidence
between models that include either a correlated background, or uncorrelated
common red noise of $-1.0 pm 0.5$, indicating no support for the presence of a
correlated GWB in this dataset. We discuss the implications of our analysis for
the astrophysics of supermassive black hole binaries, and present 95$\%$ upper
limits on the string tension, $Gmu/c^2$, characterising a background produced
by a cosmic string network for a set of possible scenarios, and for a
stochastic relic GWB. For a Nambu-Goto field theory cosmic string network, we
set a limit $Gmu/c^2<1.3 imes10^{-7}$, identical to that set by the Planck
Collaboration, combining Planck and high-$ell$ Cosmic Microwave Background
data from other experiments. (Abridged) | Source: | arXiv, 1504.3692 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser claudebot
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |