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The LIGO Scientific Collaboration, Virgo Collaboration,
J. Abadie,
B. P. Abbott,
R. Abbott,
T. D. Abbott,
M. Abernathy,
T. Accadia,
F. Acernese,
C. Adams, [......],
N. Zotov,
M. E. Zucker,
J. Zweizig,
M. S. Briggs,
V. Connaughton,
K. C. Hurley,
P. A. Jenke,
A. von Kienlin,
A. Rau,
X. -L. Zhang
[show abstract]
[hide abstract]
ABSTRACT: We present the results of a search for gravitational waves associated with
154 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray
experiments in 2009-2010, during the sixth LIGO science run and the second and
third Virgo science runs. We perform two distinct searches: a modeled search
for coalescences of either two neutron stars or a neutron star and black hole;
and a search for generic, unmodeled gravitational-wave bursts. We find no
evidence for gravitational-wave counterparts, either with any individual GRB in
this sample or with the population as a whole. For all GRBs we place lower
bounds on the distance to the progenitor, under the optimistic assumption of a
gravitational-wave emission energy of 10^-2 M c^2 at 150 Hz, with a median
limit of 17 Mpc. For short hard GRBs we place exclusion distances on binary
neutron star and neutron star-black hole progenitors, using astrophysically
motivated priors on the source parameters, with median values of 16 Mpc and 28
Mpc respectively. These distance limits, while significantly larger than for a
search that is not aided by GRB satellite observations, are not large enough to
expect a coincidence with a GRB. However, projecting these exclusions to the
sensitivities of Advanced LIGO and Virgo, which should begin operation in 2015,
we find that the detection of gravitational waves associated with GRBs will
become quite possible.
05/2012;
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LIGO Scientific Collaboration, Virgo Collaboration,
J. Abadie,
B. P. Abbott,
R. Abbott,
T. D. Abbott,
M. Abernathy,
T. Accadia,
F. Acernese,
C. Adams, [......],
R. Fender,
N. Gehrels,
A. Klotz,
E. O. Ofek,
M. Smith,
M. Sokolowski,
B. W. Stappers,
I. Steele,
J. Swinbank,
R. A. M. J. Wijeres
[show abstract]
[hide abstract]
ABSTRACT: Aims: A transient astrophysical event observed in both
gravitational wave (GW) and electromagnetic (EM) channels would yield
rich scientific rewards. A first program initiating EM follow-ups to
possible transient GW events has been developed and exercised by the
LIGO and Virgo community in association with several partners. In this
paper, we describe and evaluate the methods used to promptly identify
and localize GW event candidates and to request images of targeted sky
locations. Methods: During two observing periods (Dec. 17, 2009
to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis
pipeline was used to identify GW event candidates and to reconstruct
maps of possible sky locations. A catalog of nearby galaxies and Milky
Way globular clusters was used to select the most promising sky
positions to be imaged, and this directional information was delivered
to EM observatories with time lags of about thirty minutes. A Monte
Carlo simulation has been used to evaluate the low-latency GW pipeline's
ability to reconstruct source positions correctly. Results: For
signals near the detection threshold, our low-latency algorithms often
localized simulated GW burst signals to tens of square degrees, while
neutron star/neutron star inspirals and neutron star/black hole
inspirals were localized to a few hundred square degrees. Localization
precision improves for moderately stronger signals. The correct sky
location of signals well above threshold and originating from nearby
galaxies may be observed with ~50% or better probability with a few
pointings of wide-field telescopes.
Astronomy and Astrophysics 03/2012; 539:124. · 4.59 Impact Factor
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LIGO Scientific Collaboration, Virgo Collaboration,
J. Abadie,
B. P. Abbott,
R. Abbott,
T. D. Abbott,
M. Abernathy,
T. Accadia,
F. Acernese,
C. Adams, [......],
R. Fender,
N. Gehrels,
A. Klotz,
E. O. Ofek,
M. Smith,
M. Sokolowski,
B. W. Stappers,
I. Steele,
J. Swinbank,
R. A. M. J. Wijeres
[show abstract]
[hide abstract]
ABSTRACT: Aims: A transient astrophysical event observed in both
gravitational wave (GW) and electromagnetic (EM) channels would yield
rich scientific rewards. A first program initiating EM follow-ups to
possible transient GW events has been developed and exercised by the
LIGO and Virgo community in association with several partners. In this
paper, we describe and evaluate the methods used to promptly identify
and localize GW event candidates and to request images of targeted sky
locations. Methods: During two observing periods (Dec. 17, 2009
to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis
pipeline was used to identify GW event candidates and to reconstruct
maps of possible sky locations. A catalog of nearby galaxies and Milky
Way globular clusters was used to select the most promising sky
positions to be imaged, and this directional information was delivered
to EM observatories with time lags of about thirty minutes. A Monte
Carlo simulation has been used to evaluate the low-latency GW pipeline's
ability to reconstruct source positions correctly. Results: For
signals near the detection threshold, our low-latency algorithms often
localized simulated GW burst signals to tens of square degrees, while
neutron star/neutron star inspirals and neutron star/black hole
inspirals were localized to a few hundred square degrees. Localization
precision improves for moderately stronger signals. The correct sky
location of signals well above threshold and originating from nearby
galaxies may be observed with ~50% or better probability with a few
pointings of wide-field telescopes.
Astronomy and Astrophysics 03/2012; 539:124. · 4.59 Impact Factor
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The LIGO Scientific Collaboration, Virgo Collaboration,
J. Abadie,
B. P. Abbott,
R. Abbott,
T. D. Abbott,
M. Abernathy,
T. Accadia,
F. Acernese,
C. Adams, [......],
N. Gehrels,
A. Klotz,
E. O. Ofek,
M. Smith,
M. Sokolowski,
B. W. Stappers,
I. Steele,
J. Swinbank,
R. A. M. J. Wijers,
W. Zheng
[show abstract]
[hide abstract]
ABSTRACT: Aims. A transient astrophysical event observed in both gravitational wave
(GW) and electromagnetic (EM) channels would yield rich scientific rewards. A
first program initiating EM follow-ups to possible transient GW events has been
developed and exercised by the LIGO and Virgo community in association with
several partners. In this paper, we describe and evaluate the methods used to
promptly identify and localize GW event candidates and to request images of
targeted sky locations.
Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to
Oct 20 2010), a low-latency analysis pipeline was used to identify GW event
candidates and to reconstruct maps of possible sky locations. A catalog of
nearby galaxies and Milky Way globular clusters was used to select the most
promising sky positions to be imaged, and this directional information was
delivered to EM observatories with time lags of about thirty minutes. A Monte
Carlo simulation has been used to evaluate the low-latency GW pipeline's
ability to reconstruct source positions correctly.
Results. For signals near the detection threshold, our low-latency algorithms
often localized simulated GW burst signals to tens of square degrees, while
neutron star/neutron star inspirals and neutron star/black hole inspirals were
localized to a few hundred square degrees. Localization precision improves for
moderately stronger signals. The correct sky location of signals well above
threshold and originating from nearby galaxies may be observed with ~50% or
better probability with a few pointings of wide-field telescopes.
09/2011;
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LIGO Scientific Collaboration, Virgo Collaboration,
J. Abadie,
B. P. Abbott,
R. Abbott,
M Abernathy,
T. Accadia,
F. Acernese,
C. Adams,
R. Adhikari, [......],
P. P. Yu,
M. Yvert,
M. Zanolin,
L. Zhang,
Z. Zhang,
C. Zhao,
N. Zotov,
M. E. Zucker,
J. Zweizig,
K. Belczynski
[show abstract]
[hide abstract]
ABSTRACT: We present an up-to-date, comprehensive summary of the rates for all types of
compact binary coalescence sources detectable by the Initial and Advanced
versions of the ground-based gravitational-wave detectors LIGO and Virgo.
Astrophysical estimates for compact-binary coalescence rates depend on a number
of assumptions and unknown model parameters, and are still uncertain. The most
confident among these estimates are the rate predictions for coalescing binary
neutron stars which are based on extrapolations from observed binary pulsars in
our Galaxy. These yield a likely coalescence rate of 100 per Myr per Milky Way
Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 per
Myr per MWEG to 1000 per Myr per MWEG. We convert coalescence rates into
detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and
projected sensitivities for our Advanced detectors. Using the detector
sensitivities derived from these data, we find a likely detection rate of 0.02
per year for Initial LIGO-Virgo interferometers, with a plausible range between
0.0002 and 0.2 per year. The likely binary neutron-star detection rate for the
Advanced LIGO-Virgo network increases to 40 events per year, with a range
between 0.4 and 400 per year.
03/2010;
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LIGO Scientific Collaboration, Virgo Collaboration,
B. P. Abbott,
R. Abbott,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen,
G. Allen,
M. Alshourbagy, [......],
Z. Yan,
S. Yoshida,
M. Yvert,
M. Zanolin,
J. Zhang,
L. Zhang,
C. Zhao,
N. Zotov,
M. E. Zucker,
J. Zweizig
[show abstract]
[hide abstract]
ABSTRACT: We present the results of a search for gravitational-wave bursts associated
with 137 gamma-ray bursts (GRBs) that were detected by satellite-based
gamma-ray experiments during the fifth LIGO science run and first Virgo science
run. The data used in this analysis were collected from 2005 November 4 to 2007
October 1, and most of the GRB triggers were from the Swift satellite. The
search uses a coherent network analysis method that takes into account the
different locations and orientations of the interferometers at the three
LIGO-Virgo sites. We find no evidence for gravitational-wave burst signals
associated with this sample of GRBs. Using simulated short-duration (<1 s)
waveforms, we set upper limits on the amplitude of gravitational waves
associated with each GRB. We also place lower bounds on the distance to each
GRB under the assumption of a fixed energy emission in gravitational waves,
with typical limits of D ~ 15 Mpc (E_GW^iso / 0.01 M_o c^2)^1/2 for emission at
frequencies around 150 Hz, where the LIGO-Virgo detector network has best
sensitivity. We present astrophysical interpretations and implications of these
results, and prospects for corresponding searches during future LIGO-Virgo
runs.
The Astrophysical Journal 08/2009; · 6.02 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: In gravitational-wave detection, special emphasis is put onto searches that
focus on cosmic events detected by other types of astrophysical observatories.
The astrophysical triggers, e.g. from gamma-ray and X-ray satellites, optical
telescopes and neutrino observatories, provide a trigger time for analyzing
gravitational wave data coincident with the event. In certain cases the
expected frequency range, source energetics, directional and progenitor
information is also available. Beyond allowing the recognition of gravitational
waveforms with amplitudes closer to the noise floor of the detector, these
triggered searches should also lead to rich science results even before the
onset of Advanced LIGO. In this paper we provide a broad review of LIGO's
astrophysically triggered searches and the sources they target.
03/2008;
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[show abstract]
[hide abstract]
ABSTRACT: We present a method to search for transient GWs using a network of detectors
with different spectral and directional sensitivities: the interferometer Virgo
and the bar detector AURIGA. The data analysis method is based on the
measurements of the correlated energy in the network by means of a weighted
cross-correlation. To limit the computational load, this coherent analysis step
is performed around time-frequency coincident triggers selected by an excess
power event trigger generator tuned at low thresholds. The final selection of
GW candidates is performed by a combined cut on the correlated energy and on
the significance as measured by the event trigger generator. The method has
been tested on one day of data of AURIGA and Virgo during September 2005. The
outcomes are compared to the results of a stand-alone time-frequency
coincidence search. We discuss the advantages and the limits of this approach,
in view of a possible future joint search between AURIGA and one
interferometric detector.
02/2008;
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[show abstract]
[hide abstract]
ABSTRACT: The VIRGO suspensions are chains of passive mechanical filters designed
to isolate the interferometer mirrors from seismic noise starting from a
few Hz. In order to reduce the low-frequency swing of the mirror along
the beam, an active control system, acting at the level of the
suspension point, damps the main resonant modes of the system (all below
2.5 Hz). Another control loop, at the level of the optical payload,
makes use of a digital camera monitoring the mirror position in all six
degrees of freedom. Its main goal is to decrease the rms angular
displacements of the mirror, on a time scale of several minutes, down to
less than 1 μrad. All the seven suspensions of the VIRGO central
interferometer are presently in operation, while the assembly of the
last two, for the terminal mirrors, is in progress. The design and
performance of the system are described in this paper.
Classical and Quantum Gravity 03/2002; 19:1623-1629. · 3.32 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The status of the VIRGO experiment, as of summer 2000 is presented: we
report on the progress in the construction and the next steps are
briefly illustrated. .
01/2001; 555:138-145.
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-1:86.
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B. P. Abbott,
R Abbott,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen,
G Allen,
M. Alshourbagy,
R. S. Amin,
S. B. Anderson, [......],
M Yvert,
M. Zanolin,
J Zhang,
L Zhang,
C Zhao,
N. Zotov,
M. E. Zucker,
J. Zweizig,
LIGO Sci Collaboration, VIRGO Collaboration
[show abstract]
[hide abstract]
ABSTRACT: A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations(1). Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory(2) (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 X 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter(3), as well as cosmic (super) string models with relatively small string tension(4) that are favoured in some string theory models(5). This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis(1,6) and cosmic microwave background(7) at 100Hz.
Nature, v.460, 990-994 (2009).
-
BP Abbott,
R Abbott,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen,
G Allen,
M. Alshourbagy,
RS Amin,
SB Anderson, [......],
AG Lyne,
RN Manchester,
FE Marshall,
J. Middleditch,
A. Possenti,
SM Ransom,
IH Stairs,
B. Stappers,
LIGO Sci Collaboration, VIRGO Collaboration
-
LIGO Sci Collaboration, VIRGO Collaboration,
BP Abbott,
R Abbott,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen,
G Allen,
M. Alshourbagy, [......],
S Yoshida,
M Yvert,
M. Zanolin,
J Zhang,
L Zhang,
C Zhao,
N. Zotov,
ME Zucker,
H zur Muehlen,
J. Zweizig
-
LIGO Sci Collaboration, VIRGO Collaboration,
J. Abadie,
BP Abbott,
R Abbott,
T. Accadia,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen, [......],
S Yoshida,
PP Yu,
M Yvert,
M. Zanolin,
L Zhang,
Z Zhang,
C Zhao,
N. Zotov,
ME Zucker,
J. Zweizig
-
LIGO Sci Collaboration, VIRGO Collaboration,
J. Abadie,
BP Abbott,
R Abbott,
T. Accadia,
F. Acernese,
R. Adhikari,
P. Ajith,
B. Allen, [......],
D. Yeaton-Massey,
S Yoshida,
M Yvert,
M. Zanolin,
L Zhang,
Z Zhang,
C Zhao,
N. Zotov,
ME Zucker,
J. Zweizig
-
LIGO Sci Collaboration, VIRGO Collaboration,
J. Abadie,
BP Abbott,
R Abbott,
M. Abernathy,
T. Accadia,
F. Acerneseac,
C Adams,
R. Adhikari, [......],
M Yvert,
M. Zanolin,
L Zhang,
Z Zhang,
C Zhao,
N. Zotov,
ME Zucker,
J. Zweizig,
K. Belczynski,
LIGO Sci Collaboration \& Virgo
