122 research outputs found
Methods and results of a search for gravitational waves associated with gamma-ray bursts using the GEO 600, LIGO, and Virgo detectors
Paper producido por "The LIGO Scientific Collaboration and the Virgo Collaboration". (En el registro se mencionan solo algunos autores de las decenas de personas que participan).In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz–1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. We introduce the method of a linear search grid to analyze GRB events with large sky localization uncertainties, for example the localizations provided by the Fermi Gamma-ray Burst Monitor (GBM). Coherent searches for gravitational waves (GWs) can be computationally intensive when the GRB sky position is not well localized, due to the corrections required for the difference in arrival time between
detectors. Using a linear search grid we are able to reduce the computational cost of the analysis by a factor of Oð10Þfor GBM events. Furthermore, we demonstrate that our analysis pipeline can improve upon the sky localization of GRBs detected by the GBM, if a high-frequency GW signal is observed in coincidence. We use the method of the linear grid in a search for GWs associated with 129 GRBs observed satellite-based gamma-ray experiments between 2006 and 2011. The GRBs in our sample had not been previously analyzed for GW counterparts. A fraction of our GRB events are analyzed using data from GEO 600 while
the detector was using squeezed-light states to improve its sensitivity; this is the first search for GWs using data from a squeezed-light interferometric observatory. We find no evidence for GW signals, either with any individual GRB in this sample or with the population as a whole. For each GRB we place lower bounds on the distance to the progenitor, under an assumption of a fixed GWemission energy of 10−2M⊙c2, with a median exclusion distance of 0.8 Mpc for emission at 500 Hz and 0.3 Mpc at 1 kHz. The reduced computational cost associated with a linear search grid will enable rapid searches for GWs associated with
Fermi GBM events once the advanced LIGO and Virgo detectors begin operation.http://journals.aps.org/prd/abstract/10.1103/PhysRevD.89.122004publishedVersionFil: Aasi, J. LIGO. California Institute of Technology; Estados Unidos de América.Fil: Domínguez, E. Argentinian Gravitational Wave Group; Argentina.Fil: Maglione, C. Argentinian Gravitational Wave Group; Argentina.Fil: Reula, O. Argentinian Gravitational Wave Group; Argentina.Fil: Ortega, W. Argentinian Gravitational Wave Group; Argentina.Fil: Wolovick, N. Argentinian Gravitational Wave Group; Argentina.Fil: Schilman, M. Argentinian Gravitational Wave Group; Argentina.Física de Partículas y Campo
Search of the Orion spur for continuous gravitational waves using a loosely coherent algorithm on data from LIGO interferometers
We report results of a wideband search for periodic gravitational waves from isolated neutron stars within the Orion spur towards both the inner and outer regions of our Galaxy. As gravitational waves interact very weakly with matter, the search is unimpeded by dust and concentrations of stars. One search disk (A) is 6.87° in diameter and centered on 20h10m54.71s+33°33′25.29′′, and the other (B) is 7.45° in diameter and centered on 8h35m20.61s-46°49′25.151′′. We explored the frequency range of 50-1500 Hz and frequency derivative from 0 to -5×10-9 Hz/s. A multistage, loosely coherent search program allowed probing more deeply than before in these two regions, while increasing coherence length with every stage. Rigorous follow-up parameters have winnowed the initial coincidence set to only 70 candidates, to be examined manually. None of those 70 candidates proved to be consistent with an isolated gravitational-wave emitter, and 95% confidence level upper limits were placed on continuous-wave strain amplitudes. Near 169 Hz we achieve our lowest 95% C.L. upper limit on the worst-case linearly polarized strain amplitude h0 of 6.3×10-25, while at the high end of our frequency range we achieve a worst-case upper limit of 3.4×10-24 for all polarizations and sky locations. © 2016 American Physical Society
A search of the Orion spur for continuous gravitational waves using a "loosely coherent" algorithm on data from LIGO interferometers
We report results of a wideband search for periodic gravitational waves from
isolated neutron stars within the Orion spur towards both the inner and outer
regions of our Galaxy. As gravitational waves interact very weakly with matter,
the search is unimpeded by dust and concentrations of stars. One search disk
(A) is in diameter and centered on
, and the other
(B) is in diameter and centered on
. We explored the
frequency range of 50-1500 Hz and frequency derivative from to Hz/s. A multi-stage, loosely coherent search program allowed probing
more deeply than before in these two regions, while increasing coherence length
with every stage.
Rigorous followup parameters have winnowed initial coincidence set to only 70
candidates, to be examined manually. None of those 70 candidates proved to be
consistent with an isolated gravitational wave emitter, and 95% confidence
level upper limits were placed on continuous-wave strain amplitudes. Near
Hz we achieve our lowest 95% CL upper limit on worst-case linearly polarized
strain amplitude of , while at the high end of our
frequency range we achieve a worst-case upper limit of for
all polarizations and sky locations.Comment: Fixed minor typo - duplicate name in the author lis
Effects of Data Quality Vetoes on a Search for Compact Binary Coalescences in Advanced LIGO's First Observing Run
The first observing run of Advanced LIGO spanned 4 months, from September 12,
2015 to January 19, 2016, during which gravitational waves were directly
detected from two binary black hole systems, namely GW150914 and GW151226.
Confident detection of gravitational waves requires an understanding of
instrumental transients and artifacts that can reduce the sensitivity of a
search. Studies of the quality of the detector data yield insights into the
cause of instrumental artifacts and data quality vetoes specific to a search
are produced to mitigate the effects of problematic data. In this paper, the
systematic removal of noisy data from analysis time is shown to improve the
sensitivity of searches for compact binary coalescences. The output of the
PyCBC pipeline, which is a python-based code package used to search for
gravitational wave signals from compact binary coalescences, is used as a
metric for improvement. GW150914 was a loud enough signal that removing noisy
data did not improve its significance. However, the removal of data with excess
noise decreased the false alarm rate of GW151226 by more than two orders of
magnitude, from 1 in 770 years to less than 1 in 186000 years.Comment: 27 pages, 13 figures, published versio
Searches for continuous gravitational waves from nine young supernova remnants
We describe directed searches for continuous gravitational waves in data from
the sixth LIGO science data run. The targets were nine young supernova remnants
not associated with pulsars; eight of the remnants are associated with
non-pulsing suspected neutron stars. One target's parameters are uncertain
enough to warrant two searches, for a total of ten. Each search covered a broad
band of frequencies and first and second frequency derivatives for a fixed sky
direction. The searches coherently integrated data from the two LIGO
interferometers over time spans from 5.3-25.3 days using the matched-filtering
F-statistic. We found no credible gravitational-wave signals. We set 95%
confidence upper limits as strong (low) as on intrinsic
strain, on fiducial ellipticity, and on
r-mode amplitude. These beat the indirect limits from energy conservation and
are within the range of theoretical predictions for neutron-star ellipticities
and r-mode amplitudes.Comment: Science summary available at
http://www.ligo.org/science/Publication-S6DirectedSNR/index.ph
Supplement: "Localization and broadband follow-up of the gravitational-wave transient GW150914" (2016, ApJL, 826, L13)
This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands
All-sky search for long-duration gravitational wave transients with initial LIGO
We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10–500 s in a frequency band of 40–1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10−5 and 9.4×10−4 Mpc−3 yr−1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves
All-sky search for long-duration gravitational wave transients with initial LIGO
We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society
All-sky search for long-duration gravitational wave transients with initial LIGO
We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society
Multimessenger Search for Sources of Gravitational Waves and High-Energy Neutrinos: Results for Initial LIGO-Virgo and IceCube
We report the results of a multimessenger search for coincident signals from
the LIGO and Virgo gravitational-wave observatories and the partially completed
IceCube high-energy neutrino detector, including periods of joint operation
between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010
run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79
strings. We find no significant coincident events, and use the search results
to derive upper limits on the rate of joint sources for a range of source
emission parameters. For the optimistic assumption of gravitational-wave
emission energy of \,Mc at \,Hz with \,ms duration, and high-energy neutrino emission of \,erg
comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the
source rate below \,Mpcyr. We also examine
how combining information from gravitational waves and neutrinos will aid
discovery in the advanced gravitational-wave detector era
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